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Sonntag, 22. Juni 2014 - 15:05 Uhr

UFO-Forschung - Projekt Blue Book - Teil-3

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The 701 Club
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Case # 9053
According to the NICAP web site the case is described as:
Aug. 18, 1964; Atlantic Ocean, 200 miles east of Dover, Delaware. 12:35 a.m. Witnesses: Maj. D.W. Thompson and First Pilot 1st Lt. J.F. Jonke, on a USAF C-124 transport plane. One round, blurred, reddish-white object was on a collision course with the C-124 from ahead and below. The airplane evaded the object. Sighting lasted 2 minutes.1
The Blue Book file only contains three pages of message traffic describing the event and a brief mention by Hynek to Quintanilla. The C-124 was flying at a magnetic heading of 260 and a TAS of 200 kts. They changed heading from 260 to 340. The time is listed as 0535Z and the sighting lasted 2 minutes.
1st Lt David Ross was the investigating officer and he reported the crew had another trip 15 hours after they had landed. He talked only to the aircraft commander and could not explain the event. There was no radar contact with the object and there were no aircraft in the area.
It seems that this was a very good unidentified case but I think that certain parts of the case were ignored.
Hynek’s investigation
Hynek really did not do much in the way of investigating this case. He proposed a possible solution but wanted to talk to the crew before labeling it identified:
Apparently these people were between two cloud decks and saw an object approaching them. It might have been a relatively stationary balloon which they were overtaking and passed. Since everything over the Atlantic is carefully checked by radar, this is a puzzler, and it would be very interesting to get the comments of the individual crew members. I would like to find out how bright the object appeared and also whether they ever saw it to the rear of the plane.2
It is not clear if Hynek ever talked to the crew because there are no other comments by Hynek in the files. However, he did include it in his book, “The UFO Experience” as a nocturnal light (listed as NL-10). It seems that all Hynek did was record it for his own records and did not bother to investigate much further than that because there is something missed or not mentioned by the investigation on this case.
A reasonable explanation
The first thing to determine was the plane’s position and direction to see if there might be a possible solution that could be checked. According to the file, the plane was 200 miles east of Dover, Delaware (no longitude/latitude was given). The plane was flying on a magnetic bearing of 260 degrees. The magnetic declination for this area is roughly -13 degrees, which means the true heading was 247 degrees.
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This sighting line is very interesting. Using Google Earth, this direction points towards the launch pads at Wallops Island, which is located about 220 miles away along a true bearing of 246 degrees. Was there activity at Wallops island that night?
The astronautix web site gives the following entry for the date in question:
1964 August 18 - . 06:05 GMT - . Launch Site: Wallops Island. Launch Complex: Wallops Island LA3. LV Family: Scout. Launch Vehicle: Scout X-4A. LV Configuration: Scout X-4A S129R. •Reentry 4A - . Nation: USA. Agency: NASA. Apogee: 183 km (113 mi). Summary: Scout launch tested Apollo-type ablator materials at lunar reentry heating levels.3
The rocket would have appeared to be a bright reddish ball of fire that would rise out of the lower cloud deck and move down range. The pilot stated he took an evasive turn to 340 degrees magnetic and reported that the UFO then took a right turn and disappeared. This “right turn” by the UFO could imply it went to the pilot’s left (not to his right), which is a reasonable description of the rocket’s trajectory towards the east. The duration of the first stage burn was about 40 seconds but the entire rocket burn (all four stages) was over two minutes. At this point, it seems possible that the Scout X-4A launch is a reasonable explanation.
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Possible reasons for rejection
Ican think of several factors that might give reason to reject this explanation. However, I do not think any of them are fatal. They are:
1. The difference in the time. There is a 30 minute difference between the time of the sighting and the time of rocket launch.
2. Clouds may have obscured the launch.
I don’t consider the clouds issue a serious problem because they were listed as broken. There could have been a clear area in the direction of the rocket launch. However, the time difference is a problem. We don’t really know if the time listed for the sighting is accurate. The investigating officer stated he only had time to interview the pilot. It may be possible that the time was approximate or recorded in error.
Why didn’t Blue Book identify it?
If you believe what UFOlogists state about Blue Book, they would have jumped at the chance in identifying this as a Scout X-4A launch. The lack of any mention of the rocket launch by the investigating officer, Hynek, or Blue Book staff indicates to me that nobody bothered to check for activity at Wallops Island. The staff at Blue Book seems to have left it up to the investigating officer to identify it and he chose only to interview the pilot. Complacency seems to be why this explanation was probably ignored.
Case closed?
In my opinion, this is a reasonable explanation for the event in question. The coincidence that the plane was pointed towards Wallops Island when they saw the UFO and that a rocket launch occurred within 30 minutes of the time of the sighting, is difficult to ignore. If we assume there is an error in the time of the event, then this can be listed as a probable rocket launch and remove it from the “unidentified list”.
Quelle: SUNlite 1/2013

Tags: UFO-Forschung 

2370 Views

Sonntag, 22. Juni 2014 - 14:49 Uhr

UFO-Forschung - Unzureichende Informationen in NICAP-Dokument als UFO-Beweis -TEIL 2

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March 9, 1957
The NICAP document lists the sighting in the chronology as:
March 9, 1957--Nr. San Juan, Puerto Rico. Pan American Airways pilot took evasive action as fiery round, greenish-white object passed plane. [V]1Reading Section V, we find the following description:
Round greenish-white object came toward airliner; outer ring appeared to reflect light from center; pilot took violent evasive action.2
That is pretty much it but there is a lot more about this case in the news reports of the day as well as the Blue Book file.
The details
According to NICAP the event occurred at 3:33 AM but the Blue Book documents stated there were two different events. One occurred at 0140 EST, while the main event was after 3:00 AM. While they lump them together, I consider them two separate incidents and will only address the 3:30 AM EST event, which is what the pilot reported.
What transpired that morning was best stated by the pilot, Captain Matthew Van Winkle. His story appeared in many newspapers on March 11, 1957. According to his account, the plane was on autopilot when he saw a bright object that appeared like a “big spotlight” approaching the plane. Van Winkle first thought it was an interceptor jet but then realized they travel in pairs. He took prompt action to avoid the approaching object and, as a result, several passengers were injured. According to Van Winkle, the ob- ject passed under the wing of his airplane. He also noted that it could not be a meteor because he had seen hundreds of them and they always come from above and head downward (a common misconception - meteors can go in any direction of the sky). In the same article, he noted that Captain Perry, who was the captain of a flight 175 miles behind him also saw the UFO at the same time he did. Perry described it as a “magnesium flash” that lasted about five seconds. Another pilot stated it had broken in two.
A general summary of the event is that a bright object had appeared out of the sky and flashed by the airplane in a brief period of time that was measured in seconds. It was visible over a wide area, which could be measured in hundreds of miles, and was very bright to all who saw it.
NICAP vs Blue Book
The Blue Book file is quite extensive with collections of various news paper clippings and UFO articles on the case. There was also many requests to various commands, including the Navy, wondering if it may have been a wayward missile or rocket of some kind. All responses were negative to these requests. Contrary to what NICAP proclaimed, there seemed to be an honest effort to look into all the possibilities. The file also includes copies of the report made by the Civil Aeronautics Board (CAB).
The CAB had statements from all the other air crews. It is interesting to note that Captain Wyland, who was about 113 miles to the ESE, also thought about taking evasive action indicating that he thought the object was close to him as well. Most of the observa- tions of the UFO were inside a radius of about 200 miles from Van Winkle’s plane. All described the duration as about five seconds or less. The CAB report also made mention of negative reports regarding any military activities. Probably the strangest comment was the following:
A CAB check of U.S. Weather Bureau and astronomical agencies in the area involved indicated no meteor activity at the time of the inci- dent3
This is an odd statement considering the planes were over the open ocean over 300 miles from land. It is unlikely that any astrono- mers were in the area unless they were on a plane or ship. They probably asked some observatories if any meteor showers were active on the night in question and received the answer of no. However, bright meteors can happen at any time and many famous fireball meteors are not even associated with a meteor shower. Meteor showers are usually associated with fine dust left behind by comets. While this can produce bright fireballs, they usually do not produce the kind that break up into small pieces or produce meteorites.
Blue Book concluded that this was a bright fireball despite this statement by the CAB. The evidence seems to be very good for this conclusion. It was seen over a large area, it lasted only a few seconds, and was very bright to all observers. Had it been a craft of some kind, the object would not have been visible to observers si- multaneously over a large area and its brightness would change with distance from the source. A fireball matches the description given by the air crews.
As is common in these cases, the pilots often proclaim what they saw could not be a meteor because they see them all the time. However, fireballs are unique in that they are very brilliant, appear to be closer than normal meteors, and can be quite startling. Observers frequently feel the meteor disappeared just beyond the treeline and was only a few hundred feet off the ground. This misperception is well documented.
On page 16 of the July 1957 UFO investigator (see image to right), NICAP argued about the meteor fireball explanation offered by Blue book.4 They used the state- ments by the Civil Aeronautics Board that they have yet to agree with this conclu- sion as evidence that this explanation was unacceptable. NICAP also stated that they did not rule out the possibility that it could have been a meteor but then spent a great deal of time trying to rationalize why this could not be a meteor. In one in- stance, they describe the event from two hours previously and state that the odds of two bright meteors being visible in the same area was too high. Another argu- ment was Van Winkle’s statement that the UFO was below the horizon. Of course, this ignores the possibility that Van Winkle was too busy trying to gain control of his aircraft after performing an evasive maneuver to make such an accurate observa- tion or that he might have been mistaken.
Another one bites the dust?
This case’s inclusion in “The UFO evidence” was more of a case of blindly disputing Blue Book’s conclusion regarding the sight- ing than a careful evaluation of the evidence. Looking at the sighting objectively, it appears that this was nothing more than a bright fireball. While one can not conclusively prove this was a fireball since it happened out to sea and can not be confirmed by ground observers, it is the most likely solution to the case. It should never have been considered to be evidence of UFOs that are “manifestations of extraterrestrial life”.
Quelle: SUNlite 1/2013

2289 Views

Sonntag, 22. Juni 2014 - 11:40 Uhr

Raumfahrt - Titan im Focus von Cassini

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Candle in the Dark
Saturn's rings cut across an eerie scene that is ruled by Titan's luminous crescent and globe-encircling haze, broken by the small moon Enceladus, whose icy jets are dimly visible at its south pole. North is up. 
The scattered light around planet-sized Titan (5,150 kilometers, or 3,200 miles across) makes the moon's solid surface visible in silhouette. Enceladus (505 kilometers, or 314 miles across) enjoys far clearer skies than its giant sibling moon. 
This view shows the unlit side of Saturn's rings. 
The image was taken in visible red light with the Cassini spacecraft narrow-angle camera on June 10, 2006 at a distance of approximately 3.9 million kilometers (2.4 million miles) from Enceladus and 5.3 million kilometers (3.3 million miles) from Titan. The view was obtained at a Sun-moon-spacecraft, or phase, angle of about 160 degrees relative to both moons. Image scale is 23 kilometers (15 miles) per pixel on Enceladus and 32 kilometers (20 miles) on Titan. 
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A Tale of Two Moons
Many denizens of the Saturn system wear a uniformly gray mantle of darkened ice, but not these two moons. The brightest body in the solar system, Enceladus, is contrasted here against Titan's smoggy, golden murk. 
Ironically, what these two moons hold in common gives rise to their stark contrasting colors. Both bodies are, to varying degrees, geologically active. For Enceladus, its southern polar vents emit a spray of icy particles that coats the small moon, giving it a clean, white veneer. On Titan, yet undefined processes are supplying the atmosphere with methane and other chemicals that are broken down by sunlight. These chemicals are creating the thick yellow-orange haze that is spread through the atmosphere and, over geologic time, falls and coats the surface. 
The thin, bluish haze along Titan's limb is caused when sunlight is scattered by haze particles roughly the same size as the wavelength of blue light, or around 400 nanometers. 
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were obtained on Feb. 5, 2006, using the Cassini spacecraft narrow-angle camera at a distance of 4.1 million kilometers (2.5 million miles) from Enceladus and 5.3 million kilometers (3.3 miles) from Titan. Resolution in the original images was 25 kilometers (16 miles) per pixel on Enceladus and 32 kilometers (20 miles) per pixel on Titan. The view has been magnified by a factor of two. 
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Hovering Over Titan
A mosaic of nine processed images recently acquired during Cassini's first very close flyby of Saturn's moon Titan on Oct. 26, 2004, constitutes the most detailed full-disc view of the mysterious moon. 
The view is centered on 15 degrees South latitude, and 156 degrees West longitude. Brightness variations across the surface and bright clouds near the south pole are easily seen. 
The images that comprise the mosaic have been processed to reduce the effects of the atmosphere and to sharpen surface features. The mosaic has been trimmed to show only the illuminated surface and not the atmosphere above the edge of the moon. The Sun was behind Cassini so nearly the full disc is illuminated. Pixels scales of the composite images vary from 2 to 4 kilometers per pixel (1.2 to 2.5 miles per pixel). 
Surface features are best seen near the center of the disc, where the spacecraft is looking directly downwards; the contrast becomes progressively lower and surface features become fuzzier towards the outside, where the spacecraft is peering through haze, a circumstance that washes out surface features. 
The brighter region on the right side and equatorial region is named Xanadu Regio. Scientists are actively debating what processes may have created the bizarre surface brightness patterns seen here. The images hint at a young surface with, no obvious craters. However, the exact nature of that activity, whether tectonic, wind-blown, fluvial, marine, or volcanic is still to be determined. 
The images comprising this mosaic were acquired from distances ranging from 650,000 kilometers (400,000 miles) to 300,000 kilometers (200,000 miles). 
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Composite of Titan's Surface Seen During Descent
This composite was produced from images returned yesterday, January 14, 2005, by the European Space Agency's Huygens probe during its successful descent to land on Titan. It shows a full 360-degree view around Huygens. The left-hand side, behind Huygens, shows a boundary between light and dark areas. The white streaks seen near this boundary could be ground 'fog,' as they were not immediately visible from higher altitudes. 
As the probe descended, it drifted over a plateau (center of image) and was heading towards its landing site in a dark area (right). From the drift of the probe, the wind speed has been estimated at around 6-7 kilometers (about 4 miles) per hour. 
These images were taken from an altitude of about 8 kilometers (about 5 miles) with aresolution of about 20 meters (about 65 feet) per pixel. The images were taken by the Descent Imager/Spectral Radiometer, one of two NASA instruments on the probe. 
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Titan Descent
This picture is a composite of 30 images from ESA's Huygens probe. They were taken from an altitude varying from 13 kilometers down to 8 kilometers when the probe was descending towards its landing site. 
The images have a resolution of about 20 meters per pixel and cover an area extending out to 30 kilometers. 
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Liquid Lakes on Titan
The existence of oceans or lakes of liquid methane on Saturn's moon Titan was predicted more than 20 years ago. But with a dense haze preventing a closer look it has not been possible to confirm their presence. Until the Cassini flyby of July 22, 2006, that is. 
Radar imaging data from the flyby, published this week in the journal Nature, provide convincing evidence for large bodies of liquid. This image, used on the journal's cover, gives a taste of what Cassini saw. Intensity in this colorized image is proportional to how much radar brightness is returned, or more specifically, the logarithm of the radar backscatter cross-section. The colors are not a representation of what the human eye would see. 
The lakes, darker than the surrounding terrain, are emphasized here by tinting regions of low backscatter in blue. Radar-brighter regions are shown in tan. The strip of radar imagery is foreshortened to simulate an oblique view of the highest latitude region, seen from a point to its west. 
This radar image was acquired by the Cassini radar instrument in synthetic aperture mode on July 22, 2006. The image is centered near 80 degrees north, 35 degrees west and is about 140 kilometers (84 miles) across. Smallest details in this image are about 500 meters (1,640 feet) across. 
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Mapping Titan's Changes
The three mosaics shown here were composed with data from Cassini's visual and infrared mapping spectrometer taken during the last three Titan flybys, on Oct. 28, 2005 (left image), Dec. 26, 2005 (middle image), and Jan. 15, 2006 (right image). 
These false-color images were constructed from images taken at the following wavelengths: 1.6 microns (blue), 2.01 (green), and 5 microns (red). 
The viewing geometry of the December flyby is roughly on Titan's opposite hemisphere from the flybys in October and January. There are several important features to note in the images. The first is that the south polar cloud system was very bright during the December flyby, while during the October and January flybys, it is barely visible, indicating that the atmosphere over Titan's south pole is very dynamic. 
In the December (middle) mosaic, a north polar hood that is bright at 5 microns is visible. Its composition is unknown. The north polar hood is barely seen in the October (left image) and January (right image) data. Visible in the October and January images just south of the equator is Tui Reggio, a region nicknamed the "chevron." This region is very bright at 5 microns and is among the brightest features on Titan at that wavelength. Tui Reggio is thought to be a surface deposit, probably of volcanic origin, and may be water and/or carbon dioxide frozen from the vapor. The January flyby data show that the western margins of Tui Reggio have a complex flow-like character consistent with eruptive phenomena.
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First Color View of Titan's Surface
This image was returned yesterday, January 14, 2005, by the European Space Agency's Huygens probe during its successful descent to land on Titan. This is the colored view, following processing to add reflection spectra data, and gives a better indication of the actual color of the surface. 
Initially thought to be rocks or ice blocks, they are more pebble-sized. The two rock-like objects just below the middle of the image are about 15 centimeters (about 6 inches) (left) and 4 centimeters (about 1.5 inches) (center) across respectively, at a distance of about 85 centimeters (about 33 inches) from Huygens. The surface is darker than originally expected, consisting of a mixture of water and hydrocarbon ice. There is also evidence of erosion at the base of these objects, indicating possible fluvial activity. 
The image was taken with the Descent Imager/Spectral Radiometer, one of two NASA instruments on the probe. 
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Flyover of Sotra Facula, Titan
This image is based on data from NASA's Cassini spacecraft and shows a flyover of an area of Saturn's moon Titan known as Sotra Facula. Scientists believe Sotra is the best case for an ice volcano -- or cryovolcano -- region on Titan. The flyover shows two peaks more than 1,000 meters (3,000 feet) tall and multiple craters as deep as 1,500 meters (5,000 feet). It also shows finger-like flows. All of these are land features that indicate cryovolcanism. The 3-D topography comes from Cassini's radar instrument. Topography has been vertically exaggerated by a factor of 10. The false color in the initial frames shows different compositions of surface material as detected by Cassini's visual and infrared mapping spectrometer. In this color scheme, dunes tend to look relatively brown-blue. Blue suggests the presence of some exposed ice. Scientists think the bright areas have an organic coating that hides the ice and is different and lighter than the dunes. The finger-like flows appear bright yellowish-white, like the mountain and caldera. The second set of colors shows elevation, with blue being lowest and yellow and white being the highest. Dunes here appear blue because they tend to occupy low areas. The finger-like flows are harder to see in the elevation data, indicating that they are thin, maybe less than about 100 meters (300 feet) thick. 
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Clouds Clearing around Titan's North Pole
This pair of false-color images, made from data obtained by NASA's Cassini spacecraft, shows clouds covering parts of Saturn's moon Titan in yellow. Based on the way near-infrared channels of light were color-coded, cloud cover appears yellow, while Titan's hazy atmosphere appears magenta. The images show cloud cover dissolving from Titan's north polar region between May 12, 2008 (left), and Dec. 12, 2009 (right). The clouds in the second image appear around 40 degrees south latitude, still active late after Titan's equinox. 
Cassini's first observations of clouds near this latitude occurred during summer in the southern hemisphere. Equinox, when the sun shone directly over the equator, occurred in August 2009. It brought a changing of the seasons, as Titan moved out of southern summer into northern spring. 
For the past six years, Cassini has observed clouds clustered in three distinct latitude regions of Titan: large clouds at the north pole, patchy cloud at the south pole and a narrow belt around 40 degrees south. Now scientists are seeing evidence of seasonal circulation turnover at Titan. Clouds at the south pole disappeared just before equinox and the clouds in the north are thinning out. This activity agrees with models that predict cloud activity reversing from one hemisphere to another. 
During winter in the northern hemisphere, northern polar clouds of ethane formed in Titan's troposphere, the lowest part of the atmosphere, from a constant influx of ethane and aerosols from a higher part of the atmosphere known as the stratosphere. In the southern hemisphere, atmospheric gases enriched with methane welled up from the surface to produce mid- and high-latitude clouds. 
The data for the images was detected by Cassini's visual and infrared mapping spectrometer in near-infrared wavelengths. Scientists focused on three wavelengths of infrared radiation that were particularly good for observing cloud signatures and assigned them red, green and blue channels. Emissions in the 2 micron wavelength of light, colored red, detect the Titan surface. Emissions in the 2.11 micron wavelength, colored green, detect the lowest part of the Titan atmosphere, or troposphere. Emissions at the 2.21 micron wavelength, colored blue, detect the hazy stratosphere, a higher part of the atmosphere. The clouds appear yellowish because they lit up the channels designated red and green, but not the blue channel. 
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'Black Cat' on Titan
This radar image of the surface of Saturn's moon Titan was acquired on October 26, 2004, when the Cassini spacecraft flew approximately 1,600 kilometers (994 miles) above the surface and acquired radar data for the first time. 
Brighter areas may correspond to rougher terrains and darker areas are thought to be smoother. This image highlights some of the darker terrain, which the Cassiniteam has dubbed "Si-Si the Cat." This nickname was chosen after a team member'sdaughter, Si-Si, pointed out that the dark terrain has a cat-like appearance. Theinterconnected dark spots are consistent with a very smooth or highly absorbingsolid, or could conceivably be liquid. 
The image is about 250 kilometers (155 miles) wide by 478 kilometers (297 miles) long, and is centered at 50 N, 54 W in the northern hemisphere of Titan, over a region that has not yet been imaged optically. The smallest details seen on the image vary from about 300 meters (984 feet) to 1 kilometer (.62 mile). 
The data were acquired in the synthetic aperture radar mode of Cassini's radar instrument. In this mode, radio signals are bounced off the surface of Titan. 
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Neutral Gas Cloud Around Titan
Images from the magnetospheric imaging instrument and the ion and neutral camera onboard the Cassini spacecraft reveal aspects of the interactions between Saturn's dynamic population of hot energetic ions and the clouds of cold neutral atoms. Future observations may further explain the relationships between these interactions. 
The most recent image of Titan reveals the emission of high-speed neutral atoms from a globular region approximately 70,000 kilometers (43,496 miles) in diameter, clearly centered on Titan. It is only 1/25 as bright as the region seen toward dawn during Saturn orbit insertion, even though Cassini is now closer to Titan. There is an extended emission region around the Titan cloud, but it is much dimmer than the Titan cloud itself and even dimmer compared to the emission seen in the dawn direction at orbit insertion. In this image, the X marks the direction toward the Sun; the Y marks the direction toward Saturn's dawn; and the Z marks Saturn's rotation axis. The dot in the center marks Titan. 
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Titan's North Polar Region
This Cassini false-color mosaic shows all synthetic-aperture radar images to date of Titan's north polar region. Approximately 60 percent of Titan's north polar region, above 60 degrees north latitude, is now mapped with radar. About 14 percent of the mapped region is covered by what is interpreted as liquid hydrocarbon lakes. 
Features thought to be liquid are shown in blue and black, and the areas likely to be solid surface are tinted brown. The terrain in the upper left of this mosaic is imaged at lower resolution than the remainder of the image 
Most of the many lakes and seas seen so far are contained in this image, including the largest known body of liquid on Titan. These seas are most likely filled with liquid ethane, methane and dissolved nitrogen. 
Many bays, islands and presumed tributary networks are associated with the seas. The large feature in the upper right center of this image is at least 100,000 square kilometers (40,000 square miles) in area, greater in extent than Lake Superior (82,000 square kilometers or 32,000 square miles), one of Earth's largest lakes. This Titan feature covers a greater fraction of the surface, at least 0.12 percent, than the Black Sea, Earth's largest terrestrial inland sea, at 0.085 percent. Larger seas may exist, as it is probable that some of these bodies are connected, either in areas unmapped by radar or under the surface (see PIA08365). 
Of the 400 observed lakes and seas, 70 percent of their area is taken up by large "seas" greater than 26,000 square kilometers (10,000 square miles). 
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Exploring the Wetlands of Titan
Cassini peers through the murky orange haze of Titan to spy what are believed to be bodies of liquid hydrocarbons, two of them as large as seas on Earth, near the moon's north pole. 
This movie blends a near natural-color view and an infrared glimpse of Titan's surface obtained by the visual cameras, followed by a transition to imagery collected by the radar instrument aboard Cassini, for a dramatic reveal of the north pole of Saturn's largest moon. As the movie zooms in on the north pole, the most readily visible bodies are outlined in blue. The largest of these, on the left, is as big as the Caspian Sea on Earth; the next largest, on the right, is about the size of Lake Superior. When compared to the surface area of Titan however (which is six times smaller than Earth's), these bodies are equivalent in size to the Bay of Bengal and Timor Sea, respectively. Geographically speaking, they are more like seas.
The movie continues with a gradual transition to a polar map of the radar imagery taken so far by Cassini of the north polar region. It is clear that one of the radar swaths has intersected a small upper bay of the largest sea, and has almost entirely imaged the second one. 
The extreme darkness of these regions in the radar data argues strongly for the presence of liquid hydrocarbons, such as methane and ethane, which remain liquid at Titan's frigid temperature of minus 180 degrees Celsius (minus 288 degrees Fahrenheit). 
The movie continues with a pan across the pole and the radar imagery that has uncovered a multitude of much smaller lakes. 
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Mercator Projection of Huygens's View at Different Altitudes
This poster shows a flattened (Mercator) projection of the view from the descent imager/spectral radiometer on the European Space Agency's Huygens probe at four different altitudes. The images were taken on Jan. 14, 2005. 
The Huygens probe was delivered to Saturn's moon Titan by the Cassini spacecraft, which is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif. NASA supplied two instruments on the probe, the descent imager/spectral radiometer and the gas chromatograph mass spectrometer.
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Mosaic of River Channel and Ridge Area on Titan
This mosaic of three frames from the Huygens Descent Imager/ Spectral Radiometer (DISR) instrument provides unprecedented detail of the high ridge area including the flow down into a major river channel from different sources. 
The Descent Imager/Spectral Radiometer is one of two NASA instruments on the probe. 
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Purple Haze
Encircled in purple stratospheric haze, Titan appears as a softly glowing sphere in this colorized image taken one day after Cassini’s first flyby of the moon on July 2, 2004. 
This image shows a thin, detached haze layer that appears to float above the main atmospheric haze. Because of its thinness, the high haze layer is best seen at the moon’s limb. NASA's Voyager spacecraft detected such detached haze layers on Titan during their flybys in the early 1980s. 
The image, which shows Titan's southern polar region, was taken using a spectral filter sensitive to wavelengths of ultraviolet light centered at 338 nanometers. The image has been false-colored to approximate what the human eye might see were our vision able to extend into the ultraviolet: The globe of Titan retains the pale orange hue our eyes usually see, and both the main atmospheric haze and the thin detached layer have been given their natural purple color. The haze layers have been brightened for visibility. 
The best possible observations of the detached layer are made in ultraviolet light because the small haze particles which populate this part of Titan's upper atmosphere scatter short wavelengths more efficiently than longer visible or infrared wavelengths. This accounts for the bluish-purple color. 
Images like this one reveal some of the key steps in the formation and evolution of Titan's haze. The process begins in the high atmosphere (at altitudes higher than 600 kilometers or 370 miles), where solar ultraviolet light breaks down methane and nitrogen molecules. The products react to form more complex organic molecules containing carbon, hydrogen and nitrogen, and these in turn combine to form the very small particles seen as high hazes. The small particles stick upon collision with one another, forming larger particles which fall deeper into the atmosphere to maintain the lower main haze layer which is thick enough to obscure the surface at visible wavelengths. The altitude of the detached haze layer observed by Cassini (near 500 kilometers or 310 miles) is significantly higher than the detached haze seen by Voyager (at 300 to 350 kilometers or 185 to 215 miles). The upward shift in haze altitude from Voyager to Cassini suggests the possibility of seasonality in haze production or atmospheric circulation strength. The image was taken with the Cassini spacecraft narrow-angle camera on July 3, 2004, at a distance of about 789,000 kilometers (491,000 miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 114 degrees. The image scale is 4.7 kilometers (2.9 miles) per pixel. 
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Crescent Titan
NASA's Cassini spacecraft took this raw image of Saturn's moon Titan on Oct. 14, 2010, kicking off an action-packed long weekend that took the spacecraft by eight other moons. The camera was pointing toward Titan at approximately 207,643 kilometers (129,023 miles) away. This image has not been validated or calibrated. 
Image credit: NASA/JPL/SSI
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Titan and Tethys
NASA's Cassini spacecraft obtained this raw image of Saturn's moons Titan and Tethys on Oct. 18, 2010. Titan, Saturn's largest moon, is the larger, hazy moon in the background. Tethys is the bright icy moon in the foreground. The rings of Saturn faintly etch the top of this image. The image has not been validated or calibrated. 
Image credit: NASA/JPL/SSI
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Bright streaks of clouds on Titan
NASA's Cassini spacecraft obtained this raw image of Saturn's moon Titan on Oct. 18, 2010. Bright clouds streak the moon's midsection, likely an indication of changing seasons and the arrival of spring in the northern hemisphere. Cassini's imaging camera was about 2.5 million kilometers (1.5 million miles) away from Titan. The rings of Saturn faintly etch the top of this image. The image has not been validated or calibrated. 
Image credit: NASA/JPL/SSI
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Titan's Arrow-Shaped Storm
A huge arrow-shaped storm blows across the equatorial region of Titan in this image from NASA's Cassini spacecraft, chronicling the seasonal weather changes on Saturn's largest moon. 
This storm created large effects in the form of dark -- likely wet -- areas on the surface of the moon, visible in later images. After this storm dissipated, Cassini observed significant changes on Titan's surface at the southern boundary of the dune field named Belet. Those changes covered an area of 500,000 square kilometers (193,000 square miles), or roughly the combined area of Arizona and Utah in the United States. See PIA12818 to learn more.
The part of the storm that is visible here measures 1,200 kilometers (750 miles) in length east-to-west. The wings of the storm that trail off to the northwest and southwest from the easternmost point of the storm are each 1,500 kilometers (930 miles) long. 
Titan's weather has been changing since the August 2009 equinox, when the sun lay directly over the equators of Saturn and its moons, and storms at low latitudes are now more common. See PIA11667 to learn how the sun's illumination of the Saturnian system changed during the equinox transition to spring in the northern hemispheres and to fall in the southern hemispheres of the planet and its moons. See PIA12813 to learn more about Titan's changing weather. 
This image is a mosaic of two Cassini images. Most of this view is from an image of the storm captured on Sept. 27, 2010. However, because that image's framing cut off the south polar region of the moon, a second image taken on July 9, 2010, was used to fill in that portion of the moon. This second image was re-projected to the same viewing geometry as the first. 
Lit terrain seen here is in the area between the trailing hemisphere, which is the side of Titan that faces backward in its orbit around Saturn, and the side of Titan that always faces away from Saturn. North on Titan (5,150 kilometers or 3,200 miles across) is up. The images were taken with the Cassini spacecraft narrow-angle camera using a spectral filter of near-infrared light centered at 938 nanometers. The view was acquired at a distance of approximately 1.3 million kilometers (808,000 miles) from Titan and at a sun-Titan-spacecraft, or phase, angle of 44 degrees. Image scale is 8 kilometers (5 miles) per pixel. 
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Equatorial Titan Clouds
NASA's Cassini spacecraft chronicles the change of seasons as it captures clouds concentrated near the equator of Saturn's largest moon, Titan. 
Methane clouds in the troposphere, the lowest part of the atmosphere, appear white here and are mostly near Titan's equator. The darkest areas are surface features that have a low albedo, meaning they do not reflect much light. Cassini observations of clouds like these provide evidence of a seasonal shift of Titan's weather systems to low latitudes following the August 2009 equinox in the Saturnian system. (During equinox, the sun lies directly over the equator. See PIA11667 to learn how the sun's illumination of the Saturnian system changed during the equinox transition to spring in the northern hemispheres and to fall in the southern hemispheres of the planet and its moons.) 
In 2004, during Titan's late southern summer, extensive cloud systems were common in Titan's south polar region (see PIA06110, PIA06124 and PIA06241). Since 2005, southern polar systems have been observed infrequently, and one year after the equinox, extensive near-equatorial clouds have been seen. This image was taken on Oct. 18, 2010, a little more than one Earth year after the Saturnian equinox, which happens once in roughly 15 Earth years. 
The cloud patterns observed from late southern summer to early southern fall on Titan suggest that Titan's global atmospheric circulation is influenced by both the atmosphere and the surface. The temperature of the surface responds more rapidly to changes in illumination than does the thick atmosphere. Outbreaks such as the clouds seen here may be the Titan equivalent of what creates the Earth's tropical rainforest climates, even though the delayed reaction to the change of seasons and the apparently sudden shift is more reminiscent of the behavior over Earth's tropical oceans than over tropical land areas. 
A few clouds can be seen in Titan's southern latitudes here. See PIA12813 for a movie of clouds moving through the middle southern latitudes of Titan. 
Some clouds are also visible in the high northern latitudes here. See PIA12811 and PIA12812 for movies showing clouds near the moon's north pole. 
This view looks toward the Saturn-facing side of Titan (5,150 kilometers or 3,200 miles across). North is up. The image appears slightly grainy because it was re-projected to a scale of 6 kilometers (4 miles) per pixel. Scale in the original image was 15 kilometers (9 miles) per pixel. 
This view consists of an average of three images taken using a filter sensitive to near-infrared light centered at 938 nanometers, which allows for detection of Titan's surface and lower atmosphere, plus an image taken using a filter sensitive to visible light centered at 619 nanometers. 
The images were taken with the Cassini spacecraft's narrow-angle camera at a distance of approximately 2.5 million kilometers (1.6 million miles) from Titan and at a sun-Titan-spacecraft, or phase, angle of 56 degrees. 
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Tortula Facula
These side-by-side images obtained by NASA's Cassini spacecraft show the feature named Tortola Facula on Saturn's moon Titan. The left image was obtained by the visual and infrared mapping spectrometer data on Oct. 26, 2004, at a resolution of 2 kilometers (1 mile) per pixel This mosaic focuses on an area around 9 degrees north latitude and 145 degrees west longitude. In 2005, scientists interpreted Tortola Facula as an ice volcano. 
The right image shows the same feature, as seen by Cassini's radar instrument on May 12, 2008, at a much higher resolution of 300 meters per pixel. Scientists now think that this feature is a nondescript obstacle surrounded by obvious wind-blown sand dunes, similar to those commonly found in this region of Titan. In radar images, objects appear bright when they are tilted toward the spacecraft or have rough surfaces. 
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Titan and Callisto
These images compare surface features observed by NASA's Cassini spacecraft at the Xanadu region on Saturn's moon Titan (left), and features observed by NASA's Galileo spacecraft on Jupiter's cratered moon Callisto (right). The Cassini radar image, obtained on a Titan flyby April 30, 2006, is centered on 10 degrees south latitude and 85 degrees west longitude. The Galileo camera image, obtained on June 25, 1997, is centered on 6 degrees south latitude and 7 degrees west longitude. Titan may originally have had a cratered landscape similar to Callisto that has since been eroded by rainfall and runoff. There are many large circular features in Titan's Xanadu region that have some of the characteristics of impact craters - such as central peaks and inward-facing circular cliffs - which make scientists think they are, in fact, eroded impact craters. The surface of Callisto also has a substantially eroded cratered landscape. Instead of erosion by weather, scientists theorize the erosion on Callisto was caused by ground ice evaporating away. 
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Moons Small to Large
The Cassini spacecraft views Saturn with a selection of its moons in varying sizes. 
Saturn's largest moon, Titan, is in the center of the image. Titan is 5,150 kilometers, or 3,200 miles, across. The smaller moon Enceladus (504 kilometers, or 313 miles across) is on the far right, appearing just below the rings. The tiny moon Pandora (81 kilometers, or 50 miles across) is barely detectable as a speck on the far left, beyond the thin F ring. To enhance visibility, 
Pandora has been brightened by a factor of two relative to the rest of the image. 
This view looks toward anti-Saturn side of Titan and toward the northern, sunlit side of the rings from just above the ringplane. The image was taken with the Cassini spacecraft wide-angle camera on Jan. 15, 2011 using a combination of polarized and spectral filters sensitive to wavelengths of near-infrared light centered at 752 nanometers. The view was acquired at a distance of approximately 844,000 kilometers (524,000 miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 78 degrees. Image scale is 50 kilometers (31 miles) per pixel.
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Slicing Before Titan
Saturn's rings cut across this view of the planet's largest moon, Titan. 
Dark albedo features on Titan (5,150 kilometers, or 3,200 miles across) and the moon's north polar hood are visible here. See PIA08137 and PIA09739 to learn more. 
This view looks toward the southern, unilluminated side of the rings from just below the ringplane and toward the Saturn-facing side of Titan. North on Titan is up. The image was taken with the Cassini spacecraft narrow-angle camera on May 12, 2011 using a spectral filter sensitive to wavelengths of near-infrared light centered at 938 nanometers. The view was acquired at a distance of approximately 2.3 million kilometers (1.4 million miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 11 degrees. Image scale is 14 kilometers (9 miles) per pixel.
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Craters Before Haze
The Cassini spacecraft views the cratered surface of Saturn's moon Tethys in front of the hazy orb of the planet's largest moon, Titan.Tethys (1,062 kilometers, or 660 miles across) is much closer than Titan (5,150 kilometers, or 3,200 miles across) to Cassini. This view looks toward the Saturn-facing side of Titan and toward the area between the trailing hemisphere and anti-Saturn side of Tethys. Saturn is out of the frame, far to the left. The image was taken in visible green light with the Cassini spacecraft narrow-angle camera on July 14, 2011. The view was acquired at a distance of approximately 3.2 million kilometers (2 million miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 18 degrees. Image scale is 19 kilometers (12 miles) per pixel on Titan. The view was acquired at a distance of approximately 1.9 million kilometers (1.2 million miles) from Tethys and at a Sun-Tethys-spacecraft, or phase, angle of 18 degrees. Image scale is 11 kilometers (7 miles) per pixel on Tethys.
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East of Huygens
Saturn's rings lie in the distance as the Cassini spacecraft looks toward Titan and its dark region called Shangri-La, east of the landing site of the Huygens Probe. 
The moon's north polar hood is also visible here. See PIA09739 and PIA08137 to learn more about Titan's atmosphere. 
This view looks toward the anti-Saturn side of Titan (5,150 kilometers, or 3,200 miles across). North on Titan is up. This view looks toward the northern, sunlit side of the rings from just above the ringplane. 
The image was taken with the Cassini spacecraft narrow-angle camera on Aug. 9, 2011 using a spectral filter sensitive to wavelengths of near-infrared light centered at 938 nanometers. The view was acquired at a distance of approximately 1.4 million kilometers (870,000 miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 35 degrees. Image scale is 8 kilometers (5 miles) per pixel. 
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Titan's Kraken Mare
The Cassini spacecraft looks toward Saturn's largest moon, Titan, and spies the huge Kraken Mare in the moon's north. 
Kraken Mare, a large sea of liquid hydrocarbons, is visible as a dark area near the top of the image. See PIA12811 and PIA11626 to learn more. 
This view looks toward the Saturn-facing side of Titan (3,200 miles across, or 5,150 kilometers,). North on Titan is up and rotated 29 degrees to the left. 
The image was taken with the Cassini spacecraft narrow-angle camera on Sept. 14, 2011 using a spectral filter sensitive to wavelengths of near-infrared light centered at 938 nanometers. The view was acquired at a distance of approximately 1.2 million miles (1.9 million kilometers) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 26 degrees. Image scale is 7 miles (12 kilometers) per pixel. 
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Orange and Blue Hazes
These views from Cassini look toward the south polar region of Saturn's largest moon, Titan, and show a depression within the moon's orange and blue haze layers near the south pole. 
The close-up view was captured with the narrow-angle camera. Another view taken a second later with the wide-angle camera is also included here for context. 
The moon's high altitude haze layer appears blue here whereas the main atmospheric haze is orange. The difference in color could be due to particle size of the haze. The blue haze likely consists of smaller particles than the orange haze. 
The depressed or attenuated layer appears in the transition area between the orange and blue hazes about a third of the way in from the left edge of the narrow-angle image. The moon's south pole is in the upper right of this image. This view suggests Titan's north polar vortex, or hood, is beginning to flip from north to south. SeePIA11603 and PIA11667. 
The southern pole of Titan is going into darkness with the sun advancing towards the north with each passing day. The upper layer of Titan's hazes is still illuminated by sunlight. 
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were obtained on Sept. 11, 2011 at a distance of approximately 83,000 miles (134,000 kilometers) from Titan. Image scale is 2,581 feet (787 meters) per pixel. 
Image credit: NASA/JPL-Caltech/Space Science Institute
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True Colors, Deceptive Sizes
Saturn's largest moon, Titan, appears deceptively small paired here with Dione, Saturn's third-largest moon, in this view from Cassini. 
Titan (3200 miles, 5150 kilometers across) is much farther from the spacecraft than Dione (698 miles, 1123 kilometers across) is in this view. The view was captured at a distance of approximately 684,000 miles (1.1 million kilometers) from Titan but only about 85,000 miles (136,000 kilometers) from Dione. 
Titan appears in true color but has been brightened by a factor of about 1.6 relative to Dione. This view looks toward the Saturn-facing side of Titan and the area between the Saturn-facing side and leading hemisphere of Dione. North is up on the moons. 
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were obtained with the Cassini spacecraft wide-angle camera on Nov. 6, 2011. Scale in the original image was 5 miles (8 kilometers) per pixel on Dione and 41 miles (66 kilometers) per pixel on Titan. The image has been magnified by a factor of 1.5 and contrast-enhanced to aid visibility. 
Image credit: NASA/JPL-Caltech/Space Science Institute
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Titan Upfront
The colorful globe of Saturn's largest moon, Titan, passes in front of the planet and its rings in this true color snapshot from NASA's Cassini spacecraft. 
The north polar hood can be seen on Titan (3200 miles, 5150 kilometers across) and appears as a detached layer at the top of the moon here. See PIA08137 and PIA09739 to learn more about Titan's atmosphere and the north polar hood. 
This view looks toward the northern, sunlit side of the rings from just above the ring plane. 
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were obtained with the Cassini spacecraft narrow-angle camera on May 21, 2011 at a distance of approximately 1.4 million miles (2.3 million kilometers) from Titan. Image scale is 9 miles (14 kilometers) per pixel on Titan. 
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Titan and Dione
Saturn's third-largest moon Dione can be seen through the haze of its largest moon, Titan, in this view of the two posing before the planet and its rings from NASA's Cassini spacecraft. 
The north polar hood can be seen on Titan appearing as a detached layer at the top of the moon here. See PIA08137 and PIA09739 to learn more about Titan's atmosphere and the north polar hood. 
See PIA10560 and PIA07638 to learn more about and see a closer view of the wisps on Dione's trailing hemisphere, which appear as bright streaks here. 
This view looks toward the anti-Saturn side of Titan (3200 miles, 5150 kilometers across) and Dione (698 miles, 1123 kilometers across). North is up on the moons. This view looks toward the northern, sunlit side of the rings from just above the ring plane. 
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were obtained with the Cassini spacecraft narrow-angle camera on May 21, 2011 at a distance of approximately 1.4 million miles (2.3 million kilometers) from Titan 2 million miles (3.2 million kilometers) from Dione. Image scale is 9 miles (14 kilometers) per pixel on Titan and 12 miles (19 kilometers) on Dione. 
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Haze Before Ice
Saturn's moon Tethys, with its stark white icy surface, peeps out from behind the larger, hazy, colorful Titan in this Cassini view of the two moons. Saturn's rings lie between the two. 
The north polar hood can be seen on Titan appearing as a detached layer at the top of the moon here. See PIA08137 and PIA09739 to learn more about Titan's atmosphere and the north polar hood. 
Ithaca Chasma, a long series of scarps or cliffs on Tethys, faintly can be seen running north-south on that moon. See PIA10460 to learn more. 
This view looks toward the anti-Saturn side of Titan (3200 miles, 5150 kilometers across) and the Saturn-facing side of Tethys (660 miles, 1062 kilometers across). This view looks toward the northern, sunlit side of the rings from just above the ring plane. 
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were acquired with the Cassini spacecraft narrow-angle camera on May 21, 2011 at a distance of approximately 1.4 million miles (2.3 million kilometers) from Titan and 2.4 million miles (3.8 million kilometers) from Tethys. Image scale is 9 miles (14 kilometers) per pixel on Titan and 18 miles (27 kilometers) per pixel on Tethys. 
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Welcome Disruption
Rhea Before Titan
Craters appear well defined on icy Rhea in front of the hazy orb of the much larger moon Titan in this Cassini spacecraft view of these two Saturn moons. 
See PIA08137 and PIA14913 to learn more about the hazy atmosphere on Titan (3,200 miles, or5,150 kilometers across). See PIA07763 and PIA11465 for closer views of craters on Rhea (949 miles, or 1,528 kilometers across). 
Lit terrain seen here is on the leading hemispheres of Rhea and Titan. North on the moons is up and rotated 13 degrees to the left. The limb, or edge of the visible disk, of Rhea is slightly overexposed in this view. 
The image was taken in visible green light with the Cassini spacecraft narrow-angle camera on Dec. 10, 2011. The view was acquired at a distance of approximately 1.2 million miles (2 million kilometers) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 109 degrees. The view was acquired at a distance of approximately 810,000 miles (1.3 million kilometers) from Rhea and at a Sun-Rhea-spacecraft, or phase, angle of 109 degrees. Image scale is 8 miles (12 kilometers) per pixel on Titan and 5 miles (8 kilometers) per pixel on Rhea. 
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Fotos; NASA

2381 Views

Samstag, 21. Juni 2014 - 19:00 Uhr

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Kleiner Nachrichten-Break auf diesem Blog wegen Grillzeit mit zweiten Spiel von Deutschland gegen Ghana!


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Samstag, 21. Juni 2014 - 17:57 Uhr

Raumfahrt - Neue chinesische Bedrohung der US-Raumfahrtsysteme

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Last year, China launched a mysterious missile from its southwest region. While Chinese news sources said it was a scientific experiment, there is widespread speculation that the payload was a more advanced anti-satellite test.
Satellites are vulnerable to an array of weapons and disruptive technologies like anti-satellite missiles and sophisticated cyber attacks that can have potentially devastating results from degrading capabilities to complete annihilation, experts said.
There is strong evidence that the anti-satellite weapon China tested in May 2013 went higher than low-Earth orbit, said Charles Miller, president of NextGen Space LLC, a space and public policy consulting group. If China continues to make strides and develops weapons that reach farther, it could one day threaten key satellites in geosynchronous orbit. 
The damage caused by an anti-satellite missile is two-fold: Not only does it destroy its target, but it also causes a massive ripple affect with debris from the collision striking other satellites. China’s 2007 test created a large debris field, which could damage other spacecraft, said Gen. William Shelton, commander of Air Force Space Command.
The Air Force in June took new steps to better track and observe man-made debris in space. The service awarded Lockheed Martin a $915 million contract to develop the Space Fence, which has been in the works for years and is now entering final system development with the delivery of increment 1 and an operations center. The system will track objects in low-Earth orbit and some in higher orbits. The Air Force plans to have the system operational by 2019, and the contract leaves open the possibility for a second radar site.
In February, Director of National Intelligence James R. Clapper said potential adversaries are hard at work developing weapons that could degrade or destroy some of the United States’ key satellites that provide essential communication to the military, the government and U.S. citizens.
“Threats to U.S. space services will increase during 2014 and beyond, as potential adversaries pursue disruptive and destructive counter-space capabilities,” Clapper told the Senate Armed Services Committee. “Chinese and Russian military leaders understand the unique information advantages afforded by space systems and are developing capabilities to disrupt the United States’ use of space in a conflict.”
In the months since his testimony, top U.S. military officials and policy analysts have echoed the same concern. As U.S. dependence on satellites grows, so does the vulnerability of its space assets.
Satellites beam essential information down to Earth. From mapping services to phone calls to Internet access, both the military and civilian world rely on timely and secure connections. The armed services use GPS satellites to guide unmanned aerial vehicles, missiles and other weapons. Reconnaissance satellites track enemy movements.
The military utility of satellite technology cannot be understated, said Shelton. Capabilities provided by satellites help the military conduct humanitarian, disaster relief and combat operations, he said. 
“In space, our sustained mission success integrating these [satellite] capabilities into our military operations has encouraged potential adversaries to further develop counterspace technologies and attempt to exploit our systems and information. Therefore, I believe we are at a strategic crossroad in space,” Shelton said before the SASC in March.
“We are so dependent on space these days. We plug into it like a utility. It is always there. Nobody worries about it,” Shelton said. “You do not even know sometimes that you are touching space. So [to lose our space capabilities] it would be almost a reversion back to … industrial-based warfare.”
Bill Ostrove, a space systems analyst at Forecast International, a Newtown, Connecticut-based marketing and consulting firm, agreed that the military stands to lose much in the event of an attack on satellite systems.
“If satellites are knocked out, even temporarily, it could have serious consequences on the military’s ability to operate effectively,” Ostrove said.
Anti-satellite missiles are one of the most serious threats to space assets, he said.
“There are a few different ways that a satellite could be disabled that the United States is afraid of. The most obvious way is to launch a missile into space that targets a satellite,” Ostrove said. “The United States has a legitimate fear of anti-satellite weapons.”
In 2007, China successfully launched an anti-satellite missile into low-Earth orbit and destroyed one of its aging weather satellites.
The test is concerning because it means China could potentially target a U.S. satellite in low-Earth orbit. The U.S. military is monitoring China’s development of the weapons, Shelton said.
“We are concerned about low-Earth orbit because we saw the 2007 Chinese ASAT test, which was a success,” Shelton said. “We are concerned about work that we have seen since then that includes all the way up to geosynchronous orbit. Some of our most precious assets fly in geosynchronous orbit.”
Low-earth orbit is defined as 160 to 2,000 kilometers above the Earth’s surface. Most spacecraft fly in it, as does the International Space Station. Satellites in geosynchronous orbit fly about 36,000 kilometers above the Earth’s equator. 
As for the 2013 test, it was likely disguised as a research experiment, Miller said, citing a study by the Secure World Foundation, a Broomfield, Colorado-based private foundation that works to keep space sustainable. The rocket reached more than 10,000 kilometers in altitude and then released a canister of barium powder, the report found.
The test is alarming because satellites in geosynchronous orbit are vulnerable, Miller said in May during a panel discussion on space threats at the American Security Project, a Washington, D.C.-based think tank.
“Most of the United States’ assets in space for national security are in geosynchronous orbit. They are completely fragile,” Miller said.
The advanced extremely high frequency system, which provides the U.S. and allied militaries with secure communications, is one example of a key satellite that flies in the orbit and could one day be targeted by adversaries.
Xinhua, China’s state-run news service, said the May 2013 rocket was launched from the Xichang Satellite Launch Center in southwest China and meant to “investigate energetic particles and magnetic fields in the ionized stratum and near-Earth space.”
A U.S.-China Economic and Security Review Commission paper titled, “China Missile Launch May Have Tested Part of a New Anti-Satellite Capability,” said if the launch was indeed an anti-satellite test and not a research experiment, it would show that China is not being transparent about its space objectives. It may also signal that China is attempting to develop weapons that could destroy crucial U.S. satellites, it said.
“Such a test would signal China’s intent to develop an ASAT capability to target satellites in an altitude range that includes U.S. GPS and many U.S. military and intelligence satellites,” the report said. “In a conflict, this could allow China to threaten the U.S. military’s ability to detect foreign missiles and provide secure communications, navigation and precision missile guidance.” 
China’s 2007 test created 3,000 new pieces of debris, according to the National Security Space Strategy of 2011, the Defense Department’s most recent guidance on space issues. Another 1,500 pieces of debris were created when a Russian and U.S. satellite collided in 2009. 
The military tracks about 23,000 objects in orbit, Shelton said. About 1,000 of them are active payloads, and the rest include defunct satellites, pieces of debris and other items, he said.
Military sensors generally can track objects that are larger than 10 centimeters across, Shelton said. However, there could be 500,000 man-made objects in orbit that are smaller than that and can cause significant damage to satellites, he said.
The military is also working to ensure that adversaries do not attack satellites through cyber intrusions, Shelton said.
“We are going system by system looking at our cyber vulnerabilities, and we have a large information assurance program that gets into those vulnerabilities and patches them and tries to prevent access,” he said. “In many cases, these are closed systems. That does not mean there are not vulnerabilities, but they are … not accessible through the Internet. So it would take insider — special access — those kinds of things to get to these closed networks.”
Some countries, such as China, are also developing technologies that use lasers to “dazzle” a satellite, said Micah Walter-Range, director of research and analysis at the Space Foundation, a Colorado Springs-based advocacy group. By shining lasers at the craft, adversaries overload the satellite’s sensors and can temporarily blind or permanently damage it, he said.
While a degradation of the capabilities provided by the nation’s space assets would hurt the military, it would also be detrimental for the general public, said Mariel Borowitz, an assistant professor at the Sam Nunn School of International Affairs at the Georgia Institute of Technology, who studies space issues. Television, Internet access, radio and telephone service could go dark, she said.
“The threat to satellite technology is serious. The United States has more satellites than any other country in the world, and satellite technologies are critical to both our economic system and our military,” Borowitz said.
Economically, the country relies on GPS for logistical, agricultural and safety applications. Boaters and pilots also rely heavily on weather satellites, Borowitz said.
The U.S. government is looking at numerous ways to prevent and mitigate attacks or vulnerabilities. 
Disaggregation, which takes one large satellite and splits it into smaller spacecraft is one way to protect satellite capabilities, Shelton said. If an enemy attacks the system and takes out a few satellites, there will still be some functionality left, he said.
“By separating payloads on different satellites we will complicate a potential adversary’s targeting calculus, decrease size and system complexity and enable use of smaller boosters — with the goal of simultaneously driving down cost,” Shelton said.
Satellites should be built with greater resiliency before they are launched, said Peter Wegner, director of advanced concepts at Utah State University Space Dynamics Laboratory.
Systems must be hardened so in the event of an attack they can return to their original state and continue providing necessary capabilities, he said. 
International treaties are another way the United States could mitigate a future attack, said Douglas Loverro, deputy assistant secretary of defense for space policy, during his testimony before the SASC in March.
The Defense Department is working with the State Department to establish an international code of conduct for responsible space use, he said. It would include standards for “debris limitation, launch notification, on-orbit monitoring and collision avoidance.”
While a set of standards will not necessarily deter all space-faring countries from irresponsible actions, it will help keep space sustainable, he said.
“I am not so naïve as to believe that a simple set of rules will solve all of the major issues we face — they will not; nor would I expect that they will inhibit those who would try to threaten our use of space,” Loverro said. “But common sense rules that can be embraced by a majority of space-faring nations will help stem the rise of uncontrollable debris, add demonstrably to spaceflight safety and clearly differentiate those who use space responsibly from those who do not.”
Quelle: National Defense Industrial Association

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Samstag, 21. Juni 2014 - 16:30 Uhr

Astronomie - Supererde oder Minineptun? – Planetenforscherin beobachtet Transit eines Exoplaneten mit SOFIA

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Künstlerische Darstellung des Exoplaneten GJ 1214b

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Wissenschaftler des Deutschen Zentrums für Luft- und Raumfahrt (DLR) beobachteten mit Hilfe des Stratosphärenobservatoriums SOFIA einen Planeten außerhalb unseres Sonnensystems. Die Untersuchung der Atmosphäre soll entscheiden, ob es sich bei dem Exoplaneten um eine Supererde oder einen Minineptun handelt. Mit Dr. Claudia Dreyer war erstmals eine wissenschaftliche Projektleiterin des DLR (Principal Investigator) an Bord des Forschungsflugzeugs.
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Stratosphärenobservatorium SOFIA
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GJ 1214b lautet der Name des Exoplaneten, der sich 40 Lichtjahre von der Erde entfernt befindet. Zum Zeitpunkt seiner Entdeckung 2009 galt er als zweiter erdähnlicher Planet nach CoRoT-7b. Allerdings lässt die mittlere Dichte, die aus den unabhängigen Messungen von Masse und Radius bestimmt werden konnte, die Vermutung zu, es könne sich um einen neptun-ähnlichen Planeten handeln. Wissenschaftler der Abteilung Extrasolare Planeten und Atmosphären des DLR-Instituts für Planetenforschung beobachteten mit den Instrumenten des Stratosphärenobservatoriums SOFIA den Transit des Planeten in mehreren Wellenlängen, um seine Atmosphäre genauer bestimmen zu können. Dabei bietet SOFIA den Forschern beste Möglichkeiten, Exoplaneten in verschiedenen Wellenlängen genauer zu beobachten und letztlich auch die Art der Atmosphäre bestimmen zu können. Mit SOFIA kann in Wellenlängen beobachtet werden, die sonst nur von einem Weltraumteleskop erfasst werden, weil sie in der Erdatmosphäre absorbiert werden. Zudem ist das Stratosphärenobservatorium durch die tägliche Rückkehr zur Erde flexibel, um Geräte und Filter auszutauschen.
Supererde oder Minineptun?
GJ 1214b wurde mit Hilfe der Transitmethode entdeckt. Dabei bezeichnet "Transit" die regelmäßige Bedeckung des Zentralsterns durch den Planeten, wodurch dessen Licht geschwächt wird. Durch diese Methode konnte der Radius des Planeten bestimmt werden. Etwa 2,7 Erdradien misst der Exoplanet. Zudem konnte durch die Radialgeschwindigkeitmethode seine Masse auf 6,5 Erdmassen ermittelt werden. Aus beiden Daten lässt sich wiederum die Dichte des Himmelskörpers ermitteln, wodurch Aussagen über die mögliche Zusammensetzung des Planeten getätigt werden können, beispielsweise ob es ein Gesteins- oder Gasplanet ist. Demnach könnte es sich bei dem Exoplaneten um einen Gesteinsplaneten mit einer ausgedehnten Atmosphäre, der die Dichte von Wasser hat, handeln.
Für präzisere Bestimmungen der Zusammensetzung des Planeten muss die Atmosphäre untersucht werden. "Besteht die Atmosphäre überwiegend aus Wasserdampf, spricht dies dafür, dass es sich um einen Ozeanplaneten handelt - also ein Planet, dessen Oberfläche zum größten Teil durch Wasser bedeckt ist", sagt Dr. Claudia Dreyer, Projektleiterin. "Einen vergleichbaren Planeten gibt es nicht in unserem Sonnensystem", so Dreyer weiter. Ließe sich hingegen eine wasserstoffreiche Atmosphäre mit Wolken nachweisen, wäre es ein Planet ähnlich dem Neptun. Allerdings wäre er leichter als der Neptun und könnte daher eher als "Minineptun" bezeichnet werden. 
Momentan liegen unterschiedliche Untersuchungsergebnisse von Wissenschaftler vor, die beide Theorien stützen. Die Berliner Planetenforscher analysieren nun die Daten aus der Beobachtung in unterschiedlichen Wellenlängen. Bislang fußen die Theorien auf Beobachtungen entweder nur im infraroten oder nur im visuellen Spektralbereich. "Mit den Untersuchungen von SOFIA haben wir gleichzeitig in diesen beiden Spektralbereichen Messungen durchgeführt und darüber hinaus um eine Wellenlänge ergänzt, in der bislang noch nicht beobachtet wurde.", sagt Dreyer. Vorteil einer derartigen Vorgehensweise ist, dass die Daten den gleichen stellaren Bedingungen unterliegen, denn Helligkeitsschwankungen eines Sterns können zu unterschiedlichen Ergebnissen führen.
52 Minuten lang beobachtete Dreyer mit SOFIA den Transit. „Die vollständige Auswertung der Daten wird noch einige Zeit andauern. Wir sind sehr zuversichtlich, dass wir dadurch zur Diskussion beitragen können, um was für eine Art Planet es sich bei GJ 1214b handelt“, beschreibt Dreyer die Aufgaben in den kommenden Wochen.
Über SOFIA
SOFIA, das Stratosphären Observatorium Für Infrarot Astronomie, ist ein Gemeinschaftsprojekt des Deutschen Zentrums für Luft- und Raumfahrt (DLR; Förderkennzeichen: 50OK0901) und der National Aeronautics and Space Administration (NASA). Es wird auf Veranlassung des DLR mit Mitteln des Bundesministeriums für Wirtschaft und Energie aufgrund eines Beschlusses des Deutschen Bundestages und mit Mitteln des Landes Baden-Württemberg und der Universität Stuttgart durchgeführt. Der wissenschaftliche Betrieb wird auf deutscher Seite vom Deutschen SOFIA Institut (DSI) der Universität Stuttgart koordiniert, auf amerikanischer Seite von der Universities Space Research Association (USRA). Die Entwicklung der deutschen Instrumente ist finanziert mit Mitteln der Max-Planck-Gesellschaft (MPG) und der Deutschen Forschungsgemeinschaft (DFG).
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Transmissionsspektrum von GJ 1214b
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Quelle: DLR

2296 Views

Samstag, 21. Juni 2014 - 16:15 Uhr

Raumfahrt - Alexander Gerst beobachtet aus ISS den Start von GLONASS

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Looks like something launched into space Saturday 14 June UTC 17:25 over Northern Russia, possibly a GLONASS Sat from Plesetsk.
Habe 14-06-2014 um 17:25 UTC einen Raketenstart über Nordrussland gesehen, möglicherweise ein GLONASS Sat von Plesetsk.
Credits: ESA/NASA
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Fotos: ESA/NASA

2279 Views

Samstag, 21. Juni 2014 - 12:56 Uhr

Luftfahrt - Mehr als 400 US-Drohnen seit 2001 abgestürzt

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Mehr als 400 große Drohnen der US-Armee sind nach einem Bericht der "Washington Post" seit 2001 weltweit abgestürzt. Die Zeitung wertete für ihren Beitrag mehr als ein Jahr lang über 50.000 Seiten mit Unfallberichten des Militärs aus.

Bei den insgesamt 418 größeren Unfällen kamen demnach keine Menschen zu Schaden, tödliche Vorfälle wurden in einigen Fällen jedoch nur knapp vermieden. So stürzte eine Drohne in unmittelbarer Nähe einer Grundschule im US-Bundesstaat Pennsylvania ab.
Air-Force-Flugzeug von Drohne beschädigt
Die meisten Abstürze (67) ereigneten sich in Afghanistan. In den USA waren es 47, im Irak 41. Weitere Unfälle gab es unter anderem in der Nähe von Dschibuti, in Pakistan und in Mali.
Der gefährlichste Vorfall ereignete sich im August 2011 in Afghanistan: Dort flog eine Drohne in ein bemanntes Air-Force-Flugzeug. Der linke Flügel war getroffen und Treibstoff trat aus. Jedoch konnte der Pilot das Flugzeug schnell landen, so dass niemand zu Schaden kam.
Technische Defekte, menschliches Versagen: die Ursachen der Abstürze
Ursachen waren meist technische Defekte, schlechtes Wetter, aber auch fehlende Kollisionswarnsysteme, Pilotenfehler und die oft zusammenbrechende Satellitenverbindung zwischen Pilot und Drohne
Die "Washington Post" befasste sich allerdings nur mit Abstürzen großer unbemannter Angriffs- oder Überwachungsflugzeuge vom Typ Predator, Global Hawk, Reaper, Hunter oder Grey Eagle. Insgesamt verfügt die US-Armee über tausende kleine Drohnen.
Drohne landete auf deutscher Autobahn
Auch in Deutschland hatte kürzlich eine Drohne beinahe einen Unfall verursacht: Eine fünf Kilogramm schwere ferngelenkte Drohne ist nach Angaben der Polizei offenbar neben der Autobahn 392 in Niedersachsen notgelandet.
Das Fluggerät sei bei Mäharbeiten auf dem Grünstreifen beim Ölper Kreuz gefunden worden, teilten die Beamten mit. Es dürfte notgelandet sein, nachdem es den Fernsteuerbereich des Piloten verlassen habe.
Drohneneinsätze für zivile Zwecke geplant
Der Bericht erscheint vor dem Hintergrund einer möglichen Legalisierung von Drohnenflügen zu zivilen Zwecken. Die US-Bundesluftfahrtbehörde prüft derzeit entsprechende Anträge.
Bis zum Jahr 2018 sollen mehr als 7500 Miniflugroboter umherfliegen dürfen. Für Dezember sind erste Tests in sechs US-Regionen geplant.
Quelle: t-online

2233 Views

Samstag, 21. Juni 2014 - 12:16 Uhr

Planet Erde - NASA-QuikScat erfasst gefährliche Wetterereignisse über den Ozeanen 6 bis 12 Stunden früher als bisher

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QuikScat's Eye on Ocean Winds Lives On with RapidScat

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Today (June 19) marks the 15th anniversary of the launch of NASA's QuikScat, a satellite sent for a three-year mission in 1999 that continues collecting data. Built in less than 12 months, QuikScat has watched ocean wind patterns for 15 years and improved weather forecasting worldwide. Despite a partial instrument failure in 2009, it provides calibration data to international partners.
On this anniversary, the mission's team is preparing to calibrate ISS-RapidScat, the successor that will maintain QuikScat’s unbroken data record. After its launch in a few months, RapidScat will watch ocean winds from the International Space Station (ISS) for a two-year mission.
Much like QuikScat, ISS-RapidScat was built in less than two years and at a fraction of its predecessor’s budget. Both missions are testaments to ingenuity, craftsmanship and speedy construction in the name of improving our understanding of Earth’s winds.
“Both ISS-RapidScat and QuikScat came about to react quickly to the failure of another spaceborne instrument,” said Ernesto Rodriguez, project scientist for the ISS-RapidScat mission at NASA’s Jet Propulsion Laboratory, Pasadena, California. “What differentiates these missions is cost and risk: RapidScat had to be built with a fraction of the QuikScat budget, and the mission accepted a much riskier approach,” Rodriguez said. RapidScat was constructed primarily from QuikScat’s spare parts and will be the first scatterometer to berth on the International Space Station.
Scatterometers help scientists estimate the speed and direction of winds at the ocean’s surface by sending microwave pulses to Earth’s surface. Strong waves or ripples scatter the microwaves, sending some of them back toward the scatterometer. Based on the strength of this backscatter, scientists can estimate the strength and direction of the wind at the ocean’s surface.
Scatterometer data are critical for observing global weather patterns. They also help ocean fishermen decide where to fish, ship captains choose shipping lanes and researchers track hurricanes, cyclones and El Niños.
“The usefulness of this wind measurement is enormous,” said JPL’s Jim Graf, who served as project manager for the QuikScat mission in the 1990s and is now the deputy director of JPL’s Earth Science and Technology Directorate. “One of the dominant factors in understanding the climate is to assess what is happening in the ocean circulation. And one of the dominant factors in ocean circulation is the wind at the surface, which is what scatterometers measure.”
NASA launched its first scatterometer satellite in 1978 and its second instrument, the NASA Scatterometer (NSCAT), on a Japanese satellite in 1996. Each lasted less than a year, but collected hundreds of times more data about ocean winds than ships or buoys and improved weather forecasts from the National Oceanic and Atmospheric Administration (NOAA).
But the spacecraft carrying NSCAT malfunctioned in 1997. Immediately, a team of JPL scientists and engineers raced to get a scatterometer satellite back into space.
“We had the idea that a partially developed spacecraft bus could be mated with an advanced version of the instrument that was already under development, and we could get something up quickly. So we went to NASA, and they said, ‘Okay, let’s give it a shot, but we want you to be ready to go one year from the go-ahead,’” Graf said. “And so we took off running, and we didn’t stop for a whole year.”
In that year, Ball Aerospace & Technologies Corp., Boulder, Colorado, built the QuikScat satellite bus while JPL finished the new SeaWinds scatterometer instrument. It launched in 1999. For the next decade, QuikScat made about 400,000 daily measurements of wind speed and direction. Over 15-mile (25-kilometer) segments of ocean, its measurements were detailed enough to estimate average wind speed within 6 feet (2 meters) per second.
The SeaWinds instrument on QuikScat used a rotating antenna to measure a swath of Earth’s surface 1,118 miles (1,800 kilometers) wide -- about the distance from Los Angeles to Seattle. As QuikScat flew, the rotations overlapped to cover more than 90 percent of Earth’s surface every day.
But by the end of 2009, long after the expected end of QuikScat’s mission, the lubricant coating the antenna’s bearings dried up. Instead of tracing a round swath on Earth’s surface, it pointed straight down and only watched the waves directly below it. Still, those data were sufficient to help calibrate newer satellites.
“Since 2009, we’ve been able to keep QuikScat operating quite successfully,” said QuikScat Project Manager Rob Gaston of JPL. “We used QuikScat’s highly successful backscatter measurements, which were well understood and had demonstrated stability, as a calibration standard for many instruments, including other scatterometers.” The European Space Agency and Indian Space Research Organization have both used QuikScat data to calibrate scatterometers in the last five years.
QuikScat’s final task will be to calibrate its successor, RapidScat. The satellite will continue collecting data until April 2015, when it will be decommissioned after nearly 16 years in orbit.
RapidScat, like QuikScat, was built in a fraction of the timeline for most missions. The two missions even share hardware: JPL engineers used SeaWinds test parts to build much of RapidScat, which also uses a rotating dish antenna.
RapidScat will launch aboard a SpaceX Dragon resupply mission this summer. Flying in the space station’s orbit means RapidScat will spend more time observing Earth's tropics than previous scatterometer satellites, which orbited farther north and south.
“RapidScat will be able to, for the first time, map the evolution of winds as the day progresses, which is important for understanding how clouds and precipitation develop, especially in the tropics, which are key regions in Earth's climate system,” Rodriguez said. “It will provide a common reference to tie all of these measurements together.”
Together with scatterometers managed by India and Europe, RapidScat will maintain the continuous climate record QuikScat began while adding its own unique perspective from orbit.
Quelle: NASA

2174 Views

Samstag, 21. Juni 2014 - 11:29 Uhr

Astronomie - Funkelnder Sirius im Spektrum des Regenbogen

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It's twinkle, twinkle with a whole new twist. Gaze up at Sirius, the brightest star in the night sky, and it seems to change colour as its light gets refracted through our atmosphere. This unique photo of the dog star in the Pakistan sky captures 2 seconds of this multicoloured twinkling.
Amateur astrophotographer Syed Roshaan created the photo by focusing a telescope sharply on Sirius, and then moving the telescope around while taking a long-exposure photograph with a DSLR camera.
The colours of the image were not enhanced digitally, although Roshaan did boost the contrast and brightness to make the track more visible.
Bukhari says he was surprised at the vivid colour he captured, which revealed beauty in effects that are normally the astrophotographer's nemesis. "This was the first time I could see the effects of the distortion of our atmosphere in a way that would not make me curse them," he says.
Quelle: D-News

2200 Views


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