NASA Astronomy Picture of the Day

Feb 9, 2024

When Roses Aren't Red

Not all roses are red of course, but they can still be very pretty. Likewise, the beautiful Rosette Nebula and other star forming regions are often shown in astronomical images with a predominately red hue, in part because the dominant emission in the nebula is from hydrogen atoms. Hydrogen's strongest optical emission line, known as H-alpha, is in the red region of the spectrum. But the beauty of an emission nebula need not be appreciated in red light alone. Other atoms in the nebula are also excited by energetic starlight and produce narrow emission lines as well. In this close-up view of the Rosette Nebula, narrowband images are mapped into broadband colors to show emission from Sulfur atoms in red, Hydrogen in green, and Oxygen in blue. In fact, the scheme of mapping these narrow atomic emission lines (SHO) into the broader colors (RGB) is adopted in many Hubble images of emission nebulae. This image spans about 50 light-years across the center of the Rosette Nebula. The nebula lies some 3,000 light-years away in the constellation Monoceros.

https://apod.nasa.gov/apod/astropix.html?

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NASA Expedition 71 Astronauts to Conduct Research aboard Space Station

FEB 09, 2024

Studies of neurological organoids, plant growth, and shifts in body fluids are among the scientific investigations that NASA astronauts Matthew Dominick, Michael Barratt, Jeanette Epps, and Tracy C. Dyson will help support aboard the International Space Station as part of Expedition 71. The crew members are targeting launch to the space station in February and March.

Here are details on some of the work scheduled during this upcoming expedition aboard the microgravity laboratory:

Modeling Neuroinflammation

Human Brain Organoid Models for Neurodegenerative Disease & Drug Discovery (HBOND) studies the mechanisms behind neuroinflammation, a common feature of neurodegenerative disorders. Researchers create organoids using patient-derived iPSCs (induced pluripotent stem cells) from patients who have Parkinson’s disease and primary progressive multiple sclerosis. The sixth space station organoid investigation funded by the National Stem Cell Foundation, HBOND includes for the first time Alzheimer’s iPSCs and testing of the effects of drugs in development to treat neuroinflammation. Results could help improve diagnostics, provide insights into the effects of aging, accelerate drug discovery, and identify therapeutic targets for patients suffering from neurodegenerative diseases. The organoid models also could provide a way to anticipate how extended spaceflight affects the brain and support development of countermeasures.

Protecting Plants from Spaceflight Stressors

Plants can serve as a source of food and provide other life-support services on long-term missions to the Moon and Mars. The Study on Plant Responses Against the Stresses of Microgravity and High Ultraviolet Radiation in Space (Plant UV-B) examines how stress from microgravity, UV radiation, and the combination of the two affect plants at the molecular, cellular, and whole organism levels. Results could increase understanding of plant growth in space and support improvements in plant cultivation technologies for future missions.

Positive Pressure

Microgravity causes fluids in the body to move toward the head, which can cause changes in eye structure and vision known as Spaceflight Associated Neuro-ocular Syndrome (SANS) and other health problems. Mitigating Headward Fluid Shifts with Veno-constrictive Thigh Cuffs During Spaceflight (Thigh Cuff) examines whether thigh pressure cuffs could provide a simple way to counter this shift of body fluids and help protect astronauts from SANS and other issues on future missions to the Moon and Mars. Thigh cuffs also could help treat or prevent problems for patients with conditions on Earth that can cause fluid accumulation in the body, such as long-term bedrest and diseases.

Incredible Edible Algae

Arthrospira-C (Art-C), an investigation from ESA (European Space Agency) analyzes how the cyanobacterium Limnospira responds to spaceflight conditions and whether it produces the same quantity and quality of oxygen and biomass in space as on Earth. These microalgae, also known as Spirulina, could be used to remove carbon dioxide exhaled by astronauts, which can become toxic in an enclosed spacecraft, and to produce oxygen and fresh food as part of life support systems on future missions. Correct predictions of oxygen and biomass yields are crucial for design of life support systems using bioprocesses. Spirulina also has been shown to have radioprotective properties and eating it could help protect space travelers from cosmic radiation, as well as conserve healthy tissue in patients undergoing radiation treatment on Earth.

https://www.nasa.gov/humans-in-space/nasa-expedition-71-astronauts-to-conduct-research-aboard-space-station/

NASA’s New Experimental Antenna Tracks Deep Space Laser

FEB 08, 2024

An experimental antenna has received both radio frequency and near-infrared laser signals from NASA’s Psyche spacecraft as it travels through deep space. This shows it’s possible for the giant dish antennas of NASA’s Deep Space Network (DSN), which communicate with spacecraft via radio waves, to be retrofitted for optical, or laser, communications.

By packing more data into transmissions, optical communication will enable new space exploration capabilities while supporting the DSN as demand on the network grows.

The 34-meter (112-foot) radio-frequency-optical-hybrid antenna, called Deep Space Station 13, has tracked the downlink laser from NASA’s Deep Space Optical Communications (DSOC) technology demonstration since November 2023. The tech demo’s flight laser transceiver is riding with the agency’s Psyche spacecraft, which launched on Oct. 13, 2023.

The hybrid antenna is located at the DSN’s Goldstone Deep Space Communications Complex, near Barstow, California, and isn’t part of the DSOC experiment. The DSN, DSOC, and Psyche are managed by NASA’s Jet Propulsion Laboratory in Southern California.

“Our hybrid antenna has been able to successfully and reliably lock onto and track the DSOC downlink since shortly after the tech demo launched,” said Amy Smith, DSN deputy manager at JPL. “It also received Psyche’s radio frequency signal, so we have demonstrated synchronous radio and optical frequency deep space communications for the first time.”

In late 2023, the hybrid antenna downlinked data from 20 million miles (32 million kilometers) away at a rate of 15.63 megabits per second – about 40 times faster than radio frequency communications at that distance. On Jan. 1, 2024, the antenna downlinked a team photograph that had been uploaded to DSOC before Psyche’s launch.

In late 2023, the hybrid antenna downlinked data from 20 million miles (32 million kilometers) away at a rate of 15.63 megabits per second – about 40 times faster than radio frequency communications at that distance. On Jan. 1, 2024, the antenna downlinked a team photograph that had been uploaded to DSOC before Psyche’s launch.

In order to detect the laser’s photons (quantum particles of light), seven ultra-precise segmented mirrors were attached to the inside of the hybrid antenna’s curved surface. Resembling the hexagonal mirrors of NASA’s James Webb Space Telescope, these segments mimic the light-collecting aperture of a 3.3-foot (1-meter) aperture telescope. As the laser photons arrive at the antenna, each mirror reflects the photons and precisely redirects them into a high-exposure camera attached to the antenna’s subreflector suspended above the center of the dish.

The laser signal collected by the camera is then transmitted through optical fiber that feeds into a cryogenically cooled semiconducting nanowire single photon detector. Designed and built by JPL’s Microdevices Laboratory, the detector is identical to the one used at Caltech’s Palomar Observatory, in San Diego County, California, which acts as DSOC’s downlink ground station.

“It’s a high-tolerance optical system built on a 34-meter flexible structure,” said Barzia Tehrani, communications ground systems deputy manager and delivery manager for the hybrid antenna at JPL. “We use a system of mirrors, precise sensors, and cameras to actively align and direct laser from deep space into a fiber reaching the detector.”

Tehrani hopes the antenna will be sensitive enough to detect the laser signal sent from Mars at its farthest point from Earth (2 ½ times the distance from the Sun to Earth). Psyche will be at that distance in June on its way to the main asteroid belt between Mars and Jupiter to investigate the metal-rich asteroid Psyche.

The seven-segment reflector on the antenna is a proof of concept for a scaled-up and more powerful version with 64 segments – the equivalent of a 26-foot (8-meter) aperture telescope – that could be used in the future.

DSOC is paving the way for higher-data-rate communications capable of transmitting complex scientific information, video, and high-definition imagery in support of humanity’s next giant leap: sending humans to Mars. The tech demo recently streamed the first ultra-high-definition video from deep space at record-setting bitrates.

Retrofitting radio frequency antennas with optical terminals and constructing purpose-built hybrid antennas could be a solution to the current lack of a dedicated optical ground infrastructure. The DSN has 14 dishes distributed across facilities in California, Madrid, and Canberra, Australia.

https://www.nasa.gov/technology/space-comms/deep-space-network/nasas-new-experimental-antenna-tracks-deep-space-laser/

Nuclear fusion lab sets record for most energy created with single reaction

Feb 9, 2024

Since 1983, scientists have used England's Joint European Torus (JET) to recreate nuclear fusion, the merging of atoms that powers the sun and other stars, in Britain. An effective nuclear fusion setup could give us immense quantities of clean energy.

Now, during the last days of its four-decade-long life, JET has set a new record for the most energy created in a single fusion reaction. JET's new record is the latest milestone in an exciting few years for fusion. With each milestone, fusion scientists inch closer — slowly, very slowly, but steadily — toward constructing a commercial fusion power plant that can plug into the grid.

Using 0.2 milligrams of fuel (about a hundred thousandth of an ounce) JET sustained high fusion power for 5 seconds and created 69 megajoules of energy. That's about enough to power an average home for maybe a few minutes. Neither of these parameters seems Earth-shattering, but they are indeed numbers for fusion scientists to celebrate.

"JET's final fusion experiment is a fitting swansong after all the groundbreaking work that has gone into the project since 1983," UK Minister for Nuclear and Networks, Andrew Bowie, said in a statement. "We are closer to fusion energy than ever before thanks to the international team of scientists and engineers in Oxfordshire."

However, while JET did set a record for raw energy, it did not set a record for yield. That's the ratio of energy produced to the energy that scientists put in to trigger fusion in the first place. JET once held that record, too, but the National Ignition Facility (NIF) in California’s Lawrence Livermore National Laboratory surpassed it in 2022.

In fact, NIF was the first fusion facility in the world to do something that JET could not do: elicit a yield of more than 1, or, in other words, create more energy than scientists put in. As of late 2023, NIF has achieved yields of close to 2.

Tempting as it is to compare the two experiments, doing so directly is difficult. NIF is an example of inertial confinement fusion (ICF). NIF's apparatus relies on blasting a fuel-stuffed capsule with lasers, creating intense X-ray cascades that compress the fuel into fusion. JET, on the other hand, is a tokamak, or a doughnut-shaped container stuffed with superheated plasma. By magnetically sculpting the plasma, a tokamak's operators can ignite fusion.

For JET, this record means that the facility can end its life on a triumphant note. Its operators have already begun the lengthy process of decommissioning the reactor. But JET's end is certainly not the end for tokamak science. JET is a testbed for the International Thermonuclear Experimental Reactor (ITER): a future reactor set to launch in 2025, with an eye of testing tokamak tech for a line of future reactors even farther in the future.

https://www.space.com/nuclear-fusion-lab-record-energy-single-reaction

Collins performs tests of new space station spacesuit

Feb 8, 2024

Collins Aerospace, one of the companies with a NASA award to develop a new generation of spacesuits, has completed a series of tests of that design in a microgravity environment on an aircraft.

The company, which won an Exploration Extravehicular Activity Services, or xEVAS, contract from NASA in 2022, said last week it completed tests called the Crew Capability Assessment. Those tests examined how well a person wearing the suit could perform tasks that an astronaut on a spacewalk outside the International Space Station might do.

Those tests were conducted onboard an aircraft flying parabolic arcs that allows for 15 to 25 seconds of microgravity at a time. That meant breaking down a specific activity “into its most fundamental pieces” that can be done within that time, said Danny Olivas, a former NASA astronaut who is now chief test astronaut at Collins, in an interview.

Examples of those tasks, he said, include entering and exiting an airlock hatch, attaching the suit’s boots to a foot restraint and manipulating connectors. “What we were looking for is to verify the design that we had put forward,” he said. “That design solution does indeed allow for full range of motion through the work envelope that the suit is being built towards.”

Collins planned two days of flights to complete about 20 test objectives, he said, but was able to get them all done in one day. The second day was then used to perform additional engineering evaluations on the suit.

The company is working on a suit intended to replace the decades-old Extravehicular Mobility Unit (EMU) spacesuits currently used on the ISS under a task order Collins won in December 2022. Collins says its design is intended to be less bulky than the EMU and support a wider range of body types.

“My honest opinion is that it is a far more capable suit,” said Olivas, who performed five spacewalks spanning more than 34 hours during two shuttle missions while at NASA. One example is a redesign of the shoulder joint that enables a greater degree of motion compared to the existing EMU, particularly for smaller people.

One example he gave was clipping the boots into the foot restraint. In the old suit, people just getting used to the suit would take 5 to 10 minutes during training in the Neutral Buoyancy Lab (NBL), a large pool used for simulating spacewalks. Olivas said he was able to do in with the new suit within a single 20-second stretch of microgravity on the aircraft.

The next step for the suit is a round of tests in the NBL for longer simulations of spacewalk tasks. Those tests will seek to confirm the suit can perform equal to or better than the EMU on key activities during ISS spacewalks.

While the initial purpose of the suit is to replace the EMU suit on the ISS, Olivas said the company is looking at other applications for it, such as on future commercial space stations that will succeed the ISS.

“We need to understand what the suit can do for a yet-to-be-determined space station,” he said. “Regardless of who gets there first or which system it is, we want to be able to operate in that environment.” He added that Collins has been in discussions with the companies involved in NASA’s Commercial Low Earth Orbit Destinations program that is supporting development of those commercial stations.

Collins is also looking ahead to potential use of the suit on spacewalks at the lunar Gateway and even on the lunar surface. While the other xEVAS awardee, Axiom Space, has the task order for developing a lunar spacesuit, the two companies have “crossover” task orders from NASA so that Axiom can study use of its suit on the ISS and Collins for Artemis missions.

Olivas said the current suit design is 90% to 95% extensible to one that would be used on the lunar surface. “We also have to be thinking about if we take the suit that works great in micro G, let’s plunk it on the moon; now what does that mean?” he said. “We don’t want to design ourselves into a box of only the micro G environment. We really want to look at all of human exploration for the foreseeable future.”

https://spacenews.com/collins-performs-tests-of-new-space-station-spacesuit/