23.11.2023
NASA's Psyche spacecraft just fired a laser 10 million miles away in deep space
Fast communications could speed up science on the asteroid mission.
A NASA laser just fired successfully in a deep-space test.
On Nov. 14, NASA picked up a laser signal fired from an instrument that launched with the Psyche spacecraft, which is currently more than 10 million miles (16 million kilometers) from Earth and heading toward a mysterious metal asteroid. (The spacecraft is at more than 40 times the average distance of Earth's moon, and still voyaging afar.)
The moment marked the first successful test of NASA's Deep Space Optical Communications (DSOC) system, a next-generation comms link that sends information not by radio waves but instead by laser light. It's part of a series of tests NASA is doing to speed up communications in deep space, on different missions.
"Achieving first light is a tremendous achievement. The ground systems successfully detected the deep space laser photons from DSOC," Abi Biswas, the system's project technologist at NASA's Jet Propulsion Laboratory (JPL) in Southern California, said in an agency statement.
"And we were also able to send some data, meaning we were able to exchange 'bits of light' from and to deep space," Biswas added.
Other missions have tried out laser comms in Earth orbit or on the way to the moon and back, but DSOC gives laser communications its trickiest, most distant test yet. If it's successful, NASA officials expect that astronauts of the coming decades, bound for the moon or for Mars, may use laser light as their means of taking with ground control.
This DSOC test began in California, at JPL's Table Mountain Facility. There, in the hills outside Los Angeles, engineers switched on an uplink beacon, a near-infrared laser pointed in Psyche's direction. About 50 seconds later, a transceiver on Psyche received the laser and relayed its own laser signal back to Palomar Observatory, near San Diego.
The task requires astronomical precision, and automated guidance systems help aim Psyche's own laser. But should the test work out, the benefits are high: Because laser light has shorter wavelengths than radio waves, using optical light would allow space missions to send 10 to 100 times more information per unit time than they currently do.
The Nov. 14 test marked "first light" for DSOC, and engineers will continue to test the system as Psyche voyages to its namesake asteroid, which resides in the asteroid belt between Mars and Jupiter. Psyche should get there in 2029, then spend 29 months surveying the bizarre metallic world.
Quelle: SC
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Update: 29.11.2023
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Psyche beam hits Earth from 16 million km away
NASA’s Psyche spaceship has fired a laser beam at Earth from 16 million kilometres away.
Contained within that laser is data and it marks the first ‘test fire’ of NASA’s Deep Space Optical Communications (DSOC) instrumentation, which was installed on the Psyche spacecraft for the six-year mission to its namesake US$1 quintillion asteroid.
As part of the experiment, DSOC sent a near-infrared light beam containing test data to Caltech’s Palomar Observatory in San Diego, California.
The process, dubbed ‘first light’, is one of several milestones NASA hopes to meet during the course of the Psyche mission. Two weeks ago, DSOC also transmitted data from near the Moon.
DSOC will continue transmitting laser-borne data to NASA over the next two years as part of the special technology demonstration. Success will likely see technology incorporated into future spacefaring missions for deep-space communication. The use of near-infrared lasers allows more data to be packed into light beams, enabling 10-100 times as much data to be transmitted than conventional radio waves.
An upcoming test will see the instrument stream video of Mars back to Earth as the Psyche spaceship drifts past the red planet.
“Achieving first light is one of many critical DSOC milestones in the coming months, paving the way toward higher-data-rate communications capable of sending scientific information, high-definition imagery, and streaming video in support of humanity’s next giant leap: sending humans to Mars,” said Trudy Kortes, director of technology demonstrations for NASA’s Space Technology Mission Directorate.
As part of the DSOC experiment, test data was sent using uplink lasers from NASA’s Jet Propulsion Lab facility in Wrightwood, California, and downlink lasers mounted to the instrument itself. The Wrightwood uplink laser provides a ‘beacon’ for the DSOC to find and target its downlink back to Earth.
Following the successful first test, the DSOC mission control will begin refining the downlink targeting systems for future experiments. Given changes in position as the spacecraft draws further away from the Earth, precision tracking is required, with data taking about 20 minutes to reach the Earth from its current position.
“Tuesday morning’s test was the first to fully incorporate the ground assets and flight transceiver, requiring the DSOC and Psyche operations teams to work in tandem,” said Meera Srinivasan, operations lead for DSOC at JPL. “It was a formidable challenge, and we have a lot more work to do, but for a short time, we were able to transmit, receive, and decode some data.”
While mounted on a Psyche spacecraft, DSOC is a separate mission to NASA’s asteroid explorer. Psyche is still ‘booting up’ as it travels towards its target, an asteroid believed to be the metallic remnants of a dead planet core.
Quelle: COSMOS
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Update: 7.12.2023
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NASA’s Psyche Delivers First Images and Other Data
The mission team has celebrated several successes since its launch from Kennedy Space Center on Oct. 13. The latest is the operation of the spacecraft’s cameras.
This mosaic of a star field in the constellation Pisces was made from “first light” images acquired Dec. 4 by both of the cameras on NASA’s Psyche spacecraft. Use the slider to view the star field with and without star names labeled. Credit: NASA/JPL-Caltech/ASU
NASA’s Psyche spacecraft is on a roll. In the eight weeks since it left Earth on Oct. 13, the orbiter has performed one successful operation after another, powering on scientific instruments, streaming data toward home, and setting a deep-space record with its electric thrusters. The latest achievement: On Monday, Dec. 4, the mission turned on Psyche’s twin cameras and retrieved the first images – a milestone called “first light.”
Already 16 million miles (26 million kilometers) from Earth, the spacecraft will arrive at its destination – the asteroid Psyche in the main asteroid belt between Mars and Jupiter – in 2029. The team wanted to test all of the science instruments early in the long journey to make sure they are working as intended, and to ensure there would be plenty of time to calibrate and adjust them as needed.
The imager instrument, which consists of a pair of identical cameras, captured a total of 68 images, all within a star field in the constellation Pisces. The imager team is using the data to verify proper commanding, telemetry analysis, and calibration of the images.
“These initial images are only a curtain-opener,” said Arizona State University’s Jim Bell, the Psyche imager instrument lead. “For the team that designed and operates this sophisticated instrument, first light is a thrill. We start checking out the cameras with star images like these, then in 2026 we’ll take test images of Mars during the spacecraft’s flyby. And finally, in 2029 we’ll get our most exciting images yet – of our target asteroid Psyche. We look forward to sharing all of these visuals with the public.”
The imager takes pictures through multiple color filters, all of which were tested in these initial observations. With the filters, the team will use photographs in wavelengths of light both visible and invisible to the human eye to help determine the composition of the metal-rich asteroid Psyche. The imager team will also use the data to create 3D maps of the asteroid to better understand its geology, which will give clues about Psyche’s history.
Solar Surprise
Earlier in the mission, in late October, the team powered on the magnetometer, which will provide crucial data to help determine how the asteroid formed. Evidence that the asteroid once had a magnetic field would be a strong indication that the body is a partial core of a planetesimal, a building block of an early planet. The information could help us better understand how our own planet formed.
Shortly after being powered on, the magnetometer gave scientists an unexpected gift: It detected a solar eruption, a common occurrence called a coronal mass ejection, where the Sun expels large quantities of magnetized plasma. Since then, the team has seen several of these events and will continue to monitor space weather as the spacecraft travels to the asteroid.
The good news is twofold. Data collected so far confirms that the magnetometer can precisely detect very small magnetic fields. It also confirms that the spacecraft is magnetically “quiet.” The electrical currents powering a probe of this size and complexity have the potential to generate magnetic fields that could interfere with science detections. Because Earth has its own powerful magnetic field, scientists obtained a much better measurement of the spacecraft magnetic field once it was in space.
In the Zone
On Nov. 8, amid all the work with the science instruments, the team fired up two of the four electric propulsion thrusters, setting a record: the first-ever use of Hall-effect thrusters in deep space. Until now, they’d been used only on spacecraft going as far as lunar orbit. By expelling charged atoms, or ions, of xenon gas, the ultra-efficient thrusters will propel the spacecraft to the asteroid (a 2.2-billion-mile, or 3.6-billion-kilometer journey) and help it maneuver in orbit.
Less than a week later, on Nov. 14, the technology demonstration built into the spacecraft, an experiment called Deep Space Optical Communications (DSOC), set its own record. DSOC achieved first light by sending and receiving optical data from far beyond the Moon. The instrument beamed a near-infrared laser encoded with test data from nearly 10 million miles (16 million kilometers) away – the farthest-ever demonstration of optical communications.
The Psyche team has also successfully powered on the gamma-ray detecting component of its third science instrument, the gamma-ray and neutron spectrometer. Next, the instrument’s neutron-detecting sensors will be turned on the week of Dec. 11. Together those capabilities will help the team determine the chemical elements that make up the asteroid’s surface material.
The data was collected as part of a highly orchestrated set of activities that have been carefully planned and rehearsed over the past three years. "Our commissioning activities succeeded beyond our expectations, and this success lays the groundwork for future operations during cruise and at asteroid Psyche," said Peplowski, the Psyche GRNS instrument scientist from the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland. Peplowski led the development of the GRS commissioning activities, in close collaboration with the Psyche science operations team at JPL.
To the untrained eye, the collection of squiggly lines means virtually nothing, but to the multi-institutional team of physicists who spent nine years developing the instrument, those lines are a herald of exciting things to come - for both Psyche and future NASA missions.
"[The data] are showing us that we have a really high-performance instrument, and will allow us to refine calculations about how sensitive we'll be when we get to Psyche," said Lawrence, the Psyche GRS investigation lead, from APL.
Built by APL in partnership with Lawrence Livermore National Laboratory (LLNL) and with significant contributions from Lockheed Martin Advanced Technology Center (ATC), Psyche's GRS will play an important role in the mission's goal to determine whether Psyche - an asteroid 150 miles (240 kilometers) wide - is the fragment of an early planetesimal, or a building block of a planet.
The highlight of the commission measurements, and the key to determining Psyche's composition, are the gamma-ray spectra from the GRS. Like chemical fingerprints, gamma rays released by the interaction of cosmic particles with a planetary surface reveal the elemental composition of that object. Consequently, gamma rays can provide the chemical clues needed to confirm that asteroid Psyche is indeed the metallic remnant of a planetary core from the early solar system.
The Psyche GRS team has built gamma-ray instruments for numerous space missions, including NASA's Near Earth Asteroid Rendezvous (NEAR) mission, which made the first orbital and landed measurements of an asteroid, and NASA's MESSENGER mission to Mercury, both led by APL.
Psyche's GRS incorporates lessons learned from those instruments to advance the state of the art for planetary gamma-ray instrumentation. It employs a new type of cryocooler, developed by Lockheed Martin, to cool the instrument's pure germanium-crystal "heart" to a chilly minus 292 degrees Fahrenheit (minus 180 degrees Celsius). "That change should allow the instrument to last significantly longer than its predecessors," Lawrence said.
"It's the highest-resolution gamma-ray spectrometer that has ever flown in space," said Burks, a physicist at LLNL who helped design and build the gamma-ray sensor at the heart of the Psyche GRS. "The data returned already indicate it will have over twice the resolution of our prior MESSENGER instrument, which shows it will have unparalleled sensitivity for measuring the elemental composition of Psyche."
Those auspicious indications bode well not only for what's to come when Psyche reaches its destination in 2029 but also for the coming decades of space exploration. Two upcoming missions will host similar APL-developed GRS instruments, including the MEGANE instrument on the Japan Aerospace Exploration Agency's Martian Moons eXploration mission, and NASA's APL-led Dragonfly mission to Saturn's largest moon Titan. The Mapping Imaging Spectrometer for Europa (MISE) instrument on NASA's Europa Clipper mission uses the same type of cryocooler as the Psyche mission.
After a two-week process of testing the instrument's performance, the team turned the gamma-ray sensor off on Nov. 27. Other portions of the GRS, including a sensor that measures neutrons and protons, remain on. The team is scheduled to turn on the other half of the GRNS - the neutron spectrometer - in mid-December. "Once the neutron spectrometer is commissioned, we'll transition to collecting valuable measurements of the space environment throughout our roughly 5.5-year-long cruise from Earth to our destination in the asteroid belt," Peplowski noted.
Arizona State University leads the Psyche mission. NASA's Jet Propulsion Laboratory is responsible for the mission's overall management and mission operations. APL, LLNL, Lockheed Martin ATC, the Space Sciences Laboratory at the University of California, Berkeley, and Mirion Technologies, Inc., were significant partners in development of the Psyche GRS.
Quelle: SD