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Life on other planets might not look like any beings we’re used to on Earth. It may even be unrecognizable at first to scientists searching for it. Credit: William Hand

Topics: Astrobiology, Astronomy, Astrophysics, Planetary Science, SETI, Space Exploration

Sarah Stewart Johnson was a college sophomore when she first stood atop Hawaii’s Mauna Kea volcano. Its dried lava surface differed from the eroded, tree-draped mountains of her home state of Kentucky. Johnson wandered away from the other young researchers she was with and toward a distant ridge of the 13,800-foot summit. Looking down, she turned over a rock with the toe of her boot. To her surprise, a tiny fern lived underneath it, sprouting from ash and cinder cones. “It felt like it stood for all of us, huddled under that rock, existing against the odds,” Johnson says.

Her true epiphany, though, wasn’t about the hardiness of life on Earth or the hardships of being human: It was about aliens. Even if a landscape seemed strange and harsh from a human perspective, other kinds of life might find it quite comfortable. The thought opened up the cosmic real estate and the variety of life she imagined might be beyond Earth’s atmosphere. “It was on that trip that the idea of looking for life in the universe began to make sense to me,” Johnson says.

Later, Johnson became a professional at looking. As an astronomy postdoc at Harvard University in the late 2000s and early 2010s, she investigated how astronomers might use genetic sequencing—detecting and identifying DNA and RNA—to find evidence of aliens. Johnson found the work exciting (the future alien genome project!), but it also made her wonder: What if extraterrestrial life didn’t have DNA, RNA, or other nucleic acids? What if their cells got instructions in some other biochemical way?

As an outlet for heretical thoughts like this, Johnson started writing in style too lyrical and philosophical for scientific journals. Her typed musings would later turn into the 2020 popular science book The Sirens of Mars. Inside its pages, she probed the idea that other planets were truly other. So their inhabitants might be very different, at a fundamental and chemical level, from anything in this world. “Even places that seem familiar—like Mars, a place that we think we know intimately—can completely throw us for a loop,” she says. “What if that’s the life case?”

The Search for Extraterrestrial Life as We Don’t Know It, Sarah Scoles, Scientific American

An Orbitrap cell. Credit: Ricardo Arevalo

Topics: Astrobiology, Astronautics, Biology, Laser, NASA, Planetary Science, Space Exploration

As space missions delve deeper into the outer solar system, the need for more compact, resource-conserving, and accurate analytical tools have become increasingly critical—especially as the hunt for extraterrestrial life and habitable planets or moons continues.

A University of Maryland–led team developed a new instrument specifically tailored to the needs of NASA space missions. Their mini laser-sourced analyzer is significantly smaller and more resource efficient than its predecessors—all without compromising the quality of its ability to analyze planetary material samples and potential biological activity onsite. The team's paper on this new device was published in the journal Nature Astronomy on January 16, 2023.

Weighing only about 17 pounds, the instrument is a physically scaled-down combination of two important tools for detecting signs of life and identifying compositions of materials: a pulsed ultraviolet laser that removes small amounts of material from a planetary sample and an Orbitrap analyzer that delivers high-resolution data about the chemistry of the examined materials.

"The Orbitrap was originally built for commercial use," explained Ricardo Arevalo, lead author of the paper and an associate professor of geology at UMD. "You can find them in the labs of pharmaceutical, medical and proteomic industries. The one in my own lab is just under 400 pounds, so they're quite large, and it took us eight years to make a prototype that could be used efficiently in space—significantly smaller and less resource-intensive but still capable of cutting-edge science."

The team's new gadget shrinks down the original Orbitrap while pairing it with laser desorption mass spectrometry (LDMS)—techniques that have yet to be applied in an extraterrestrial planetary environment. The new device boasts the same benefits as its larger predecessors but is streamlined for space exploration and onsite planetary material analysis, according to Arevalo.

Small laser device can help detect signs of life on other planets, University of Maryland, Phys.org.

An artist’s concept of New Horizons during the spacecraft’s planned encounter with Pluto and its moon Charon. The craft’s miniature cameras, radio science experiments, ultraviolet and infrared spectrometers, and space plasma experiments would characterize the global geology and geomorphology of Pluto and Charon, map their surface compositions and temperatures, and examine Pluto’s atmosphere in detail. Credit: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute (JHUAPL/SwRI)

Topics: Astronomy, Astrophysics, NASA, Planetary Science, Space Exploration

Only two spacecraft have ever left our solar system and lived to tell the tale. In 2012 and 2019, NASA’s Voyager 1 and 2 spacecraft respectively broke through the heliopause, the boundary at which our sun’s sphere of influence gives way to the interstellar medium. They have sent back remarkable riches from this distant location, humanity’s first foray into the limitless bounds beyond our solar system’s edge. Hot pursuit is a far more advanced vehicle, sporting improved instruments, updated optics, and even a means to sample the interstellar medium itself. New Horizons was launched from Earth in 2006 on a mission to visit Pluto, arriving in 2015 and revealing incredible details during its all-too-brief flyby. The spacecraft has continued its cruise toward interstellar frontiers ever since. It has now begun its second extended mission. It is soon set to wake up from a deep hibernation, opening a wealth of new scientific opportunities in the outer solar system. “It takes a long time to get to where our spacecraft is,” says Alice Bowman, mission operations manager for New Horizons at the Johns Hopkins University Applied Physics Laboratory (JHUAPL) in Maryland. “When you have a spacecraft that is out in that part of the solar system, it is a huge asset to the scientific community. There are so many unique things that a spacecraft that is out that far can do. We definitely want to take advantage of that.”

For New Horizons, those “unique things” include unprecedented studies of the planets Uranus and Neptune, sampling of the local dust, studies of the background light in the universe, and more. The sum total will be a new phase of the mission that is “really unique and interdisciplinary in nature,” says Alan Stern, the lead on the mission at the Southwest Research Institute (SwRI) in Texas. In October, this two-year second extended mission officially began, but in 2023 it will pick up the pace as the spacecraft exits hibernation and begins its scientific program in earnest. “There were lots of good ideas for how to do things in astrophysics, heliophysics, and planetary science,” Stern says. “We took the very best of those.” There is even the tantalizing possibility of visiting another object in the Kuiper Belt, the region of asteroids and icy objects that lurks beyond Neptune, in which New Horizons has already visited one object—Arrokoth in 2019—after its Pluto encounter. Even without such a possibility, there was more than enough reason for NASA to extend the mission. “New Horizons is at a unique location in the solar system with an amazing suite of functioning instruments on board,” says Becky McCauley Rench, New Horizons program scientist at NASA Headquarters in Washington, D.C. “[It] can provide valuable insights to the heliosphere and the solar wind, astronomical observations of the cosmic background radiation, and valuable data about Uranus and Neptune that can be applied to our knowledge about ice giant planets.”

NASA’s Pluto Spacecraft Begins New Mission at the Solar System’s Edge, Jonathan O'Callaghan, Scientific American

Credit: NASA, ESA, CSA, and Jupiter ERS Team; Image processing by Ricardo Hueso/UPV/EHU and Judy Schmidt

Topics: Astronomy, Astrophysics, Planetary Science, Space Exploration

Jupiter's rings, its moons Amalthea (the bright point at left), Adrastea (the faint dot at the left tip of rings), and even background galaxies are visible in this image from JWST's NIRCam instrument. Whiter areas on the planet represent regions with more cloud cover, which reflects sunlight, especially Jupiter's famous Great Red Spot; darker spots have fewer clouds. Perhaps the most stunning feature is the blue glow of the planet's auroras at the north and south poles. This light shows results when high-energy particles streaming off the sun hit atoms in Jupiter's atmosphere. Auroras are found on any planet with an atmosphere and a magnetic field, which steers the sun's particles to the poles; besides Earth and Jupiter, telescopes have seen auroras on Saturn, Uranus, and Neptune.

The Best of JWST’s Cosmic Portraits, Clara Moskowitz, Scientific American

A view of Saturn from NASA's Hubble Space Telescope captures details of its ring system and atmospheric details on June 20, 2019. NASA, ESA, A. Simon (GSFC), M.H. Wong (University of California, Berkeley), and the OPAL Team/Handout via REUTERS

Topics: Astronomy, Astrophysics, NASA, Planetary Science

WASHINGTON, Sept 15 (Reuters) - Call it the case of the missing moon.

Scientists using data obtained by NASA's Cassini spacecraft and computer simulations said on Thursday the destruction of a large moon that strayed too close to Saturn would account both for the birth of the gas giant planet's magnificent rings and its unusual orbital tilt of about 27 degrees.

The researchers named this hypothesized moon Chrysalis and said it may have been torn apart by tidal forces from Saturn's gravitational pull perhaps 160 million years ago - relatively recent compared to the date of the planet's formation more than 4.5 billion years ago.

About 99% of the Chrysalis wreckage appears to have plunged into Saturn's atmosphere while the remaining 1% stayed in orbit around the planet and eventually formed the large ring system that is one of the wonders of our solar system, the researchers said. They chose the name Chrysalis for the moon because it refers to a butterfly's pupal stage before it transforms into its glorious adult form.

"As a butterfly emerges from a chrysalis, the rings of Saturn emerged from the primordial satellite Chrysalis," said Jack Wisdom, a professor of planetary science at the Massachusetts Institute of Technology and lead author of the study published in the journal Science.

Violent death of moon Chrysalis may have spawned Saturn's rings, Will Dunham, Reuters Science

Image source: The Roddenberry Foundation link below

Topics: Planetary Science, Space Exploration, Spaceflight, Star Trek

NASA is helping the legacy of inspiration, hope, and diversity fostered by the creator of Star Trek to live long and prosper. The agency will observe the late Gene Roddenberry’s 100th birthday with a special program called, Celebrating Gene Roddenberry: Star Trek's Bridge and NASA – a panel discussion airing on NASA Television, the agency’s website, the NASA App, and NASA social media at 2 p.m. EDT Thursday, Aug. 19.

The program includes introductory remarks by NASA Administrator Bill Nelson followed by a panel discussion moderated by Rod Roddenberry, son of Gene Roddenberry. Special guest George Takei, a Star Trek actor, and activist will participate in the question-and-answer session.

Coinciding with the program, NASA will broadcast into space a 1976 recording of Gene Roddenberry's remarks on diversity and inclusion through the agency’s Deep Space Network of radio antennas. NASA also is inviting people on social media to join in celebrating Roddenberry’s 100th birthday on Thursday by posting a Vulcan salute selfie with the hashtag #Roddenberry100.

The Roddenberry Foundation Centennial Celebration

NASA

Image Source: Link below

Topics: Astrophysics, Planetary Science, SETI, Space Exploration

Even as a child, before he devoted his life to the search for extraterrestrial life, Frank Drake wondered whether Earth was alone in its ability to harbor life. He wasn’t the first or the only one to wonder. There’s a reason so many are fascinated by the question: Its answer helps reveal humankind’s place in the cosmos.

Drake’s musings inspired him to pursue astronomy, serving as director of the Arecibo Observatory in Puerto Rico and president of the SETI Institute — which, as the acronym suggests, is devoted to the Search for Extraterrestrial Intelligence, and exploring the possibilities of life elsewhere in the universe. Drake is perhaps most famous for his eponymous equation — an estimate of how many alien civilizations might exist in our galaxy. Presented in 1961, the equation is generally considered as the start of a new era of searches for extraterrestrial intelligence.

But decades after the invention of that famous equation, Drake has conceded that his estimates were overly conservative. Among the too-moderate assumptions was that a potentially inhabited other world must be orbiting a star — overlooking the possibility of life on rogue planets.

Sometimes called “nomads of the galaxy” or “orphan planets,” these cold, dark worlds careen through space with no home, no solar system, no sun to orbit. Long ago, they formed around a star but were flung out, abandoned by their parents. There are billions of rogue planets — astronomers estimate there could be at least one for every star — wandering the galaxy.

It may seem futile to search for life in such cold, desolate environments, but over the last two decades, astronomers have come up with a number of possible scenarios that would make life possible on a planet without a star.

Can Life Exist on a Rogue Planet? Katie McCormick, Discovery Magazine

A global view of Ganymede, based on data gathered by NASA’s Voyager 1, Voyager 2, and Galileo spacecraft. Credit: USGS Astrogeology Science Center, Wheaton, NASA and JPL-Caltech

Topics: Astronomy, Astrophysics, NASA, Planetary Science, Space Exploration

Ganymede, get ready for your close-up.

No probe has gotten a good view of Jupiter’s largest moon since 2000 when NASA’s Galileo spacecraft swung past the strange world, which is the largest moon in the whole solar system. But on Monday (June 7),  at 1:35 p.m. EDT (1735 GMT), NASA’s Juno spacecraft will skim just 645 miles (1,038 kilometers) above Ganymede’s surface, gathering a host of observations as it does so.

“Juno carries a suite of sensitive instruments capable of seeing Ganymede in ways never before possible," principal investigator Scott Bolton, a space scientist at the Southwest Research Institute in San Antonio, said in a NASA statement. “By flying so close, we will bring the exploration of Ganymede into the 21st century.”

Ganymede is a fascinating world for scientists. Despite its status as a moon, it’s larger than the tiny planet Mercury and is the only moon to sport a magnetic field, a bubble of charged particles dubbed a magnetosphere. Until now, the only spacecraft to get a good look at Ganymede were NASA’s twin Voyager probes in 1979 and the Galileo spacecraft, which flew past the moon in 2000.

NASA’s Juno Set for Close Encounter with Jupiter’s Moon Ganymede, Meghan Bartels, SPACE.com, Scientific American

Topics: Biology, Planetary Science, Research, Tardigrades

They can survive temperatures close to absolute zero. They can withstand heat beyond the boiling point of water. They can shrug off the vacuum of space and doses of radiation that would be lethal to humans. Now, researchers have subjected tardigrades, microscopic creatures affectionately known as water bears, to impacts as fast as a flying bullet. And the animals survive them, too—but only up to a point. The test places new limits on their ability to survive impacts in space—and potentially seed life on other planets.

The research was inspired by a 2019 Israeli mission called Beresheet, which attempted to land on the Moon. The probe infamously included tardigrades on board that mission managers had not disclosed to the public, and the lander crashed with its passengers in tow, raising concerns about contamination. “I was very curious,” says Alejandra Traspas, a Ph.D. student at Queen Mary University of London who led the study. “I wanted to know if they were alive.”

Traspas and her supervisor, Mark Burchell, a planetary scientist at the University of Kent, wanted to find out whether tardigrades could survive such an impact—and they wanted to conduct their experiment ethically. So after feeding about 20 tardigrades moss and mineral water, they put them into hibernation, a so-called “tun” state in which their metabolism decreases to 0.1% of their normal activity, by freezing them for 48 hours.</em>

They then placed two to four at a time in a hollow nylon bullet and fired them at increasing speeds using a two-stage light gas gun, a tool in physics experiments that can achieve muzzle velocities far higher than any conventional gun. When shooting the bullets into a sand target several meters away, the researchers found the creatures could survive impacts up to about 900 meters per second (or about 3000 kilometers per hour), and momentary shock pressures up to a limit of 1.14 gigapascals (GPa), they report this month in Astrobiology. “Above [those speeds], they just mush,” Traspas says.</em>

Hardy water bears survive bullet impacts—up to a point, Jonathan O'Callaghan, Science Magazine

In this illustration, NASA's Ingenuity Mars Helicopter stands on the Red Planet's surface as NASA's Perseverance rover (partially visible on the left) rolls away.Credits: NASA/JPL-Caltech

Topics: Mars, NASA, Planetary Science, Space Exploration, Spaceflight

"High Flight" by John Gillespie Magee, Jr.

Ingenuity, a technology experiment, is preparing to attempt the first powered, controlled flight on the Red Planet.

When NASA’s Perseverance rover lands on Mars on Feb. 18, 2021, it will be carrying a small but mighty passenger: Ingenuity, the Mars Helicopter.

The helicopter, which weighs about 4 pounds (1.8 kilograms) on Earth and has a fuselage about the size of a tissue box, started out six years ago as an implausible prospect. Engineers at NASA’s Jet Propulsion Laboratory in Southern California knew it was theoretically possible to fly in Mars’ thin atmosphere, but no one was sure whether they could build a vehicle powerful enough to fly, communicate, and survive autonomously with the extreme restrictions on its mass.

Then the team had to prove in Earthbound tests that it could fly in a Mars-like environment. Now that they’ve checked off those objectives, the team is preparing to test Ingenuity in the actual environment of Mars.

“Our Mars Helicopter team has been doing things that have never been done before – that no one at the outset could be sure could even be done,” said MiMi Aung, the Ingenuity project manager at JPL “We faced many challenges along the way that could have stopped us in our tracks. We are thrilled that we are now so close to demonstrating – on Mars – what Ingenuity can really do.”

Ingenuity survived the intense vibrations of launch on July 30, 2020, and has passed its health checks as it waits to plunge with Perseverance through the Martian atmosphere. But the helicopter won’t attempt its first flight for more than a month after landing: Engineers for the rover and helicopter need time to make sure both robots are ready.

6 Things to Know About NASA’s Mars Helicopter on Its Way to Mars