Sonntag, 9. Juli 2017 - 21:00 Uhr

Raumfahrt - In eine russische Militärbasis einzubrechen, um eine verlassene sowjetische Raumfähre zu sehen, war das Risiko wert


Breaking Into a Russian Military Base to See an Abandoned Soviet Space Shuttle Was Worth the Risk


Because any trip to see a Soviet shuttle is worth it as long as no one’s wearing handcuffs at the end.

A group of YouTubers going by the name Exploring the Unbeaten Path traveled to the middle of nowhere to get a look at some space shuttles from the suspended Soviet-era Buran programme. Located at the Baikonur Cosmodromespaceport in Kazakhstan, the hanger that the group would have to infiltrate is abandoned but the base is still active.


The world’s first and largest space launch facility, Baikonur is leased by the Russian government and all crewed Russian missions still launch from there. Commercial and military missions are also staged at the spaceport, and soldiers patrol the area.

Although the explorers have numerous scares, they manage to get into the facility and spend a lot of time. They brought back tons of footage of the shuttles on the inside and out, even managing to fly a drone through the enormous hanger. 


Tags: UdSSR Buran Shuttle Raumfahrt - In eine russische Militärbasis einzubrechen, um eine verlassene sowjetische Raumfähre zu sehen, war das Risiko wert 


Sonntag, 9. Juli 2017 - 19:00 Uhr

Raumfahrt - Merkur Mission BepiColombo 2017 - Update-2


Flight into the furnace of Mercury could bring us closer in hunt for alien life

An artist’s impression of the BepiColombo.
 An artist’s impression of the BepiColombo’s planetary orbiter and magnetospheric orbiter above Mercury. Photograph: ESA

The crucial point, McCaughrean said, is that scientists cannot be sure just how habitable an exoplanet is until they understand conditions on a world that orbits near a star. Hence the importance of Mercury. However, the little world – the most cratered planet in the solar system – offers other important goals for science.


Another mystery that astronomers hope to solve is the puzzle of Mercury’s magnetic field. It is the only rocky planet in our solar system, other than Earth, that has one, though it is about 100 times weaker than ours. However, studies by the US probe Messenger – which orbited Mercury between 2011 and 2015 – discovered that this field is offset from the planet’s centre by about 500 kilometres, an astonishing amount for a little planet.

“In fact, most theories about the formation of our solar system suggest that a tiny world like Mercury should not have a magnetic field at all, so we are facing a real mystery,” said McCaughrean. “We cannot claim we understand how our solar system formed if we cannot explain why Mercury possesses such an anomaly. We have real theoretical issues to resolve, and hopefully BepiColombo will let us do that.”

In addition, BepiColombo will seek out regions, in high latitudes, where its predecessor Messenger found evidence of water ice inside the unlit walls of craters. Their existence is another of the puzzles that astronomers have uncovered on this little planet.

Designing and building a craft that can achieve these goals has not been easy. BepiColombo – named after the 20th-century Italian mathematician and engineer Giuseppe Colombo – is actually a twin spacecraft: a European planetary orbiter that will study the planet and a Japanese craft that will study the planet’s magnetic field. Both will be carried to their target by a propulsion module known as the Mercury transfer module.

The mission was approved in 2000 by the European Space Agency in collaboration with Jaxa. However, the complexities of flying a probe so close to the Sun forced design delays that raised costs from several hundred million euros to the probe’s current estimated price tag of about €1.6bn. It also triggered years of delay in building the satellite. Indeed, the project came close to termination when several member states, including Britain, urged that no extra funds be made available after costs over-ran to several hundred million euros. It took weeks of complex negotiations to save the project.


The main problem facing BepiColombo was that the mission’s principal orbiter has to be flown so that it hovers over the searing hot surface of Mercury while the Sun beams down on it. “Solar radiation is 10 times the level on Mercury than it is on Earth because the planet is so close to the Sun,” said Mauro Patroncini, of Thales Alenia Space Italia, which built much of the probe. “At the same time, Mercury’s surface is so hot – about 430C – that it generates a massive flux of infrared radiation and heat of its own.” Essentially the satellite will be grilled on both sides: the Sun on one and Mercury on the other.

“We thought we could deal with that with conventional techniques when we were designing the craft, but realised in 2006 that we would have to develop new technologies, including temperature-resistant coatings and insulated instruments, to stop the craft overheating violently,” said Patroncini. “That is what caused the delays and cost over-runs.”

The danger of overheating was endorsed by ESA project manager Ulrich Reininghaus, who also stressed the problems that lay ahead for the mission. “We’re flying into a pizza oven. We had to test materials at different, very high temperature regimes, sometimes with very unwanted results.” Hence the delays in launch.

Constructing a craft that can endure such hellish conditions has proven to be a gruelling business. There were tears of frustration over the delays, and a great deal of sweat was expended in redesigning a craft that has pushed engineers to the limit of their abilities, said McCaughrean. Then there was the construction race after all the delays.

“BepiColombo has sheets of tough insulating material that has had to be sown, by hand, into position in its sun shield and other parts,” he said. “A colleague went into the probe’s assembly area one morning and found blood spattered beside it. Another member of staff had stabbed themselves with a needle overnight as they stitched up the thermal blankets. So you could easily say that blood, sweat and tears were expended in getting this mission ready for launch.”


BepiColombo is a probe of many parts: a massive sunshade, a planetary orbiter, a second orbiter that will study the planet’s magnetic field, and a transfer vehicle that will carry these various components to Mercury after the mission’s launch on an Ariane 5 rocket from Europe’s spaceport in Kourou, French Guiana, in October 2018.


The craft will weigh more than 4 tonnes, including 1.4 tonnes of propellant that will be used to power it on a complex journey round the solar system en route to Mercury. The trip will take seven years and will involve making one flyby of Earth, two of Venus and six of Mercury in order to position the craft when it reaches its destination in 2025 in a way that makes it easy to slip into orbit around the planet.

“We could fire BepiColombo straight at Mercury and it would get there in a few months, but we would have to use all our fuel decelerating to reach the planet at a reasonable speed,” said Mark McCaughrean, the ESA’s senior scientific adviser. “That is why we are taking the slow way.”

Once in orbit round Mercury, the transfer vehicle will release its two orbiters. The European craft will map Mercury while the Japanese craft will hover further from the planet and study its magnetic field. BepiColombo is designed to operate for one year, but with the option of running for a second. Privately ESA officials hope they will get up to three or four years out of the craft.

Quelle: theguardian

Tags: Raumfahrt - Merkur Mission BepiColombo 2017 - Update-2 


Samstag, 8. Juli 2017 - 20:30 Uhr

Astronomie - Radioteleskop (Square Kilometre Array) SKA) in Südafrika-Update-2



Giant SKA telescope rattles South African community

Struggle in Northern Cape province highlights a balancing act that scientists leading gigantic projects face.

The MeerKAT telescope under construction in South Africa’s Northern Cape will form part of the world’s largest radio telescope.
“Move it away! We don’t want it!” a farmer shouted at a crowded meeting in Carnarvon, a small town in the semi-arid, sparsely populated Northern Cape, one of South Africa’s poorer provinces. He was talking about what will be the largest radio telescope in the world, the international Square Kilometre Array (SKA), a portion of which is due to be built nearby.
Representatives from SKA South Africa, an organization of scientists, engineers and technocrats, were attending the meeting of farmers in May, in an attempt to respond to rising criticism of the project from local people. “It’s fine to be part of the international community, but how is it helping this community?” came a faceless call from the other side of the meeting hall.
In 2012, the SKA’s coordinating organization decided that it would divide its thousands of dishes and many more antennas, whose combined ‘collecting area’ for radio waves will span approximately one square kilometre, between Australia and South Africa. The site in the Northern Cape will include 197 dishes, and form part of the project’s first phase, SKA1. The 64-dish MeerKAT tele­scope, which will be part of SKA1, is already being built. The rest of the dishes will be added from 2018.
Last year, opposition to the Thirty Meter Tele­scope on Mauna Kea, Hawaii, prompted the state’s supreme court to invalidate the telescope’s construction permit. Opposition to the SKA is unlikely to derail the project because legislation protects most of the Northern Cape for astronomy. But SKA South Africa officials say that they need community buy-in if the project is to be sustainable over its 50-year life.
The struggle that is playing out in the Northern Cape illustrates the balancing act that scientists who lead gigantic projects must pull off — to highlight the benefits that the project will bring to an area without over­inflating expectations.
When SKA South Africa proposed the SKA project to the Northern Cape community, starting with the MeerKAT telescope in 2008, it said that the project would lead to local economic development, create jobs and improve opportunities for children through education and science. But the organization never quantified these objectives — and now its director, Rob Adam, is struggling to manage the expectations of the poorest members of the Northern Cape, who are largely ‘coloured’ people, a recognized racial classification in South Africa.
SKA South Africa has already come good on some of its promises. It now employs a high-school maths and science teacher for Carnarvon, for example, and is paying for five coloured students at Carnarvon high school to attend university as part of a pan-African bursary programme that it runs. But members of the coloured community complain that such resources haven’t materialized across the board — not all the towns in the area have gained a high-school teacher, for example.
And although a small influx of scientists, engineers and contractors has to some extent improved the economies of the province’s towns, the communities are not yet satisfied. “What’s in it for us?” asked one resident at a meeting in the Northern Cape town of Brandvlei in May.
Adam says that the community’s expectations have risen beyond what the SKA can provide. “You must understand, we are not the government, the education department and the police, all rolled into one,” he told the crowd in Brandvlei.
The problem is different for members of the richer, mainly white, sheep-farming community of the Northern Cape, who are concerned about SKA South Africa’s land acquisition.
According to the Astronomy Geographic Advantage Act, which was passed in 2007, the government has the right to acquire land for the project within a designated ‘core’ area if negotiations fail, and if the land is required for the SKA and the organization has offered a fair price.
Northern Cape residents voice discontent with construction of the Square Kilometre Array.
In 2008, the government bought Losberg farm, the site of the MeerKAT telescope. What is riling this community is that SKA South Africa is now eyeing 36 other farms — which comprise about 118,000 hectares — to accommodate the further 133 dishes that make up SKA1.
Many farmers say that the loss of their farms will destroy the local, agriculture-based economy, and that they are being forced to sell. Although the amount of land needed for the SKA is now agreed, the farmers are also suspicious about the scope of the project. “They don’t believe things will stop here,” says Henning Myburgh, general manager of farmers’ organization Agri Northern Cape in Kimberley.
The spectre of Zimbabwe-style land expropriation, in which the government took land from white farmers without compensation, is also present. “It’s a land grab, one way or the other, be it for SKA or something else,” says Eric Torr, a former resident of the province who owns a local aviation company.
Expropriation would be a last resort, say SKA South Africa officials. “It’s not in the best interests of the SKA to do that because we have to live in this community,” says Alice Pienaar-Marais, who is in charge of the land-acquisition process. She is confident that SKA South Africa will acquire the 36 farms by the end of next year, in time for SKA1 construction in 2018.
SKA Australia, meanwhile, “could be doing more” with respect to community engagement, project director David Luchetti told Nature.
The Australian SKA Pathfinder telescope, which is currently being commissioned, is to be built on an area that traditionally belongs to the Wajarri Yamatji tribe. Following the 2009 Indigenous Land Use Agreement, which was negotiated between the government and the indigenous group, the tribe has received benefits worth more than Aus$18.1 million (US$13.5 million) in exchange for the use of the land for radio­astronomy.
But the agreement needs to be renegotiated for the SKA before construction starts.
Quelle: nature
Update: 24.12.2016

In African desert, telescope project seeks clear skies in cruel terrain

The Square Kilometre Array will be the world’s most powerful radio telescope, opening new frontiers in our understanding of the universe. But the builders have to contend with an unforgiving climate and other formidable challenges first,Geoffrey York reports

The world’s most powerful telescope, known as the Square Kilometre Array, which is currently under construction in a remote region of South Africa.

The world’s most powerful radio telescope, a Canadian-backed project known as the Square Kilometre Array, is currently under construction in a remote region of South Africa.


In the desolate rocky plains of the Great Karoo, the dangers are endless. Scorpions and puff adders are underfoot. The harsh sun beats down, interrupted only by occasional lightning storms. Temperatures range from stifling heat to freezing cold. 

But at night, in the vast empty darkness, the stars are impossibly bright and clear. And it is the stars that have lured a Canadian-backed project to build the world’s most powerful radio telescope, with the potential to unlock the deepest secrets of the universe. 

For the engineers who are now assembling the telescope in this forbidding landscape, the wind whipping down from the Karoo hills is one of the main worries. Gusts of wind can flip over the giant 13.5-metre-wide dish antennas that form the telescope, so construction is halted as soon as the wind rises. 

Yet, the biggest threats are invisible: signals from a cellphone or laptop, emitting enough interference to destroy a day of data from the antennas. To combat this hazard, electronic devices are banned for many kilometres around the site, or kept in underground bunkers behind heavily shielded doors. 

The challenges of this pioneering telescope project are extraordinary, but the payoff will be spectacular. The sprawling collection of radio antennas, dubbed the Square Kilometre Array (SKA) because of an early estimate of the size of their collecting surface, could some day find clues to the origins of the universe, the forces that create planets, the nature of dark matter, and the mysteries of possible life in other galaxies. 


Like the thousands of receptors in the compound eye of a fly, the project will build its image of the universe from thousands of futuristic antennas, resembling satellite dishes, which will be electronically combined with the help of Canadian technology. 

The South African antennas, although still in an early precursor phase, have already discovered more than 1,300 galaxies in a patch of sky where only 70 were previously known to exist. The images stunned astronomers around the world when they were revealed in July. 

The full telescope, to be completed by 2024, will be physically divided between South Africa and Australia. But eight other countries, including Canada, will be key partners in the consortium that supports the $2-billion (U.S.) project. 

Negotiations among the consortium members, now under way, will set up a council to determine the size of the financial and technological investments by Canada and the other partners. Canada has some of the world’s leading expertise in the supercomputers and correlators that will be crucial to the telescope project. 

Here in the remote Karoo flatland, sheep farmers and townsfolk are wary of the project, fearing the potential expropriation of their land and the silencing of their telecommunications. Across a vast swath of 132,000 hectares of farmland, a traditional way of life could be lost, and some farmers are skeptical of whether the science-related jobs will be enough to replace it. “Precious agricultural land is under threat,” says a group called Save the Karoo. 

Yet, the project’s benefits are huge. The telescope will be far more sensitive than anything else in existence, allowing far fainter signals to be analyzed. 

“The most profound questions that a philosopher might ask are: ‘What is the universe made of’ and ‘Are we alone?’” said Bryan Gaensler, the Canadian SKA science director. 

“And the SKA is aiming to answer both of those questions – as well as others, like ‘how did everything begin, how will it end.’ These are all really deep questions that people have been asking for centuries, and nobody ever thought there would be answers to them,” Mr. Gaensler told The Globe and Mail in an interview. 

“We’ll be able to watch planets form, and then understand if there’s life on them. It’s exciting. When I started to see the preliminary images, I was just blown away.” 

Those first images were produced from just 16 of the planned 64 antennas in the SKA’s first phase, known as MeerKAT. (The name is derived from an earlier precursor, the Karoo Array Telescope, with a nod to the popular African desert mammal and the Afrikaans word for “more.”) 

The Globe was recently allowed to visit the guarded MeerKAT site, at the end of a dusty, 90-kilometre drive from the nearest town. Road signs warned of wandering sheep, but there were few signs of life, aside from stony fields of scrub bush and cactus and the occasional lonely farm building. 

Watch: A flyover view of the South African array

The full telescope will be physically divided between South Africa and Australia, and is due to be finished by 2024.SKA SA

Engineers disclosed that they have now erected 34 antennas and are hoping to finish the 64th antenna by October, 2017. Many of the gleaming white antennas are already linked into the computers. Their cooling systems are humming in the mid-day heat, their wind detectors are monitoring the breezes, and there is a quiet whirring noise as the giant dishes are adjusted to focus on a new spot in the sky. 

The antennas here will produce such an overwhelming tsunami of Big Data that powerful supercomputers will be needed to process it. Not far from the antennas is an underground bunker, where data processing computers will be housed in so-called Faraday cages, behind sliding metal doors, to prevent them from emitting radio interference. The data flow is so massive that it is compressed here, before being transmitted to research centres for analysis. 

In a nearby dormitory for the project’s staff, the house rules say: “Personal electronic devices may only be used in shielded rooms.” Red and black “danger” signs are posted on the walls, warning: “No bluetooth, no cellphones, no wifi. Your radio signals will damage our equipment.” 

Even ordinary gasoline-powered vehicles are barred from the site, because their spark plugs can cause interference. Only diesel vehicles are used, to protect the precious data arriving from the dishes. 

“In the old days, the cost of the telescope was the metal beams, but these days there’s a recognition that the supercomputer attached to the telescope is what creates the magic and the potential for discovery,” Mr. Gaensler said. 

“The philosophy now is that the computer is the telescope. It’s a whole new way of doing science. It’s not about getting the sharpest, prettiest picture – it’s about dealing with incredible torrents of data and finding the needles in the haystacks.” 

The computers will be crucial because the SKA will generate data volumes that can be measured in exabytes (one billion gigabytes). It will be bigger than the current data rate of the entire Internet. 

“It’s a big challenge, because we’re pushing into realms of processing terrain that we haven’t seen before,” said Sean Dougherty, director of the Dominion Radio Astrophysical Observatory in Penticton, B.C. 

“We’ve only visited it for very brief moments in experiments like the Large Hadron Collider. That’s quite different from the model of the SKA, where data-taking will go over many hours, so the volumes of data are going to be unprecedented.” 


Canadian-designed supercomputers will help the telescope generate images by combining the signals from the antennas. 


Unlike optical telescopes, a radio telescope can peer through the thick layers of dust surrounding the galaxies. And because of its South African location, it will provide a much clearer view of the heart of our own galaxy, the Milky Way, which is more readily visible from the Southern Hemisphere. 

Canada, led by the National Research Council and a group of Canadian universities, was one of the six founding members of the earliest SKA consortium in 2000. Today, it is one of 10 member countries in the SKA Organization and appoints two representatives to the SKA board of directors. 

The National Research Council is already supplying technology to the MeerKAT antennas in South Africa, including low-noise amplifiers for the radio receivers. It also helped develop cost-effective carbon-fiber composite materials for use in the receiver systems. 

And Canada has world-leading expertise in designing the supercomputers and correlators that will generate the images from the SKA telescope by combining the signals from the antennas. 

“There’s an enormous Canadian contribution,” Mr. Gaensler said. “We really hope to see, in a metaphorical sense, Made-in-Canada stickers all over the equipment and all over the discoveries.” 

Canadian astronomers are among the world’s leading experts on some of the SKA’s science priorities – including the study of pulsars to understand gravity, and the detection of atomic hydrogen to learn how the universe evolved. 

“We can figure out how the first galaxies formed, how the first stars formed,” Mr. Dougherty told The Globe. 

“There will be interesting phenomena we’ll discover that we had no idea existed before. The Southern Hemisphere, unlike the Northern Hemisphere, has really been starved of significant collecting areas. When you’ve got more collecting area, the images are much more sensitive, so you can go deeper and see fainter objects.” 

The SKA is a huge boost for African science, with spinoffs aiming to strengthen radio astronomy in eight other African nations. Canada is helping organize a conference of African astronomers in Mauritius in May to hear their proposals for SKA research. 

The small Karoo towns near the telescope site, where unemployment is high, are among the beneficiaries of jobs and education from the project. Supporters argue that the telescope is the biggest windfall for this corner of the Karoo since the “wool boom” of the 1950s, when sheep briefly became a high-value commodity. 

The South African SKA organization is paying for the recruitment of math and science teachers at a high school in Carnarvon, the nearest town. It has awarded more than 100 bursaries for students to attend the school, and it has donated hundreds of computers to Carnarvon’s schools and library. 

In 2015, for the first time in the history of the Carnarvon high school, five of its students passed their university qualifying exams in math and science. Today, they are studying physics and computer science at university, potential astronomers of the future.

Quelle: The Globe and Mail


Update: 8.07.2017


Ghana and South Africa celebrate first success of African network of telescopes


The Ministries of Ghana and South Africa announce the combination of ‘first light’ science observations which confirm the successful conversion of the Ghana communications antenna from a redundant telecoms instrument into a functioning Very Long Baseline Interferometry (VLBI) radio telescope.

Ghana is the first partner country of the African Very Long Baseline Interferometer (VLBI) Network (AVN) to complete the conversion of a communications antenna into a functioning radio telescope. The 32-metre converted telecommunications antenna at the Ghana Intelsat Satellite Earth Station at Kutunse will be integrated into the African VLBI Network (AVN) in preparation for the second phase construction of the Square Kilometre Array (SKA) across the African continent. The combination ‘first light’ science observations included Methanol Maser detections, VLBI fringe testing and Pulsar observations. Reaching these three objectives confirm that the instrument can operate as a single dish radio telescope and also as part of global VLBI network observations, such as the European VLBI network. Following the initial ‘first light’ observations, the research teams from Ghana and South Africa together with other international research partners, continue to do more observations and are analysing the data generated with the aim to characterise the system and improve its accuracy for future experiments.

“The Ghanaian government warmly embraces the prospect of radio astronomy in the country and our radio astronomy development plan forms part of the broader Ghana Science, Technology and Innovation Development Plan,” says Professor Kwabena Frimpong-Boateng, the Ghana Minister of Environment, Science, Technology and Innovation (MESTI). As an SKA Africa partner country, Ghana welcomed and collaborated with the SKA South Africa (SKA SA)/HartRAO (Hartebeesthoek Radio Astronomy Observatory) group to harness the radio astronomy potential of the redundant satellite communication antenna at Kutunse. A team of scientists and engineers from SKA SA/HartRAO and the Ghana Space Science and Technology Institute (GSSTI) which is under MESTI, has been working since 2011 on the astronomy instrument upgrade to make it radio-astronomy ready. In 2012, Ghana launched the GSSTI as the vehicle through which to grow its astro-physics programme.

The South African Department of International Relations and Cooperation (DIRCO) has been funding a large part of the conversion project through the African Renaissance and International Cooperation Fund (ARF). The South African Minister of DIRCO, Ms Maite Nkoana-Mashabane says, “The African Renaissance Fund is aimed at strengthening cooperation between South Africa and other African countries and to support the development of skills and build institutional capacity on the continent.” Nine African partner countries are members of the SKA AVN, including Botswana, Ghana, Kenya, Madagascar, Mauritius, Mozambique, Namibia, South Africa, and Zambia.

“A vital part of the effort towards building SKA on the African Continent over the next decade is to develop the skills, regulations and institutional capacity needed in SKA partner countries to optimise African participation in the SKA,” says the South African Minister of Science and Technology, Mrs Naledi Pandor. The AVN programme is aimed at transferring skills and knowledge in African partner countries to build, maintain, operate and use radio telescopes. Minister Pandor continued by saying: “It will bring new science opportunities to Africa on a relatively short time scale and develop radio astronomy science communities in SKA partner countries.”

The Leverhulme-Royal Society Trust and Newton Fund in the UK are co-funding extensive human capital development programmes in the SKA AVN partner countries. A seven-member Ghanaian team has undergone training in South Africa and have been trained in all aspects of the project including the operation of the telescope. Several PhD students and one MSc student from Ghana have received SKA SA bursaries to pursue further education in various fields of astronomy and engineering while the Royal Society has awarded funding in collaboration with Leeds University to train two PhDs and 60 young aspiring scientists in the field of astrophysics. Based on the success of the Leverhulme-Royal Society programme, a joint UK-South Africa Newton Fund intervention (the Development in Africa with Radio Astronomy (DARA)) has since been initiated in other partner countries to grow high technology skills that could lead to broader economic development in Africa. This Newton Fund programme is providing a pool of talented young people who have been inspired by astronomy to ultimately play a leading role in the emergence of new economies.

A Ministerial Forum comprising Ministers from the nine SKA AVN partner countries convenes on an annual basis to provide strategic and political leadership on the cooperation with the SKA and AVN projects, and on other relevant radio astronomy programmes and initiatives. The next SKA AVN Ministerial Forum will be held in Accra, Ghana in August when the Kutunse radio telescope will officially be launched.


Notes to Editors

The Ghana Intelsat Satellite Earth Station at Kutunse is situated at an elevation of 70 metres above sea level. Kutunse is a suburb located about 25 kilometres north-west of the national capital, Accra. The station was commissioned on 12 August 1981, and was operated by the Ghana Telecommunications Corporation until 3 July 2008, when Ghana Vodafone took over as major shareholder with a 70% share of the station. The SKA SA/HartRAO team assessed the suitability of the 32-metre Beam Waveguide antenna and the Kutunse control station for radio astronomy through two successive working visits in March and May 2011. The conversion work started when the station was handed over from Vodafone to the Ghanaian state under the management of GSSTI.

Once the refurbishment and conversion was completed, a commissioning team looked at how the telescope performed during the process of blind tracking and how it is affected by factors such as gravity as the antenna rotates. The team checked the effect of Radio Frequency Interference (RFI) and how well the antenna does a full rotation. For Phase 1, the existing telecommunication feed horn was used in the frequency range 3.8 – 6.4 GHz (C-band). For the actual science observations (Phase 2), an uncooled 5 GHz and 6.7 GHz (C-band) receivers were fitted.

Future receiver developments may include replacing the original C-band feed horn with a wider band design covering more VLBI bands and introducing cryogenic receivers for improved sensitivity and adding more frequency bands. Future changes could be according to the science programme of the GSSTI, in collaboration with global partners.

The science requirements
The newly refurbished radio telescope has two modes of operation: to form part of global VLBI networks (including the African VLBI Network, as it grows) and also operate as a single radio telescope. To meet both these needs, each function has its own set of required capabilities that the station has to satisfy. Ghana will lead and determine the single dish programme.

For the single-dish component, the uncooled C-band receivers have been fitted. This allows the antenna to do: radio continuum flux measurements (with a wideband multi-channel radiometer); pulsar observations (with a wideband multi-channel pulsar timer); and emission lines spectroscopy (with a narrowband multi-channel spectrometer).

For the VLBI component, the station requires capacity for: mapping interstellar masers in star-forming regions in the Milky Way; determining the distances to star-forming regions in the Milky Way through methanol maser parallax measurements; using trigonometric parallax measurements to determine accurate pulsar distances as well as pulsar proper motions; imaging active galactic nuclei (AGN); and other important functionalities. The longitude and latitude geographic location of the station is significant for astrophysics research.

‘First Light’ observations

  1. Methanol Maser detection
    The detection of masers has been a priority goal since the start of the engineering commissioning phase of Kutunse radio telescope. Not only were maser detections one of the three major objectives of the engineering commissioning phase, it also supported the Leverhulme-Royal Society Trust training objectives.

    The first observations aimed at the detection of a maser (G9.621+0.196E) were carried out on 21 November 2016. Since the initial detection other masers have been detected routinely.

  2. Fringe test
    In VLBI (Very Long Baseline Interferometry), signals from an astronomical radio source such as a quasar are collected at multiple radio telescopes on Earth. Data received at each antenna in the array include precise time stamping from a local atomic clock, such as a hydrogen maser. Off line, the data are correlated to remove the arrival time delays of the signal and derive a band of contrasting brightness produced by the interference of the signals from antenna pairs (fringes). The resolution achievable using interferometry is also proportional to the observing frequency. The VLBI technique enables the distance between telescopes to be much greater than that possible with conventional interferometry, which requires antennas to be physically connected by coaxial cable, waveguide, optical fibre, or other types of transmission lines.

    VLBI is most well-known for imaging distant cosmic radio sources, spacecraft tracking, and for applications in astrometry. However, since the VLBI technique measures the time differences between the arrival of radio waves at separate antennas, it can also be used “in reverse” to perform earth rotation studies, map movements of tectonic plates very precisely, and perform other types of geodesy. Using VLBI in this manner requires large numbers of time difference measurements from distant sources (such as quasars) observed with a global network of antennas over a period of time.

    The Kutunse telescope ‘gate-crashed’ one of the C-band VLBI test observations that was carried out on 28 February 2017. The European VLBI Network supported the observation from Kutunse with great enthusiasm and assisted in the data analysis and correlation through experts from the Joint Institute for VLBI (JIVE) European Infrastructure Research Consortium (ERIC) in the Netherlands.

  3. Pulsar observations
    The primary initial goal for Kutunse pulsar observations was to detect a known pulsar at the correct period, demonstrating basic time-domain functionality. On the 30th of April 2017, Professor Ben Stappers and his students Tom Scragg from the University of Manchester, alongside the SKA South African and Ghanaian team, made observations of two pulsars at Kutunse using the 5 GHz receiver.

Collaborators and acknowledgments

The following groups of individuals and institutions are recognised for the participation, collaboration and support in realising this momentous milestone.

The telescopes involved in the successful detection of fringes during a VLBI test experiment were part of the European VLBI Network (EVN) and included: Badary Radio Astronomical Observatory (Institute of Applied Astronomy, Russia), Effelsberg Radio Telescope (Max-Planck Institute for Radio Astronomy, Germany), Hartebeesthoek Radio Astronomy Observatory (National Research Foundation, South Africa), Jodrell Bank Observatory (University of Manchester, UK), Medicina Radio Observatory (National Institute for Astrophysics, Italy), Onsala Space Observatory (Chalmers University of Technology, Sweden), Svetloe Radio Astronomical Observatory (Institute of Applied Astronomy, Russia), Toruń Centre for Astronomy (Nicolaus Copernicus University, Poland), Ürümqi Astronomical Observatory (Chinese Academy of Sciences, China), Ventspils International Radio Astronomy Centre (Latvian Academy of Sciences, Latvia), Westerbork Synthesis Radio Telescope (ASTRON, the Netherlands), Yebes Observatory (National Geographic Institute, Spain), and Zelenchukskaya Observatory (Institute of Applied Astronomy, Russia).

The scientists at the JIVE ERIC in the Netherlands and the broader European network added tremendous value through Dr Jay Blanchard, Support Scientist for the JUMPING JIVE project.

For the pulsar timer, Professor Ben Stappers, University of Manchester and his student Mr Tom Scragg, University of Manchester, were key contributors, also providing equipment funded through the Leverhulme-Royal Society intervention.

Professor Melvin Hoare, Leeds University was responsible for the Leverhulme-Royal Society programme.

Quelle: SKA


Tags: Radioteleskop (Square Kilometre Array) SKA) Astronomie - Radioteleskop (Square Kilometre Array) SKA) in Südafrika-Update-2 Astronomie 


Samstag, 8. Juli 2017 - 20:15 Uhr

Raumfahrt - Ghana startet seinen ersten Satelliten (GhanaSat-1) in den Weltraum


Ghana launches its first satellite into space


The development team behind the satellite

Ghana has successfully launched its first satellite into space.

GhanaSat-1, which was developed by students at All Nations University in Koforidua, was sent into orbit from the International Space Centre.

Cheers erupted as 400 people, including the engineers, gathered in the southern Ghanaian city to watch live pictures of the launch. The first signal was received shortly afterwards.

It is the culmination of a two-year project, costing $50,000 (£40,000).

It received support from the Japan Aerospace Exploration Agency (JAXA).

The satellite will be used to monitor Ghana's coastline for mapping purposes, and to build capacity in space science and technology. 

Project coordinator Dr Richard Damoah said it marked a new beginning for the country.

"It has opened the door for us to do a lot of activities from space," he told the BBC. 

He said it would "also help us train the upcoming generation on how to apply satellites in different activities around our region.

"For instance, [monitoring] illegal mining is one of the things we are looking to accomplish."

 Quelle: BBC

Tags: Raumfahrt - Ghana startet seinen ersten Satelliten (GhanaSat-1) in den Weltraum 


Samstag, 8. Juli 2017 - 07:45 Uhr



“ . . . the Mars landing may signal the start of a new interactive era in the mass consumption of news . . . “
– The New York Times, July 14, 1997


Twenty years ago, NASA landed a little rover on Mars . . . and blew up the Internet. As people clamored for pictures – overwhelming servers and bringing network traffic to a standstill – it became obvious that something fundamental had changed on how people expected to get information about NASA missions.

Image Credit: NASA

NASA, through its Jet Propulsion Laboratory in California, had begun to release information online following Voyager’s encounters with Uranus and Neptune in the 1980s.

“When I arrived at JPL in 1985, I was already active in some of the online networks of the day such as CompuServe, so distributing pictures and information about NASA missions that way seemed natural,” said former JPL public information manager Frank O’Donnell. “Also, Ron Baalke at JPL was very active posting information to Usenet, the Internet-based system of newsgroups. At the end of the '80s, I established a dialup bulletin board system at JPL, which members of the public could dial into directly to download pictures and text files.”

Then, in 1993, came the discovery of Comet Shoemaker-Levy 9, and astronomers’ realization that it would hit Jupiter in July 1994. By then scientists were communicating by e-mail, transferring large files around the world and posting their work for discussion on the nascent World Wide Web. Now they were using those tools to plan worldwide campaign to observe the collision

NASA’s public affairs office followed suit, scheduling briefings throughout the encounter. (The comet had fragmented into numerous pieces that would arrive at Jupiter over several days.) The schedule published the time images were expected to be received and when they would be discussed on NASA TV.

Naturally, Internet users started banging on NASA websites a few minutes before the pictures were scheduled to be downlinked, unable to wait until the scheduled release time. As Philip C. Plait wrote in “Bad Astronomy”, “. . . the web nearly screeched to a halt due to the overwhelming amount of traffic as people tried to find pictures of the event from different observatories.”

The excitement wasn’t limited to the public. Scientists found themselves doing their work live on NASA TV, as this clip from a National Geographic special shows. By coincidence it was also around this time that NASA’s Office of Public Affairs announced that it would no longer mail news releases to reporters, but would instead distribute them online.

The impact site of one of comet SL9's fragments on Jupiter's cloud-tops.


Shoemaker-Levy made it clear to JPL they would have to prepare for something even bigger with Mars Pathfinder. Webmaster David Dubov told the New York Times shortly after the landing that he estimated the site would be receiving 25 million hits a day. (A “hit” is a request for information from one computer to another. On the web, a hit can represent the transfer of a picture, text or other page element. In the case of Pathfinder’s deliberately stripped-down site, each web page comprised a few hits.)

Dubov and JPL engineer Kirk Goodall would later revise that estimate to 60-80 million hits a day, traffic that would crash JPL’s networks if the servers were hosted there. Goodall set out to build a network of mirror sites that could take the traffic off JPL’s networks. Working with other U.S. science agencies, and ultimately corporations and Internet “backbone” providers, he did just that. (In other words, JPL crowd-sourced their solution a couple of decades before anyone knew crowdsourcing was a thing.)

And the solution worked. The site took 30 million hits on landing day, July 4. On July 7, the first weekday after the landing, the site got 80 million hits. In comparison, the year before, the chess match between Gary Kasparov and IBM’s Deep Blue computer peaked at 21 million hits, and the Atlanta Olympics website had topped out at 18 million hits on one day. 



“One of the biggest changes with Mars Pathfinder was that it was the first mission that fully embraced the Internet as a primary way of getting out information to the public,” said O’Donnell. “Before Pathfinder, the prevailing thinking was that eight-by-ten photo prints were the product needed for the public at large.”

It’s worth remembering how the public got to see NASA images before the Internet era. NASA teams would review the raw images, select a few and distribute them as physical prints at news conferences. Media had to be in attendance at the conference to get a copy. Most newspapers and TV stations had to wait until a wire service had scanned the image and sent it out over their proprietary network.

Most people might see a new image every day for a few days. A week later there might be a few more images published in weekly news magazines. Maybe six or eight months later, a magazine like National Geographic might publish a long story with a dozen or more additional images. Most people never saw more than a handful of pictures from NASA missions.

Image Credit: NASA

The Pathfinder team had to take “photo prints and scan them in order to post digital files online,” said O’Donnell. “Pathfinder's teams committed to releasing direct-to-digital files very quickly.”

“And the public loved it.” he added.

“I remember sitting at my desk clicking on picture after picture,” said Bob Jacobs, now NASA’s deputy associate administrator for communications, but then with the Associated Press. “I could see so much more from this mission than it ever had before, and I came back day after day.”

Not everyone was happy. IT staffs around the world found themselves dealing with unprecedented amounts of traffic on their local networks, sometimes to the breaking point. In France, where the same networks were carrying telephone and Internet traffic, the government took the unprecedented step of asking people not visit the websites, since it was affecting phone service. At NASA Headquarters, which had an indirect Internet connection through a NASA center handled traffic to its web servers through the same “pipe” as business services, saw very slow performance for e-mail and other business operations on July 7.


NASA Online

Mars Pathfinder changed forever how the public expected to get information on NASA missions, and on any other live event. Instead of waiting for news reports, the public expected to join in as the event happened and see results in real time. By the time NASA’s next rovers, Spirit and Opportunity, landed on Mars in 2004, NASA had moved its web infrastructure to into a commercial data center and added a commercial caching network. The change allowed NASA to handle even more traffic, 109 million hits in 24 hours, including having 50,000 people watching NASA TV’s coverage of the landings via webcast.

NASA online offerings continue to evolve. Now nearing the end of its mission, Cassini has been sending back raw images from Saturn and its moons since 2005, and they have been made immediately available to the public. NASA’s Mars missions have similar sites. The Hubble Space Telescope has made thousands of images available online. With the advent of social media, people can share and talk about images immediately.

Image Credit: NASA

It isn’t just pictures that are available immediately. When the Mars Science Laboratory landed on Mars in 2012, more than 1.2 million people watched NASA TV’s coverage live over the Internet. For February’s announcement of the TRAPPIST-1 exoplanets, more than a million people watched the press conference, and there were more than 500,000 social media mentions from outside NASA. We’re expecting similar numbers, if not more, for the Aug. 21 solar eclipse.

Social media has become the new communications frontier for NASA. When the Mars Phoenix lander arrived at the Red Planet, JPL’s public affairs team took to Twitter and started posting updates in the voice of the spacecraft. "We created the account, known as Mars Phoenix, last May with the goal of providing the public with near real-time updates on the mission," Veronica McGregor, manager of the JPL news office and originator of the updates, said in 2009. "The response was incredible. Very quickly it became a way not only to deliver news of the mission, but to interact with the public and respond to their questions about space exploration." 

The excitement of space exploration is now available more quickly to more people more directly than it ever has been, and that trend seems only like to accelerate. For the solar eclipse, NASA will deploy television cameras, scientists and communicators across the United States, allowing anyone around the world to participate. For an agency with the mission to make the results of its missions known “to the widest extent practicable” – as required by the law that created NASA -- these are very exciting times. Who knows? Maybe one day we can make the Internet stand still again.

Quelle: NASA


Samstag, 8. Juli 2017 - 07:30 Uhr

Astronomie - Hubble’s Hidden Galaxy



IC 342 is a challenging cosmic target. Although it is bright, the galaxy sits near the equator of the Milky Way’s galactic disk, where the sky is thick with glowing cosmic gas, bright stars, and dark, obscuring dust. In order for astronomers to see the intricate spiral structure of IC 342, they must gaze through a large amount of material contained within our own galaxy — no easy feat! As a result IC 342 is relatively difficult to spot and image, giving rise to its intriguing nickname: the “Hidden Galaxy.”

Located very close (in astronomical terms) to the Milky Way, this sweeping spiral galaxy would be among the brightest in the sky were it not for its dust-obscured location. The galaxy is very active, as indicated by the range of colors visible in this NASA/ESA Hubble Space Telescope image, depicting the very central region of the galaxy. A beautiful mixture of hot, blue star-forming regions, redder, cooler regions of gas, and dark lanes of opaque dust can be seen, all swirling together around a bright core. In 2003, astronomers confirmed this core to be a specific type of central region known as an HII nucleus — a name that indicates the presence of ionized hydrogen — that is likely to be creating many hot new stars.

Quelle: NASA

Tags: Astronomie - Hubble’s Hidden Galaxy 


Freitag, 7. Juli 2017 - 21:10 Uhr

Raumfahrt - Merkur Mission BepiColombo 2017 - Update-1



Artist’s concept of the BepiColombo mission, showing the European-built Mercury Planetary Orbiter (top) and the Japanese Mercury Magnetospheric Orbiter (bottom). Credit: ESA
The launch of a nearly $2 billion joint mission robotic mission to Mercury by Europe and Japan will be delayed from next year to early 2017 to account for late deliveries of critical components and scientific instrumentation, according to the European Space Agency.
The BepiColombo mission, comprising two main spacecraft built in Europe and Japan, will still reach Mercury in January 2024.
The new launch window — determined by the positions of the planets — opens on Jan. 27, 2017, and extends for one month, ESA announced March 30. The launch was previously set for July 2016.
Mission managers completed BepiColombo’s critical design review March 25 and decided to put off the launch for six months.
“As the result of delays in the procurement of critical units and the availability of some payloads, a decision was taken to opt for a later launch opportunity in order to minimize the operational risk to this ambitious dual mission,” ESA said in a statement.
Another launch opportunity is available in mid-2017 to allow BepiColombo to still get to Mercury in 2024.
BepiColombo will launch on an Ariane 5 rocket from the Guiana Space Center in South America to kick off a seven-year cruise through the inner solar system. The European and Japanese components will blast off with a carrier spacecraft called the Mercury Transfer Module, which will carry ion engines to guide the mission on the journey to Mercury.
A mock-up of the BepiColombo composite spacecraft in launch configuration undergoes shaker testing in July 2012. Credit: ESA
When packaged inside the Ariane 5’s payload fairing, the three-part spacecraft stack will measure about the size of a moving van.
The spacecraft will return to the vicinity of Earth in July 2018 for a gravity boost to slingshot the probe closer to the sun. BepiColombo will spiral toward Mercury with two flybys of Venus in September 2019 and May 2020, followed by five Mercury encounters between 2020 and 2023.
BepiColombo’s transit module will be jettisoned just before it steers into orbit around Mercury on Jan. 1, 2024. The mission’s Japanese and European components — each fully functioning spacecraft — will separate and fly into different orbits for at least one year of observations, looking at the planet’s cratered surface, investigating its origin, probing its interior, examining its tenuous atmosphere, studying its magnetic field, and timing Mercury’s orbit around the sun to test Albert Einstein’s theory of general relativity.
Mercury will fly around the sun four times during BepiColombo’s one-year prime mission. The orbiters should have enough fuel for a one-year extension.
BepiColombo’s Japanese section — known as the Mercury Magnetospheric Orbiter — is about the size of a compact car. It will probe Mercury’s magnetic field and atmosphere from a highly elliptical orbit.
ESA’s Mercury Planetary Orbiter will fly closer to the planet’s surface, measuring Mercury’s terrain and composition.
BepiColombo’s Mercury Planetary Orbiter is seen inside a clean room at ESA’s test center in Noordwijk, the Netherlands. Credit: ESA – A. Le Floc’h
BepiColombo will be the first mission to Mercury by Europe and Japan, and the second to orbit the fleet-footed planet after NASA’s Messenger spacecraft.
First proposed to ESA in the 1990s, BepiColombo is one of the most difficult space missions ever attempted by Europe and the most ambitious probe ever sent to Mercury. Powered by ion engines and shielded to withstand scorching temperatures of nearly 700 degrees Fahrenheit at Mercury, BepiColombo has endured redesigns, upgrades and delays that have sent the mission’s cost more than 50 percent higher than original estimates.
ESA officials intended BepiColombo to launch on a medium-class Soyuz rocket, but the spacecraft outgrew the capacity of the Soyuz, forcing it to lift off on the more expensive Ariane 5.
Technicians in February mated BepiColombo’s European orbiter and transfer module for the first time at ESA’s test center in the Netherlands. Japan’s magnetospheric probe is due to arrive at ESA in April for final tests.
Quelle: SN
Update: 21.04.2015
The BepiColombo probe to examine Mercury, the largely unexplored planet closest to the Sun
The mission comprises a composite of two orbiters and two supporting modules which are launched in a four-module stack configuration. The orbiters are the Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO). The supporting modules are the Mercury Transfer Module (MTM) and the MMO Sunshade and Interface Structure (MOSIF). The prime contractor for the mission is Airbus Defence and Space.  ESA is providing the MPO, MTM and MOSIF. JAXA will supply the MMO. The mission is slated for launch in 2017. On arrival at Mercury in 2024 it will gather data for at least one year.
Quelle: Airbus DEFENCE&SPACE
Update: 22.07.2015


The antenna that will connect Europe’s BepiColombo with Earth is being tested for the extreme conditions it must endure orbiting Mercury.
The trial is taking place over 10 days inside ESA’s Large Space Simulator, which, at 15 m high and 10 m across, is cavernous enough to accommodate an upended double decker bus.
The 1.5 m-diameter high-gain antenna, plus its boom and support structure, are subjected to a shaft of intense sunlight in vacuum conditions, while gradually rotated through 90º.
The antenna will be part of ESA’s Mercury Planetary Orbiter, one of two main components of the January 2017 BepiColombo mission – the other being Japan’s Mercury Magnetospheric Orbiter.
The two will be launched together in a stack, carried by the Mercury Transfer Module for their seven-year journey towards the Solar System’s innermost world.
The Simulator is part of the largest spacecraft testing facility in Europe, at ESA’s ESTEC technical centre in Noordwijk, the Netherlands.
The mammoth chamber’s high-performance pumps create a vacuum a billion times lower than standard sea-level atmosphere, while the chamber’s black interior walls are lined with tubes pumped full of –190°C liquid nitrogen to mimic the extreme cold of deep space.
At the same time, the hexagonal mirrors seen at the top of the picture reflect simulated sunlight onto the satellite from a set of 25 kW bulbs more typically employed to project IMAX movies.
In this case, the alignment of the 121 mirrors was adjusted to tighten the focus of their light beam, reproducing the intensity of sunlight experienced in Mercury orbit – around 10 times more intense than terrestrial illumination.
Quelle: ESA
Siehe auch:
Update: 28.12.2015
The Mercury Planetary Orbiter (MPO) is a three-axis stabilised spacecraft which will orbit Mercury in an inertial polar orbit of 2.3h period. It accommodates 11 instruments or instrument suites and has a box-like shape of 3.9 x 2.2 x 1.7 m.
The radiator, on the -Y side, will always face away from the Sun (the MPO will flip by 180º at perihelion and aphelion, meaning both -X and +X sides will face in the ram direction), and most of the instruments are on the -Z side, which will nominally always face towards Mercury (i.e. nadir). The altitude range is expected to be 480 km to 1500 km, with the latitude of the periherm varying between 16ºN to 16ºS over the course of the nominal science phase (i.e. the first full Earth year).
As can be seen in the orbit figure below, at perihelion, the MPO's apoherm is on the dayside - this configuration minimises the thermal load, both from the Sun and from Mercury's albedo. The perihelion is an important time for the exospheric instruments; at perihelion the planet's spin speed is slightly overtaken by the orbit speed, and from the surface the Sun would appear to slow down, stop, go in the other direction for ~4 (Earth) days, then slow, stop and continue in the ‘correct' direction - the dawn and dusk effectively swap. 
The aphelion time is the most important for the cameras and surface scanning instruments, while the periherm is in the dayside, i.e. the surface is lit and close so that the cameras can get good resolution.
Diagram describing schematically how the periherm and apoherm vary throughout the Mercury year.
Four redundant 22N thrusters in the nadir face to be used in orbital manoeuvres until final orbit acquisition, after which they will be deactivated. The control of the attitude is provided by a set of four reaction wheels and four 10N thrusters for momentum wheel de-saturation; these thrusters are mounted on the radiator. Three star trackers, also mounted on the radiator side, sun sensors and a high precision gyroscope package are employed as sensors for attitude control, the combination of which provides precise attitude determination required by several of the instruments.
The only side of the spacecraft not to see the Sun is the radiator; highly reflective fins (polished and geometrically reflecting outwards) have been mounted to it at an appropriate angle, to minimize absorption of heat radiated from Mercury, and to allow radiation towards deep space. 
Because of the intense heat, the three-panel solar array is a 70-30% mixture of solar cells and Optical Surface Reflectors (OSR, i.e. mirrors) to keep its temperature below 200°C. This is supported by choosing sun incident angles up to 80° that generate enough power, but do not unnecessarily heat up the solar array. There is a battery and heaters that operate in the freezing dark during eclipse.
The Mercury Magnetospheric Orbiter (MMO) is a spin-axis stabilised spacecraft with a rotation rate of 15 rpm or spin period of 4s; the spin axis will be nearly perpendicular to Mercury's equator. Altitude range is currently expected to be from 590 km to 11639 km – the apoherm is nearly 6 planetary radii from planet's centre.
The main body of the spacecraft is octagonal and would fit inside a circle of 1.8 m diameter. The height of side panel is 0.9 m; the upper portion is 50% solar cells and 50% optical solar reflectors (OSRs). There are two decks (upper and lower)separated by 40 cm that hold the instruments, a central cylinder (thrust tube) and four bulkheads.
MMO structure (side view) (after Fig. 4, Yamakawa et al., 2008).
The spacecraft attitude will be determined by a pair of sun sensors on the side panel and a star scanner attached to the bottom surface. The attitude is controlled by the propulsion system with a cold gas jet. A nutation dumper installed inside the central cylinder is used for passive nutation dumping.
The MMO carries as payload:
MDM - Mercury Dust Monitor
MGF - Magnetometer
MPPE - Mercury Plasma Particle Experiment
MSASI - Mercury Sodium Atmospheric Spectral Imager
PWI - Plasma Wave Investigation
The figure below shows how the sensors and electronics/receivers fit together. All of the inputs to DPU1 are from the MPPE suite, and inputs from the other four suites/instruments are routed to DPU2.
External view of the MMO spacecraft and PWI sensors (after Fig 3., Kasaba et al.,
The labelled mast is referred to as MAST-SC and the unlabelled mast is termed MAST-MGF and holds the MGF dual-sensor instrument. The antennas are PWI's WPT and MEFISTO (electric-field sensors), which measure 32 m tip-to-tip, or 15 m each from the s/c.
Detailed view of the extendable mast system (after Fig. 25, Kasaba et al., 2010).
One mast (MAST-MGF) holds MMO/MGF (dual fluxgate magnetometer; MGF-O at the tip and MGF-I 1.6 m from the tip) and the other mast (MAST-SC) holds both PWI's LF-SC (Low-Frequency Search Coils) and DB-SC (Dual-Band Search Coils) at the tip. Extension of the masts will be performed in the initial phase of the MMO operation just after the separation of the MMO from the MCS (Mercury Composite Spacecraft) at the Mercury orbit.
The trajectory of the MMO spacecraft. MSASI observations may be performed
during an interval of 3h 25m between periapsis and apoapsis (the red arc) (after
Fig. 1., Yoshikawa et al., 2010).
As the spin axis is in the same direction as the spin axis of Mercury, the spacecraft will remain ‘upright' throughout the orbit around Mercury; the bottom of the lower deck (radiator and second surface mirror (SSM)) and the top of the upper deck (MLI) will be able to ‘see' Mercury above the northern hemisphere and southern hemisphere, respectively. An HGA of 80cm diameter is used for the high speed X-band. The average bit rate is 16 kbps, which in turn translates into ~40 Mbyte/day assuming a 6 h consecutive pass on average. 2.0 GByte volume is assumed for the data recorder for the storage of MMO housekeeping and science data before the transmission to the Earth.
MMO Sunshield and Interface Structure (MOSIF) surrounding the MMO and with closure MLI to MPO (after Fig 9., Benkhoff et al,. 2010).
As the MMO is a spinning spacecraft, it needs to be thermally protected during the interplanetary cruise phase - this is done by the MOSIF (figure above).
Taken from:
Benkoff, J., van Casteren, J. & Hayakawa, H. BepiColombo—Comprehensive exploration of Mercury: Mission overview and science goals. Planetary and Space Science 58, 2–20 (2010).
Kasaba, Y. et al. The Plasma Wave Investigation (PWI) onboard the BepiColombo/MMO: First measurement of electric fields, electromagnetic waves, and radio waves around Mercury. Planetary and Space Science 58, 238–278 (2010).
Mukai, T., Yamakawa, H., Hayakawa, H., Kasaba, Y. & Ogawa, H. Present status of the BepiColombo/Mercury magnetospheric orbiter. Advances in Space Research 38, 578–582 (2006).
Yamakawa, H., Ogawa, H., Sone, Y. & Hayakawa, H. BepiColombo Mercury magnetospheric orbiter design. Acta Astronautica (2008). doi:10.1016/j.actaastro.2008.01.040
Yoshikawa, I. et al. The Mercury sodium atmospheric spectral imager for the MMO spacecraft of Bepi-Colombo. Planetary and Space Science 58, 224–237 (2010).
Quelle: ESA
Update: 27.01.2016 


If ESA’s Mercury orbiter of the BepiColombo mission seems to stand at an unusual angle above its test chamber floor, that’s because it does – intentionally so.
The orbiter underwent ‘electromagnetic compatibility, radiated emission and susceptibility’ testing last month inside the Maxwell chamber of ESA’s ESTEC Test Centre in Noordwijk, the Netherlands.
Maxwell’s shielded metal walls and doors form a ‘Faraday cage’ to block unwanted external electromagnetic radiation, while its internal walls are cover with ‘anechoic’ radio-absorbing foam pyramids to mimic boundless space.
“We are performing two types of compatibility testing,” explained Marco Gaido, assembly, integration and test manager for BepiColombo.
“First, we are checking the craft is electrically compatible with the electrical field generated by the Ariane 5 launcher that will deliver it into orbit, with no possibility of interference with BepiColombo’s receivers.
“Secondly, we are testing if there is any risk of incompatibility between the different subsystems of the spacecraft itself when it orbits Mercury. In particular, we want to check that its trio of antennas on top can communicate properly with Earth.
“Accordingly, it was deliberately oriented to simulate a worst-case scenario for test purposes.”
The orbiter was positioned to allow deployment of its medium-gain antenna in terrestrial gravity. The high-gain antenna reflector meanwhile was deployed in a worst-case position, supported by a dedicated fixture.
The spacecraft was tilted by means of a large platform while the high-gain antenna was supported by a tower made of wood, transparent to radio waves. All test cables used were shielded to reduce potential interference.
ESA’s Mercury Planetary Orbiter will be launched to Mercury together with Japan’s Mercury Magnetospheric Orbiter aboard an ESA-built carrier spacecraft, the Mercury Transfer Module. This entire three-module BepiColombo stack will undergo similar testing at ESTEC.
Quelle: ESA
Update: 17.04.2017

BepiColombo at Mercury


New artist's views of the BepiColombo spacecraft that will be launched to Mercury in 2018
Quelle: ESA
Update: 5.07.2017
Quelle: ESA
Update: 6.07.2017

BepiColombo: Joint Mercury mission ready for 'pizza oven'

Stack on show
Image captionFully fuelled at launch, the 6.4m-high flight stack will weigh over four tonnes

The two satellites that make up the BepiColombo mission to Mercury were presented to the media on Thursday. 

This joint European-Japanese venture has been in development for nearly two decades, but should finally get to the launch pad in 15 months' time.

The two spacecraft will travel together to the baking world but separate on arrival to conduct their own studies.

Thursday's event in the Netherlands was the last chance for journalists to view the so-called "flight stack".

This is the edifice that goes on top of the rocket and comprises Europe's Mercury Planetary Orbiter (MPO) and Japan's Mercury Magnetospheric Orbiter (MMO), as well as the propulsion module to control their path towards the world that circles closest to the Sun.

As a single item, the stack has just finished a series of important tests, but it will shortly be taken apart so that the individual components can continue with their own preparations. The structure will not be reassembled until all equipment reaches the Kourou spaceport in French Guiana. 

The double mission is due to blast away from Earth on an Ariane rocket in October 2018. Everyone will have to be patient, however. It is going to take seven years for the satellite duo to get to their destination. 

The gravity of the Sun pulls hard on any spacecraft travelling into the inner Solar System, and Bepi will have to fire thrusters in the direction of travel to ensure it does not overshoot Mercury. 

"Mercury is the least explored of the rocky planets, but not because it is uninteresting," said Prof Alvaro Giménez Cañete, the director of science at the European Space Agency (Esa). 

"It's because it's difficult. It's difficult to get there; it's even more difficult to work there." 

Temperatures on the surface of the diminutive world go well above 400C - hot enough to melt some metals, such as tin, zinc and lead.

How to build a mission to Mercury

StackImage copyrightESA
Image captionEurope's Airbus company led production of the MTM, MPO and the sun shield for MMO
  • MTM is a propulsion module to control the cruise to Mercury
  • Europe's Mercury Planetary Orbiter carries 11 instruments
  • For the cruise phase, a sun shield protects the MMO
  • At Mercury, Japan's orbiter dispenses with the shield 
  • It will simply spin to prevent its surfaces from overheating
  • MMO and MPO will go into different polar orbits at Mercury

The MPO and MMO will be looking to deepen and extend the knowledge gained at Mercury by the US space agency’s recent Messenger mission. 

The American probe, which ceased operations in 2015, took some 270,000 images of the planet's surface and acquired 10 terabytes of other scientific measurements. 

It provided remarkable new insights on the composition and structure of the smallest terrestrial planet, and it made the amazing discovery that, despite those high temperatures, there are shadowed craters where it is still cold enough to support water-ice. 

Esa and the Japanese space agency (Jaxa) hope that the more advanced, higher-resolution technology on their satellites will be able to answer questions that Messenger could not. 

Esa's BepiColombo project scientist, Johannes Benkhoff, said: "We need to come up with new ideas. And for that reason we need to have good instrumentation and we need to do very close monitoring of the planet; and we can do that with our spacecraft that we're sending to Mercury."

The oddball close to the Sun

Media captionEmma Bunce: "Bepi will allow us to make a step change in our understanding"
  • Past Mercury visitors were Nasa missions: Mariner 10 and Messenger
  • The planet's diameter is 4,880km - about one-third that of the Earth
  • It is the second densest planet in the Solar System: 5.4 grams/cu cm
  • The Caloris Basin is the largest surface feature (1,550km across)
  • It is an extreme place: surface temps swing between 425C and -180C
  • There is water-ice in the planet's permanently shadowed craters
  • Mercury's huge iron core takes up more than 60% of the planet's mass
  • Apart from Earth, it is the only inner planet with a global magnetic field

The key conundrum is why the planet contains an outsized iron core and only a thin veneer of silicate rocks. 

A favoured theory before Messenger was that Mercury at some point in its history was stripped of its outer layers, either by a big collision with another body or by the erosive effects of being so close to the Sun. 

But the American probe observed large abundances of volatile substances. "They shouldn't be there had those events happened in Mercury's past; the sulphur and potassium volatiles on the surface just shouldn't be there," insisted Prof Emma Bunce, a principal investigating scientist from Leicester University, UK. 

"And the other mystery about the surface is that there isn't much iron on it, seemingly; and so that needs to be looked into in more detail and that's something we'll be able to do with our imaging X-ray spectrometer, MIXS."

Europe's MPO will have a total of 11 instruments onboard. It will fly in a near-circular polar orbit around the planet, mapping the terrain, generating height profiles, sensing the interior, and collecting data on surface composition and the wispy "atmosphere". 

Japan's MMO will have five instruments and will investigate the planet's magnetic field. 

Mercury is the only terrestrial planet - apart from Earth - to have a global magnetic field. But it is an odd one. The field is roughly three times stronger in the northern hemisphere than it is in the south. 

Media captionMessenger compiled this exaggerated colour map of Mercury during its first year in orbit

Both Esa and Jaxa are delighted to at last be approaching launch. 

The development of the mission, particularly on the European side, has been a torrid learning curve. 

The launch date was repeatedly put back as engineers struggled to find equipment that could cope with the intense heat and radiation experienced just a few tens of millions of km from the Sun. The development of solar cells in particular proved extremely problematic. 

"We're flying into a pizza oven," quipped Esa project manager Ulrich Reininghaus. "We had to test materials at different, very high temperature regimes, sometimes with very unwanted results." 

When Esa's Science Programme Committee originally green-lit BepiColombo in 2000, it had in mind a launch in 2009. Even when the industrial contract to build the MPO was finally signed in 2008, a launch was thought possible in 2013. 

Esa says the mission is costing roughly €1.65bn (£1.45bn; $1.85bn). This includes all European and Japanese costs.

One fascinating aside. That SPC meeting in 2000 also approved Esa participation in the successor space telescope to Hubble, which is called the James Webb Space Telescope. Its development schedule has also been heavily delayed and is itself now booked for launch on an Ariane in October 2018.

But it is not possible to put both missions up at the same time, so one will have to stand aside. A decision on whether it is Bepi or JWST that goes first is likely to be made this September.

Image copyrightNASA/JHU-APL/CIW
Image captionMessenger found hollowed out surface features that indicated the presence of volatiles

Quelle: BBC


Update: 7.07.2017


BepiColombo stack


ESA’s Mercury spacecraft has passed its final test in launch configuration, the last time it will be stacked like this before being reassembled at the launch site next year.

BepiColombo’s two orbiters, Japan’s Mercury Magnetospheric Orbiter and ESA’s Mercury Planetary Orbiter, will be carried together by the Mercury Transport Module. The carrier will use a combination of electric propulsion and multiple gravity-assists at Earth, Venus and Mercury to complete the 7.2 year journey to the Solar System’s mysterious innermost planet

BepiColombo’s journey to Mercury

Once at Mercury, the orbiters will separate and move into their own orbits to make complementary measurements of Mercury’s interior, surface, exosphere and magnetosphere. The information will tell us more about the origin and evolution of a planet close to its parent star, providing a better understanding of the overall evolution of our own Solar System.

To prepare for the harsh conditions close to the Sun, the spacecraft have undergone extensive testing both as separate units, and in the 6 m-high launch and cruise configuration.

One set of tests carried out earlier this year at ESA’s technical centre in the Netherlands focused on deploying the solar wings, and the mechanisms that lock each panel in place. The 7.5 m-long array of the Mercury Planetary Orbiter and the two 12 m-long array of the Mercury Transport Module will be folded while inside the Ariane 5 rocket.

BepiColombo vibration test

Last month, the full spacecraft stack was tested inside the acoustic chamber, where the walls are fitted with powerful speakers that reproduce the noise of launch.

Just last week, tests mimicked the intense vibrations experienced by a satellite during launch. The complete stack was shaken at a range of frequencies, both in up-down and side-to-side motions.

These were the final tests to be completed with BepiColombo in mechanical launch configuration, before it is reassembled again at the launch site.

Mercury Transfer Module solar wing deployment

In the coming weeks the assembly will be dismantled to prepare the transfer module for its last test in the thermal–vacuum chamber. This will check it will withstand the extremes of temperatures en route to Mercury.

The final ‘qualification and acceptance review’ of the mission is foreseen for early March. Then BepiColombo will be flown to Europe’s Spaceport in Kourou, French Guiana, in preparation for the October 2018 departure window. The date will be confirmed later this year.

“This week was the last opportunity to see the spacecraft in its stacked launch configuration before it leaves Europe. The next time will be when we are at the launch site already fueled,” says Ulrich Reininghaus, ESA’s BepiColombo Project Manager. “This is quite a milestone for the project team. We are looking forward to completing the final tests this year, and shipping to Kourou on schedule.”

Quelle: ESA


Tags: Raumfahrt ESA Merkur Mission BepiColombo 


Freitag, 7. Juli 2017 - 21:00 Uhr

Astronomie - XARM Röntgen-Astronomie-Teleskop als Ersatz für Hitomi



NASA and JAXA to develop replacement X-ray astronomy telescope


WASHINGTON — NASA and the Japanese space agency JAXA will start work this spring on an orbiting X-ray astronomy telescope to replace one lost shortly after launch last year.

In a presentation to the Committee on Astronomy and Astrophysics of the National Academies March 28, Paul Hertz, director of NASA’s astrophysics division, said a formal start of the project known as the X-Ray Astronomy Recovery Mission (XARM) will take place shortly after the start of the new Japanese fiscal year April 1.

“We are moving forward with the X-Ray Astronomy Recovery Mission,” Hertz said. The mission, he said, was included in the Japanese government’s budget for the new fiscal year, pending approval by the country’s parliament, the Diet.


XARM is intended to be a replacement for Hitomi, an X-ray astronomy spacecraft launched by JAXA in February 2016 but which malfunctioned in orbit a month and a half later. An investigation determined a chain of errors in the spacecraft’s attitude control system, compounded by human error, caused the spacecraft to spin up and its solar panels to break off, depriving the spacecraft of power.

NASA’s contribution to XARM will be the same as Hitomi, a soft X-ray spectrometer instrument, Hertz said. “Our deal is to provide the same hardware that we provided last time. We’re doing a built-to-print” version of the instrument, he said.

A formal review of NASA’s role on XARM, called Key Decision Point B, is planned for June. “We will then officially establish the XARM project,” he said.

He did not disclose the cost of XARM for NASA, but in a presentation last summer suggested rebuilding the instrument would cost between $70 and 90 million, spread out from 2017 to 2021. That cost, he said then, could be accommodated with existing planned budgets for NASA’s astrophysics division without doing “grievous harm” to other programs.

One issue to be worked out with JAXA, Hertz indicated, is the data release policy for XARM. He said he considered it to be a “directed” mission, which would make data from the instrument immediately available to astronomers. This is in contrast to “competed” missions led by a principal investigator, who has an initial proprietary period to analyze the data before it is widely released. That approach is still being negotiated with the Japanese, he said.

Previous versions of the NASA-built X-ray spectrometer instrument flew on two previous JAXA spacecraft, one lost in a 2000 launch failure and another that suffered a helium leak shortly after a 2005 launch that prevented the instrument from working. Hertz, in his presentation, pronounced XARM as “charm.” “It does need some luck,” he said.

Quelle: SN


Update: 7.07.2017


JAXA, NASA approve replacement for failed Hitomi astronomy satellite

Artist’s concept of the failed Hitomi satellite. Credit: JAXA

The Japanese space agency is moving ahead with a smaller-scale X-ray astronomy satellite to replace the failed Hitomi observatory, which spun out of control about a month-and-a-half after its launch last year.

The X-ray Astronomy Recovery Mission, or XARM, could launch as soon as March 2021, filling a potential gap in astronomers’ X-ray vision of the universe, according to the Japan Aerospace Exploration Agency, or JAXA.

NASA has agreed to a junior partner in XARM — pronounced “charm” — and supply X-ray telescopes and a spectrometer instrument for the Japanese-led mission, according to Paul Hertz, directory of NASA’s astrophysics division.

The Japanese Diet approved spending on XARM for the Japanese government’s current fiscal year, which started in April, and officials are in the final stages of formally kicking off development of the mission, Hertz said in a recent interview with Spaceflight Now.

The Hitomi satellite failed in March 2016 after a series of attitude control problems caused the orbiting observatory to spin up and shed segments of its power-generating solar panels. Ground controllers lost contact with the satellite as it orbited more than 350 miles (575 kilometers) above Earth.

Astronomers viewed the roughly $400 million mission as a stepping stone between current flagship-class X-ray telescopes, like NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM-Newton, and an upgraded, more sensitive X-ray observatory called Athena due for launch in the late 2020s.

Hertz said XARM will not have the observing range of Hitomi, which carried four scientific instruments sensitive to a range of X-ray wavelengths and gamma-rays, exposing astronomers to the workings of some of the most extreme events and environments in the cosmos, such as black holes, neutron stars and the creation of galaxies in the distant, ancient universe.

XARM will instead carry replacements for Hitomi’s two lower-energy instruments — the Soft X-ray Imager and the Soft X-ray Spectrometer. Both instruments contain critical parts provided by NASA, and the spectrometer is primarily a U.S.-developed payload.

“The mission will not be a carbon copy (of Hitomi), but the NASA contribution will be a carbon copy,” Hertz said in an interview. “The XARM mission is going to have only two of the four instruments that Hitomi had. It will have the Soft X-ray Spectrometer and the Soft X-ray Imager. The latter is a JAXA instrument, but we provided the telescope for both of those.”

XARM will not need an extendable 20-foot (6-meter) boom like Hitomi, Hertz said, because it will fly without the hard X-ray instruments that needed the deployable arm. Hard X-rays are at the higher-energy, shorter-wavelength end of the spectrum of X-ray light.

“That makes it a simpler mission, so although our part will be built-to-print, there will obviously be some changes on the bus,” Hertz said.

The Soft X-ray Imager on XARM will also have improved resolution over the instrument on Hitomi, JAXA officials said.

JAXA managers said NASA’s NuSTAR telescope, which sees the universe in hard X-rays, could fill in for the missing high-energy instruments on XARM. The two observatories could conduct coordinated, tandem observations to help realize Hitomi’s original science objectives.

NASA will spend between $70 million and $90 million on its part of the XARM observatory, according to Hertz. Flight spares at NASA’s Goddard Space Flight Center from the original Hitomi development will help save some money, he said.

The European Space Agency is also a minor partner in Hitomi’s replacement mission.

A Japanese government document dated May 30 indicated JAXA would set up a project team and select a manufacturer for the XARM spacecraft within one year.

Quelle: SN

Tags: Astronomie - XARM Röntgen-Astronomie-Teleskop als Ersatz für Hitomi 


Freitag, 7. Juli 2017 - 20:45 Uhr

Raumfahrt - China plant Meer-Starts für kommerzielle Nutzlasten


China develops sea launches to boost space commerce

BEIJING, China has a clear plan to provide sea launches for commercial payloads to be carried by Long March rockets, according to an aerospace official.
Tang Yagang, vice head of the aerospace division of the No.1 institute of the China Aerospace Science and Technology Corporation (CASTC), said that the technology is not difficult and a sea launch platform can be built based on modifying 10,000-tonne freighters.
China will use solid carrier rockets which rely less on launch facilities and feature mature technology, Tang said, adding that key technology for the carrier rockets will be tested at sea this year and the service is expected to be available for international users in 2018.
At that time, Long March launch vehicles will be able to send satellites weighing 500 kilograms to a 500-kilometer-high sun-synchronous orbit with an inclination of zero to ten degrees, Tang said.
Countries in the equator region have growing needs for launching near-equatorial and low-inclination satellites, said Fu Zhiheng, deputy general manager of China Great Wall Industry Corporation, affiliated to the CASTC.
"The closer to the equator we launch a satellite, the less carrying capacity it will lose, and the lower the cost will be," Fu said, adding that space powers are competing to develop near-equatorial sea launches.
Currently, Long March carrier rockets have provided 60 commercial launches for domestic and international users, Fu said.

Quelle: Xinhua

Tags: Raumfahrt - China plant Meer-Starts für kommerzielle Nutzlasten 


Freitag, 7. Juli 2017 - 07:59 Uhr

Raumfahrt - XCOR Aerospace Lynx Suborbital Vehicle - Update-2


XCOR Aerospace lays off all employees, throwing rocket projects into limbo

XCOR Aerospace had to put work on the Lynx suborbital space plane on hold. (XCOR Illustration)


After more than a year’s worth of workforce shrinkage, XCOR Aerospace has laid off the remainder of its employees – putting projects ranging from its Lynx suborbital space plane to its work on rocket propulsion systems into deep limbo.

Word of the layoffs came via Parabolic Arc’s Douglas Messier on Wednesday, and was confirmed by the Midland Reporter-Telegram in Texas.

XCOR is based in Midland, although it also had employees at the Mojave Air and Space Port in California.

The job cuts began last year when XCOR let go of 25 employees, about 50 percent of its workforce, and decided to focus on propulsion system development rather than the Lynx rocket plane. XCOR extended the layoffs last week.

“Due to adverse financial conditions XCOR had to terminate all employees as of 30 June 2017,” the company said in a statement provided to Parabolic Arc as well as Space News.

XCOR said some employees would be brought back on as contractors to maintain the company’s intellectual property and explore other options to get the company up and running again.



The company set up operations in Texas starting in 2012 to capitalize on $10 million in potential incentives from the Midland Development Corp. The Reporter-Telegram quoted Brent Hilliard, board chairman for the development group, as saying the layoffs and its impact on the incentive deal would be the subject of discussions with XCOR’s executives.

Three of XCOR’s co-founders left the company in 2015 to found a new space venturecalled Agile Aero. The executive who took over as XCOR’s president and CEO, Jay Gibson, left the company last month when the White House nominated him for the post of deputy chief management officer at the Defense Department.

XCOR’s two-seat Lynx rocket plane was once seen as a competitor for Virgin Galactic’s SpaceShipTwo and Blue Origin’s New Shepard in the suborbital spaceflight market.

The company suspended work on the Lynx following last year’s round of job cuts, and concentrated instead on its rocket propulsion work for United Launch Alliance.

XCOR’s hydrogen-fueled 8H21 engine was competing with Blue Origin’s BE-3 engine and Aerojet Rocketdyne’s enhanced RL-10 engine for use on United Launch Alliance’s ACES upper stage, which is destined to be added to ULA’s next-generation Vulcan rocket in the 2020s.

Quelle: GeekWire


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