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NASA Astronomy Picture of the Day
April 23, 2024
Contrail Shadow X
What created this giant X in the clouds? It was the shadow of contrails illuminated from below. When airplanes fly, humid engine exhaust may form water droplets that might freeze in Earth's cold upper atmosphere. These persistent streams of water and ice scatter light from the Sun above and so appear bright from below. On rare occasions, though, when the Sun is near the horizon, contrails can be lit from below. These contrails cast long shadows upwards, shadows that usually go unseen unless there is a high cloud deck. But that was just the case over Istanbul, Türkiye, earlier this month. Contrails occur all over planet Earth and, generally, warm the Earth when the trap infrared light but cool the Earth when they efficiently reflect sunlight. The image was taken by a surprised photographer in the morning on the way to work.
https://apod.nasa.gov/apod/astropix.html?
NASA’s Voyager 1 Resumes Sending Engineering Updates to Earth
April 22, 2024
For the first time since November, NASA’s Voyager 1 spacecraft is returning usable data about the health and status of its onboard engineering systems. The next step is to enable the spacecraft to begin returning science data again. The probe and its twin, Voyager 2, are the only spacecraft to ever fly in interstellar space (the space between stars).
Voyager 1 stopped sending readable science and engineering data back to Earth on Nov. 14, 2023, even though mission controllers could tell the spacecraft was still receiving their commands and otherwise operating normally. In March, the Voyager engineering team at NASA’s Jet Propulsion Laboratory in Southern California confirmed that the issue was tied to one of the spacecraft’s three onboard computers, called the flight data subsystem (FDS). The FDS is responsible for packaging the science and engineering data before it’s sent to Earth.
The team discovered that a single chip responsible for storing a portion of the FDS memory — including some of the FDS computer’s software code — isn’t working. The loss of that code rendered the science and engineering data unusable. Unable to repair the chip, the team decided to place the affected code elsewhere in the FDS memory. But no single location is large enough to hold the section of code in its entirety.
So they devised a plan to divide the affected code into sections and store those sections in different places in the FDS. To make this plan work, they also needed to adjust those code sections to ensure, for example, that they all still function as a whole. Any references to the location of that code in other parts of the FDS memory needed to be updated as well.
The team started by singling out the code responsible for packaging the spacecraft’s engineering data. They sent it to its new location in the FDS memory on April 18. A radio signal takes about 22 ½ hours to reach Voyager 1, which is over 15 billion miles (24 billion kilometers) from Earth, and another 22 ½ hours for a signal to come back to Earth. When the mission flight team heard back from the spacecraft on April 20, they saw that the modification worked: For the first time in five months, they have been able to check the health and status of the spacecraft.
During the coming weeks, the team will relocate and adjust the other affected portions of the FDS software. These include the portions that will start returning science data.
Voyager 2 continues to operate normally. Launched over 46 years ago, the twin Voyager spacecraft are the longest-running and most distant spacecraft in history. Before the start of their interstellar exploration, both probes flew by Saturn and Jupiter, and Voyager 2 flew by Uranus and Neptune.
https://www.jpl.nasa.gov/news/nasas-voyager-1-resumes-sending-engineering-updates-to-earth
NASA Astronaut to Inspire Artemis Generation in Boston
APR 22, 2024
NASA astronaut Stephen Bowen, along with representatives from NASA and the International Space Station National Laboratory, will visit Boston on Wednesday, April 24, and Thursday, April 25, as part of the agency’s Destination Station to highlight research opportunities aboard the station.
Destination Station was created to educate the public and engage prospective researchers about the benefits, capabilities, and opportunities to use the space station. The space station has been continuously inhabited for more than 23 years, enabling more than 5,000 researchers to conduct more than 3,500 innovative experiments in the areas of biology and biotechnology, human health, space and physical science, and technology.
Throughout the week, NASA and the ISS National Lab will meet with a variety of academic institutions, business incubators, and private-sector companies with ties to the Boston community. During the visits, Bowen will provide perspectives on living and working in space.
Media who wish interview Bowen during the outreach events in Boston, should contact Kara Slaughter at kara.c.slaughter@nasa.gov or 281-483-5111.
Bowen was the first submarine officer selected to be a NASA astronaut. He most recently served as commander of NASA’s SpaceX Crew-6 mission to the station where he was part of a six-month research mission, Expedition 69. He is a veteran of three space shuttle flights to the station, including STS-126, STS-132, and STS-133. Bowen has logged a total of 227 days in space and conducted 10 extravehicular activities in his career. His 10 spacewalks make him one of five humans who have conducted that many spacewalks and he is third on the all-time list for most cumulative spacewalking time. Bowen and the crews of Expedition 68 and 69 conducted more than 200 science experiments including tissue chip research, bioprinting human cells and tissues in space, and studying antibodies in microgravity. Bowen is a Massachusetts native and earned his bachelor’s degree from the United States Naval Academy in Annapolis, Maryland, and his master’s degree from the Massachusetts Institute of Technology in Cambridge.
Over the years, NASA’s Destination Station has led to research collaborations aboard the orbiting laboratory with a variety of academic and commercial companies. This visit also is a prelude to the 13th annual International Space Station Research and Development Conference at the Boston Marriott Copley Square from July 29 – Aug. 1, 2024.
https://www.nasa.gov/news-release/nasa-astronaut-to-inspire-artemis-generation-in-boston/
Why is Methane Seeping on Mars? NASA Scientists Have New Ideas
APR 22, 2024
The most surprising revelation from NASA’s Curiosity Mars Rover — that methane is seeping from the surface of Gale Crater — has scientists scratching their heads.
Living creatures produce most of the methane on Earth. But scientists haven’t found convincing signs of current or ancient life on Mars, and thus didn’t expect to find methane there. Yet, the portable chemistry lab aboard Curiosity, known as SAM, or Sample Analysis at Mars, has continually sniffed out traces of the gas near the surface of Gale Crater, the only place on the surface of Mars where methane has been detected thus far. Its likely source, scientists assume, are geological mechanisms that involve water and rocks deep underground.
If that were the whole story, things would be easy. However, SAM has found that methane behaves in unexpected ways in Gale Crater. It appears at night and disappears during the day. It fluctuates seasonally, and sometimes spikes to levels 40 times higher than usual. Surprisingly, the methane also isn’t accumulating in the atmosphere: ESA’s (the European Space Agency) ExoMars Trace Gas Orbiter, sent to Mars specifically to study the gas in the atmosphere, has detected no methane.
“It’s a story with a lot of plot twists,” said Ashwin Vasavada, Curiosity’s project scientist at NASA’s Jet Propulsion Laboratory in Southern California, which leads Curiosity’s mission.
Methane keeps Mars scientists busy with lab work and computer modeling projects that aim to explain why the gas behaves strangely and is detected only in Gale Crater. A NASA research group recently shared an interesting proposal.
Reporting in a March paper in the Journal of Geophysical Research: Planets, the group suggested that methane — no matter how it’s produced — could be sealed under solidified salt that might form in Martian regolith, which is “soil” made of broken rock and dust. When temperature rises during warmer seasons or times of day, weakening the seal, the methane could seep out.
Led by Alexander Pavlov, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, the researchers suggest the gas also can erupt in puffs when seals crack under the pressure of, say, a rover the size of a small SUV driving over it. The team’s hypothesis may help explain why methane is detected only in Gale Crater, Pavlov said, given that’s it’s one of two places on Mars where a robot is roving and drilling the surface. (The other is Jezero Crater, where NASA’s Perseverance rover is working, though that rover doesn't have a methane-detecting instrument.)
Pavlov traces the origin of this hypothesis to an unrelated experiment he led in 2017, which involved growing microorganisms in a simulated Martian permafrost (frozen soil) infused with salt, as much of Martian permafrost is.
Pavlov and his colleagues tested whether bacteria known as halophiles, which live in saltwater lakes and other salt-rich environments on Earth, could thrive in similar conditions on Mars.
The microbe-growing results proved inconclusive, he said, but the researchers noticed something unexpected: The top layer of soil formed a salt crust as salty ice sublimated, turning from a solid to a gas and leaving the salt behind.
“We didn’t think much of it at the moment,” Pavlov said, but he remembered the soil crust in 2019, when SAM’s tunable laser spectrometer detected a methane burst no one could explain.
“That’s when it clicked in my mind,” Pavlov said. And that’s when he and a team began testing the conditions that could form and crack hardened salt seals.
Pavlov’s team tested five samples of permafrost infused with varying concentrations of a salt called perchlorate that’s widespread on Mars. (There’s likely no permafrost in Gale Crater today, but the seals could have formed long ago when Gale was colder and icier.) The scientists exposed each sample to different temperatures and air pressure inside a Mars simulation chamber at NASA Goddard.
Periodically, Pavlov’s team injected neon, a methane analog, underneath the soil sample and measured the gas pressure below and above it. Higher pressure beneath the sample implied the gas was trapped. Ultimately, a seal formed under Mars-like conditions within three to 13 days only in samples with 5% to 10% perchlorate concentration.
That’s a much higher salt concentration than Curiosity has measured in Gale Crater. But regolith there is rich in a different type of salt minerals called sulfates, which Pavlov’s team wants to test next to see if they can also form seals.
https://science.nasa.gov/solar-system/planets/mars/why-is-methane-seeping-on-mars-nasa-scientists-have-new-ideas/
NASA Sets Coverage of Roscosmos Spacewalk Outside Space Station
APR 22, 2024
NASA will provide live coverage, beginning at 10:30 a.m. EDT Thursday, April 25, as two Roscosmos cosmonauts conduct a spacewalk outside the International Space Station. The spacewalk is expected to begin at 10:55 a.m. and could last up to seven hours.
NASA will stream the spacewalk on NASA+, NASA Television, the NASA app, YouTube, and the agency’s website. Learn how to stream NASA TV through a variety of platforms including social media.
Expedition 71 crewmates Oleg Kononenko and Nikolai Chub will venture outside the station’s Poisk airlock to complete the deployment of one panel on a synthetic radar system on the Nauka module.The two cosmonauts will also install equipment and experiments on the Poisk module to analyze the level of corrosion on station surfaces and modules.
The spacewalk will be the 270th in support of space station, and will be the seventh for Kononenko, who will wear the Orlan spacesuit with the red stripes, and the second for Chub, who will wear the spacesuit with the blue stripes.
https://www.nasa.gov/news-release/nasa-sets-coverage-of-roscosmos-spacewalk-outside-space-station-2/
Explore the Universe with the First E-Book from NASA’s Fermi
APR 23, 2024
To commemorate a milestone anniversary for NASA’s Fermi spacecraft, the mission team has published an e-book called “Our High-Energy Universe: 15 Years with the Fermi Gamma-ray Space Telescope.”
Readers can download the e-book in PDF and EPUB formats. The e-book is aimed at general audiences with an interest in space.
Launched on June 11, 2008, Fermi detects gamma rays, the highest-energy form of light, from Earth’s atmosphere to far-flung galaxies and cosmic phenomena in between. Its research has uncovered details on topics ranging from solar flares to star formation and the mysteries at the center of our Milky Way.
Through images, fun facts, and launch-day memories, the e-book tells Fermi’s story from conceptualization to launch and recounts some of the mission’s groundbreaking discoveries. By delving into high-energy astrophysics topics like gamma-ray bursts and blazars, readers can explore Fermi’s universe and what questions remain open for investigation in its next chapter.
Fermi was originally called the Gamma-ray Large Area Space Telescope but was renamed after Italian physicist Enrico Fermi in August 2008.
“Enrico Fermi’s science has been important for understanding the sources that the Fermi telescope sees,” said Elizabeth Hays, the mission’s project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The gamma-ray sky is powered by particle acceleration mechanisms he theorized about.”
The satellite has two gamma-ray detectors: the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM).
The LAT observes a fifth of the gamma-ray sky at any time, detecting high-energy light with energies ranging from 20 million to over 300 billion electron volts. (The energy of visible light is 2 to 3 electron volts.) The GBM views about 70% of the sky at a time at lower energies, searching for brief flashes of gamma-ray light.
The result of this carefully crafted duo is the most sensitive gamma-ray observatory in orbit, equipped to study the universe’s highest-energy phenomena near and far.
By peering through Fermi’s gamma-ray eyes, we can better understand our solar system. Within its first eight years of operation, Fermi detected gamma-ray emissions from 40 solar flares — bursts of energy from the Sun. Some even originated on the Sun’s far side, allowing scientists to analyze how charged particles fired by solar flares can arc from one side of the Sun to produce gamma rays on the other.
In studying our Milky Way, Fermi found two lobes of high-energy gamma rays — called the Fermi Bubbles — extending above and below the galaxy’s center. Each bubble stands 25,000 light-years tall. Astronomers think the bubbles formed following an ancient burst of activity from the Milky Way’s central supermassive black hole.
Fermi helps scientists understand black holes in other galaxies, too.
“As a black hole forms, either from the death of a massive star or the collision of two neutron stars, it creates a brief flash of light called a gamma-ray burst,” said Judith Racusin, Fermi’s deputy project scientist at Goddard. “Fermi detects about one burst a day and has helped revolutionize our understanding of these phenomena.”
Even after 15 years of accomplishments, however, many mysteries remain for Fermi to tackle. One of the telescope’s ongoing objectives is to study the composition of dark matter — the mysterious substance that makes up about 25% of the universe.
Because dark matter doesn’t reflect, absorb, or emit light, scientists remain unsure of its composition. One popular theory suggests, though, that dark matter particles create gamma rays when they interact. If Fermi can spot this high-energy signature, it might help scientists learn more about dark matter’s makeup.
If there’s one thing Fermi has taught us, it’s to expect the unexpected. Gamma-ray research has yielded unprecedented breakthroughs in our understanding of the Milky Way’s central black hole, our flaring Sun, and merging neutron stars. As much as we anticipate the next gamma-ray revelation, only time will tell what exactly Fermi has in store.
Fermi is an astrophysics and particle physics partnership managed by Goddard. Fermi was developed in collaboration with the U.S. Department of Energy, with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden, and the United States.
https://science.nasa.gov/missions/fermi/explore-the-universe-with-the-first-e-book-from-nasas-fermi/
Five future astronauts certified from European Space Agency's 2022 graduating class
April 22, 2024
Six new recruits of the European Space Agency on Monday got to be the latest round of fully qualified astronauts now eligible for space missions, including a woman from Australia.
At a ceremony near Cologne in Germany's state of North Rhine-Westphalia, the five European and one Australian astronaut recruits got their certifications to mark their transition to be fully qualified astronauts now eligible for space missions.
Sophie Adenot of France, Pablo Álvarez Fernández of Spain, Rosemary Coogan from Britain, Raphaël Liégeois of Belgium, and Marco Sieber of Switzerland joined Australian Space Agency candidate Katherine Bennell-Pegg on track to be Australia's first woman in space who wrapped-up their year-long basic training culminating in Monday's ceremony.
They were picked from a "remarkable" pool of 22,500 astronaut applicants across Europe. The ESA astronaut class of November 2022 had 17 individuals which included the five astronaut candidates, and 12 members in the European astronaut reserve.
Their training begin April of last year at their arrival to the European Astronaut Center near Cologne, where they took part in training programs that included spacecraft systems, spacewalks, flight engineering, robotics, life support systems, survival, and medical training.
Last Wednesday ahead of Monday's ceremony, the ESA Director General took note of how in 2020 the agency had for the first time since 2008, "decided to open a new call for a Europe-wide astronaut selection."
"This decision was crucial to preserve European knowhow for training astronauts in Europe – a key capacity for our future in space exploration," said Josef Aschbacher.
On Monday, Aschbacher congratulated the new class by noting it now brings the number of ESA astronauts to a total of 11 from eight European countries. During the ceremony, he acknowledged it was "a challenging year" and said it was "a large effort."
"Thanks to this enlarged family, we are ensuring both our long-term participation in key programs," he said on social medial about the Artemis program and the ISS.
It was called "A great day for Europe in space" earlier on Monday by Anne-Sophie Bradelle, ESA's chief of communications.
Now that the new set of astronauts have been certified, they will begin steps toward their first missions on the International Space Station or other space trips although it's currently unclear when that will be but plans are in the works.
But Aschbacher said their first mission will not be before the year 2026.
Fellow ESA astronaut Matthias Maurer took to social media Monday morning to congratulate his new colleagues.
"A new chapter of European space exploration unfolds, heralding a fresh era for" the European Space Agency, he said on X.
"Their incredible teamwork showcases the possibilities of EAC as Europe's premier astronaut training hub," wrote Maurer, who recently completed a 175-day mission on the International Space Station.
https://www.msn.com/en-us/news/technology/five-future-astronauts-certified-from-european-space-agency-s-2022-graduating-class/ar-AA1nsONr
Researchers detect a new molecule in space
APRIL 23, 2024
New research from the group of MIT Professor Brett McGuire has revealed the presence of a previously unknown molecule in space. The team's open-access paper, "Rotational Spectrum and First Interstellar Detection of 2-Methoxyethanol Using ALMA Observations of NGC 6334I," was published in the April 12 issue of The Astrophysical Journal Letters.
Zachary T.P. Fried, a graduate student in the McGuire group and the lead author of the publication, worked to assemble a puzzle comprised of pieces collected from across the globe, extending beyond MIT to France, Florida, Virginia, and Copenhagen, to achieve this exciting discovery.
"Our group tries to understand what molecules are present in regions of space where stars and solar systems will eventually take shape," explains Fried. "This allows us to piece together how chemistry evolves alongside the process of star and planet formation. We do this by looking at the rotational spectra of molecules, the unique patterns of light they give off as they tumble end-over-end in space.
"These patterns are fingerprints (barcodes) for molecules. To detect new molecules in space, we first must have an idea of what molecule we want to look for, then we can record its spectrum in the lab here on Earth, and then finally we look for that spectrum in space using telescopes."
Searching for molecules in space
The McGuire Group has recently begun to utilize machine learning to suggest good target molecules to search for. In 2023, one of these machine learning models suggested the researchers target a molecule known as 2-methoxyethanol.
"There are a number of 'methoxy' molecules in space, like dimethyl ether, methoxymethanol, ethyl methyl ether, and methyl formate, but 2-methoxyethanol would be the largest and most complex ever seen," says Fried.
To detect this molecule using radio telescope observations, the group first needed to measure and analyze its rotational spectrum on Earth. The researchers combined experiments from the University of Lille (Lille, France), the New College of Florida (Sarasota, Florida), and the McGuire lab at MIT to measure this spectrum over a broadband region of frequencies ranging from the microwave to sub-millimeter wave regimes (approximately 8 to 500 gigahertz).
The data gleaned from these measurements permitted a search for the molecule using Atacama Large Millimeter/submillimeter Array (ALMA) observations toward two separate star-forming regions: NGC 6334I and IRAS 16293-2422B. Members of the McGuire group analyzed these telescope observations alongside researchers at the National Radio Astronomy Observatory (Charlottesville, Virginia) and the University of Copenhagen, Denmark.
"Ultimately, we observed 25 rotational lines of 2-methoxyethanol that lined up with the molecular signal observed toward NGC 6334I (the barcode matched), thus resulting in a secure detection of 2-methoxyethanol in this source," says Fried. "This allowed us to then derive physical parameters of the molecule toward NGC 6334I, such as its abundance and excitation temperature. It also enabled an investigation of the possible chemical formation pathways from known interstellar precursors."
Looking forward
Molecular discoveries like this one help the researchers to better understand the development of molecular complexity in space during the star formation process. 2-methoxyethanol, which contains 13 atoms, is quite large for interstellar standards—as of 2021, only six species larger than 13 atoms were detected outside the solar system, many by McGuire's group, and all of them existing as ringed structures.
"Continued observations of large molecules and subsequent derivations of their abundances allows us to advance our knowledge of how efficiently large molecules can form and by which specific reactions they may be produced," says Fried.
"Additionally, since we detected this molecule in NGC 6334I but not in IRAS 16293-2422B, we were presented with a unique opportunity to look into how the differing physical conditions of these two sources may be affecting the chemistry that can occur."
https://phys.org/news/2024-04-molecule-space.html