Should we leave space exploration to robots — or prioritize human spaceflight, making us a multiplanetary species?

Harvard professor Robin Wordsworth, who's researched the evolution and habitability of terrestrial-type planets, shares his thoughts: In space, as on Earth, industrial structures degrade with time, and a truly sustainable life support system must have the capability to rebuild and recycle them. We've only partially solved this problem on Earth, which is why industrial civilization is currently causing serious environmental damage. There are no inherent physical limitations to life in the solar system beyond Earth — both elemental building blocks and energy from the sun are abundant — but technological society, which developed as an outgrowth of the biosphere, cannot yet exist independently of it. The challenge of building and maintaining robust life-support systems for humans beyond Earth is a key reason why a machine-dominated approach to space exploration is so appealing...

However, it's notable that machines in space have not yet accomplished a basic task that biology performs continuously on Earth: acquiring raw materials and utilizing them for self-repair and growth. To many, this critical distinction is what separates living from non-living systems... The most advanced designs for self-assembling robots today begin with small subcomponents that must be manufactured separately beforehand. Overall, industrial technology remains Earth-centric in many important ways. Supply chains for electronic components are long and complex, and many raw materials are hard to source off-world... If we view the future expansion of life into space in a similar way as the emergence of complex life on land in the Paleozoic era, we can predict that new forms will emerge, shaped by their changed environment, while many historical characteristics will be preserved. For machine technology in the near term, evolution in a more life-like direction seems likely, with greater focus on regenerative parts and recycling, as well as increasingly sophisticated self-assembly capabilities. The inherent cost of transporting material out of Earth's gravity well will provide a particularly strong incentive for this to happen.

If building space habitats is hard and machine technology is gradually developing more life-like capabilities, does this mean we humans might as well remain Earth-bound forever? This feels hard to accept because exploration is an intrinsic part of the human spirit... To me, the eventual extension of the entire biosphere beyond Earth, rather than either just robots or humans surrounded by mechanical life-support systems, seems like the most interesting and inspiring future possibility. Initially, this could take the form of enclosed habitats capable of supporting closed-loop ecosystems, on the moon, Mars or water-rich asteroids, in the mold of Biosphere 2. Habitats would be manufactured industrially or grown organically from locally available materials. Over time, technological advances and adaptation, whether natural or guided, would allow the spread of life to an increasingly wide range of locations in the solar system.
The article ponders the benefits (and the history) of both approaches — with some fasincating insights along the way.

"If genuine alien life is out there somewhere, we'll have a much better chance of comprehending it once we have direct experience of sustaining life beyond our home planet."

UPDATE (1:16 PST) Today's launch has been scrubbed due to weather, and Blue Origin is now reviewing opportunities for new launch windows.

Sunday Morning Blue Origin livestreamed the planned launch of its New Glenn rocket, which will carry a very unique mission for NASA. "Twin spacecraft are set to take off on an unprecedented, winding journey to Mars," reports CNN, "where they will investigate why the barren red planet began to lose its atmosphere billions of years ago." By observing two Mars locations simultaneously, this mission can measure how Mars responds to space weather in real time — and how the Martian magnetosphere changes... Called EscaPADE, the mission will aim for an orbital trajectory that has never been attempted before, according to aerospace company Advanced Space, which is supporting the project. If successful, it could be a crucial case study that can allow extraordinary flexibility for planetary science missions down the road. The robotic mission plans to spend a year idling in an orbital backroad before heading to its target destination... [R]ather than turning toward Mars, the two orbiters will instead aim for Lagrange Point 2, or L2 — a cosmic balance point about 1.5 million kilometers (930,000 miles) from Earth. Lagrange points are special because they act as gravitational wells in which the pull of the sun and Earth are in perfect balance. The conditions can allow spacecraft to linger without being dragged away... The spacecraft will then loop endlessly in a kidney bean-shaped orbit around L2 until next year's Mars transfer window opens.
This "launch and loiter" project is part of NASA's SIMPLEx [Small, Innovative Missions for Planetary Exploration] program, which seeks high-value missions for less money, notes CNN. "EscaPADE's cost was less than $100 million, compared with the roughly $300 million to $600 million price tags of other NASA satellites orbiting Mars."

"Blue Origin is also attempting to land and recover New Glenn's first-stage booster," notes another CNN article.

An Icelandic programmer successfully ran Doom on the European Space Agency's OPS-SAT satellite, proving that the iconic 1993 shooter can now run not just everywhere on Earth -- but in orbit. ZDNet reports: Olafur Waage, a senior software developer from Iceland who now works in Norway, explained at Ubuntu Summit 25.10 how he, a self-described "professional keyboard typist" and maker of funny videos, ended up making what is perhaps the game's most outlandish port yet: Doom running on a real satellite in orbit, the European Space Agency (ESA) OPS-SAT satellite. OPS-SAT, a "flying laboratory" for testing novel onboard computing techniques, was equipped with an experimental computer approximately 10 times more powerful than the norm for spacecraft. Waag explained, "OPS-SAT was the first of its kind, devoted to demonstrating drastically improved mission control capabilities when satellites can fly more powerful onboard computers. The point was to break the curse of being too risk-averse with multi-million-dollar spacecraft." (The satellite was decommissioned in 2024.) [...]

Running Doom in orbit was partly a challenge of portability and partly a challenge of the limitations of space hardware and mission control. The on-board ARM dual-core Cortex-A9 processor, while hot stuff for space computing hardware (which tends to be low-powered and radiation-hardened), was slow even by Earth-bound standards. Waage chose Chocolate Doom 2.3, a popular open-source version of Doom, for its compatibility with the Ubuntu 18.04 Long Term Support (LTS) distro, which was already running on OPS-SAT. Besides, Waage noted, "We picked Chocolate Doom 2.3 because of the libraries available for 18.04 -- that was the last one that would actually build.

Updating software in orbit is extremely difficult, so relatively little code would have to be uploaded. As Waage said, "Doom is relatively straightforward C with a few external dependencies." In other words, it's easy to port. [...] The only sign that Doom was running in space at first was a lone log entry. So, the team used the satellite's camera to snap real-time images of the Earth, then swapped Doom's Mars skybox for actual satellite photos. "The idea was to take a screenshot from the satellite and use that as the sky, all rendered in software using the game's restricted 256-color palette," explained Waage. Even this posed unexpected difficulties: "Trying to draw all of these beautiful colors with those colors," said Waage, "it's probably not going to work right off. But we tried gradient tests, NASA demo photos. It took quite a bit of tweaking." Eventually, instead of a fantasy Mars as the sky background, they got a good-looking, real Earth in the game's sky. The game itself ran flawlessly. After all, Waage said, "It ran beautifully. It's on Ubuntu."

NASA has reopened SpaceX's $4.4 billion moon lander contract to new bidders like Blue Origin and Lockheed Martin after delays in Starship's development threatened the 2027 Artemis 3 mission. Reuters reports: The move paves the way for rivals such as Jeff Bezos' Blue Origin to snatch a high-profile mission to land the first astronauts on the moon in half a century. "I'm in the process of opening that contract up. I think we'll see companies like Blue get involved, and maybe others," the U.S. space agency's acting chief Sean Duffy, who also serves as U.S. Transportation Secretary, told Fox News' "Fox & Friends" program.

Duffy's comments follow months of mounting pressure within NASA to speed up its Artemis lunar program and push SpaceX to make greater progress on its Starship lunar lander, while China progresses toward its own goal of sending humans to the moon by 2030. It represents a major shift in NASA's lunar strategy, starting a new competitive juncture in the program for a crewed moon lander just two years before the scheduled landing date. Blue Origin is widely expected to compete for the mission, while Lockheed Martin has indicated it would convene an industry team to heed NASA's call.

Starship, picked by NASA in 2021 under a contract now worth $4.4 billion, faces a 2027 moon landing deadline that agency advisers estimate could slip years behind schedule, citing competing priorities. Musk sees Starship as crucial to launching larger batches of Starlink satellites to space and eventually ferrying humans to Mars, among other missions. "They do remarkable things, but they're behind schedule," Duffy said of SpaceX's lunar lander work, adding President Donald Trump wants to see the mission take place before his White House term ends in January 2029.

A new study shows that common baker's yeast (Saccharomyces cerevisiae) can survive Mars-like conditions, including meteorite shock waves and toxic perchlorate salts found in Martian soil. Phys.org reports: Published in PNAS Nexus, Purusharth I. Rajyaguru and colleagues subjected Saccharomyces cerevisiae, which is a widely used model yeast, to shock waves and perchlorates. The authors chose the yeast in part because it has already been studied in space. When stressed, yeast, humans, and many other organisms form ribonucleoprotein (RNP) condensates, structures made of RNA and proteins that protect RNA and affect the fates of mRNAs. When the stressor passes, the RNP condensates, which include subtypes known as stress granules and P-bodies, disassemble.

The authors simulated Martian shock waves at the High-Intensity Shock Tube for Astrochemistry (HISTA) housed in the Physical Research Laboratory in Ahmedabad, India. Yeast exposed to 5.6 Mach intensity shock waves survived with slowed growth, as did yeast subjected to 100 mM sodium salt of perchlorate (NaClO4) -- a concentration similar to that in Martian soils. Yeast cells also survived exposure to the combined stress of shock waves and perchlorate stress. In both cases, the yeast assembled RNP condensates. Shock waves induced the assembly of stress granules and P-bodies; perchlorate caused yeast to make P-bodies but not stress granules. Mutants incapable of assembling RNP condensates were poor at surviving the Martian stress condition. Transcriptome analysis identified specific RNA transcripts perturbed by Mars-like conditions.

The heliosphere "plays a major role in why life is possible on our planet," reports CNN, "and how it perhaps once existed on others such as Mars." (Basically solar winds create "a constant flow of charged particles" that form "an enormous bubble that protects the planets in our solar system from cosmic radiation permeating the Milky Way".)

NASA says the heliosphere's boundary is three times the distance between Earth and Pluto. (After leaving the heliosphere NASA's Voyager probes collected key data about the heliosphere.) But now there's a new mission to investigate "how that solar wind interacts with interstellar space at the boundary of the heliosphere," CNN reports — called the Interstellar Mapping and Acceleration Probe (or IMAP): The spacecraft's 10 instruments will also fill gaps in the existing map of the heliosphere, pieced together from data collected by previous missions, and help further explain how the heliosphere largely shields our solar system from damaging cosmic rays, the most highly energetic particles in the universe. Along with two other space weather missions that lifted off aboard the same rocket on Wednesday, IMAP will help scientists better predict when solar storms unleashed by the sun could affect our planet. When aimed at Earth, harsh radiation from the storms, also known as space weather, can pose risks to astronauts on the International Space Station as well as interfere with communications, the electric power grid, navigation, and radio and satellite operations.

"This next set of missions is the ultimate cosmic carpool," said Dr. Joe Westlake, director of NASA's Heliophysics Division, during a news conference on Sunday. "They will provide unprecedented insight into space weather. Every human on Earth, as well as nearly every system involved in space exploration and human needs, is affected by space weather...." The IBEX, or Interstellar Boundary Explorer, satellite has been mapping the heliosphere since launching in 2008. But IMAP can explore and map the boundaries of the heliosphere like never before because it has instruments with faster imaging that are capable of 30 times higher resolution. Once it reaches an orbit about 1 million miles (1.6 million kilometers) from Earth in about three months, IMAP will also capture observations of the solar wind in real time and measure particles that travel from the sun, study the heliosphere's boundary between 6 billion and 9 billion miles (9.7 billion to 14.5 billion kilometers) away, and even collect data from interstellar space.
Also launching was the SWFO-L1 mission, which CNN says is "intended to act as a solar storm detector, providing early warnings to protect astronauts in low-Earth orbit and satellites that provide critical communications on Earth. It's a tool that will be even more necessary as astronauts venture farther into deep space."

NASA streamed the launch live on YouTube.

NASA has unveiled 10 new astronaut candidates drawn from over 8,000 applicants. The diverse group includes four men and six women -- pilots, scientists, and medical professionals -- who will train for future missions to the ISS, the moon, and eventually Mars. CBS News reports: This is NASA's first astronaut class with more women than men. It includes six pilots with experience in high-performance aircraft, a biomedical engineer, an anesthesiologist, a geologist and a former SpaceX launch director. Among the new astronaut candidates is 39-year-old Anna Menon, a mother of two who flew to orbit in 2024 aboard a SpaceX Crew Dragon as a private astronaut on a commercial, non-NASA flight. [...]

The other members of the 2025 astronaut class are:
- Army Chief Warrant Officer 3 Ben Bailey, 38, a graduate of the Naval Test Pilot School with more than 2,000 hours flying more than 30 different aircraft, including recent work with UH-60 Black Hawk and CH-47F Chinook helicopters.
- Lauren Edgar, 40, who holds a Ph.D. in geology from the California Institute of Technology, with experience supporting NASA's Mars exploration rovers and, more recently, serving as a deputy principal investigator with NASA's Artemis 3 moon landing mission.
- Air Force Maj. Adam Fuhrmann, 35, an Air Force Test Pilot School graduate with more than 2,100 hours flying F-16 and F-35 jets. He holds a master's degree in flight test engineering.
- Air Force Maj. Cameron Jones, 35, another graduate of Air Force Test Pilot School as well as the Air Force Weapons School with more than 1,600 hours flying high-performance aircraft, spending most of his time flying the F-22 Raptor.
- Yuri Kubo, 40, a former SpaceX launch director with a master's in electrical and computer engineering who also competed in ultimate frisbee contests.
- Rebecca Lawler, 38, a former Navy P-3 Orion pilot and experimental test pilot with more than 2,800 hours of flight time, including stints flying a NOAA hurricane hunter aircraft. She was a Naval Academy graduate and was a test pilot for United Airlines at the time of her selection.
- Imelda Muller, 34, a former undersea medical officer for the Navy with a medical degree from the University of Vermont's Robert Larner College of Medicine; she was completing her residency in anesthesia at Johns Hopkins University School of Medicine in Baltimore at the time of her astronaut selection.
- Navy Lt. Cmdr. Erin Overcash, 34, a Naval Test Pilot School graduate and an experienced F/A-18 and F/A-18F Super Hornet pilot with 249 aircraft carrier landings. She also trained with the USA Rugby Women's National Team.
- Katherine Spies, 43, a former Marine Corps AH-1 attack helicopter pilot and a graduate of the Naval Test Pilot School with more than 2,000 hours flying time. She was director of flight test engineering for Gulfstream Aerospace Corp. at the time of her astronaut selection.

"Engineers from Ohio State University are developing a new way to power rocket engines," reports Gizmodo, "using liquid uranium for a faster, more efficient form of nuclear propulsion that could deliver round trips to Mars within a single year..." Nuclear propulsion uses a nuclear reactor to heat a liquid propellant to extremely high temperatures, turning it into a gas that's expelled through a nozzle and used to generate thrust. The newly developed engine concept, called the centrifugal nuclear thermal rocket (CNTR), uses liquid uranium to heat rocket propellant directly. In doing so, the engine promises more efficiency than traditional chemical rockets, as well as other nuclear propulsion engines, according to new research published in Acta Astronautica...

Traditional chemical engines produce about 450 seconds of thrust from a given amount of propellant, a measure known as specific impulse. Nuclear propulsion engines can reach around 900 seconds, with the CNTR possibly pushing that number even higher. "You could have a safe one-way trip to Mars in six months, for example, as opposed to doing the same mission in a year," Spencer Christian, a PhD student at Ohio State and leader of CNTR's prototype construction, said in a statement.

CNTR promises faster routes, but it could also use different types of propellant, like ammonia, methane, hydrazine, or propane, that can be found in asteroids or other objects in space.
"Some potential hurdles include ensuring that the methods used for startup, operation and shutdown avoid instabilities," according to the researchers' announcement, as well as "envisioning ways to minimize the loss of uranium fuel and accommodate potential engine failures."

But "This team's CNTR concept is expected to reach design readiness within the next five years..."

One of the worlds in the TRAPPIST-1 system, a mere 40 light-years away, just might be clad in a life-supporting atmosphere," reports ScienceAlert.

"In exciting new JWST observations, the Earth-sized exoplanet TRAPPIST-1e shows hints of a gaseous envelope similar to our own, one that could facilitate liquid water on the surface." Although the detection is ambiguous and needs extensive follow-up to find out what the deal is, it's the closest astronomers have come yet in their quest to find a second Earth... [T]he first step is finding exoplanets that are the right distance from their host star, occupying a zone where water neither freezes under extreme cold nor evaporates under extreme heat. Announced in 2016, the discovery of the TRAPPIST-1 system was immediately exciting for this reason. The red dwarf star hosts seven exoplanets that have a rocky composition (as opposed to gas or ice giants), several of which are bang in the star's habitable, liquid water zone...

Red dwarf stars are also much more active than Sun-like stars, rampant with flare activity that, scientists have speculated, may have stripped any planetary atmospheres in the vicinity. Closer inspections of TRAPPIST-1d, one of the other worlds in the star's habitable zone, have turned up no trace of an atmosphere. But TRAPPIST-1e is a little more comfortably located, at a slightly greater distance from the star... [T]he spectrum is consistent with an atmosphere rich in molecular nitrogen, with trace amounts of carbon dioxide and methane.

This is pretty tantalizing. Earth's atmosphere is roughly 78 percent molecular nitrogen. If the results can be validated, TRAPPIST-1e might just be the most Earth-like exoplanet discovered to date. That is not a small if, though. Luckily, more JWST observations are in the pipeline, and the researchers should be able to validate or rule out an atmosphere very soon.
After analyzing four transits of TRAPPIST-1e across TRAPPIST-1, "We are seeing two possible explanations," says astrophysicist Ryan MacDonald of the University of St Andrews in the UK. "The most exciting possibility is that TRAPPIST-1e could have a so-called secondary atmosphere containing heavy gases like nitrogen. "But our initial observations cannot yet rule out a bare rock with no atmosphere..."

Astrophysicist Ana Glidden of MIT led the second team interpreting the results, and says "We are really still in the early stages of learning what kind of amazing science we can do with Webb. It's incredible to measure the details of starlight around Earth-sized planets 40 light-years away and learn what it might be like there, if life could be possible there."

"We're in a new age of exploration that's very exciting to be a part of."

NASA: After a year's worth of scientific scrutiny, the 'Sapphire Canyon' rock sample remains the mission's best candidate for containing signs of ancient microbial life processes. A sample collected by NASA's Perseverance Mars rover from an ancient dry riverbed in Jezero Crater could preserve evidence of ancient microbial life. Taken from a rock named "Cheyava Falls" last year, the sample, called "Sapphire Canyon," contains potential biosignatures, according to a paper published Wednesday in the journal Nature.

A potential biosignature is a substance or structure that might have a biological origin but requires more data or further study before a conclusion can be reached about the absence or presence of life. "This finding by Perseverance, launched under President Trump in his first term, is the closest we have ever come to discovering life on Mars. The identification of a potential biosignature on the Red Planet is a groundbreaking discovery, and one that will advance our understanding of Mars," said acting NASA Administrator Sean Duffy. "NASA's commitment to conducting Gold Standard Science will continue as we pursue our goal of putting American boots on Mars' rocky soil."

Somewhere in Houston, four research volunteers "will soon participate in NASA's year-long simulation of a Mars mission," NASA announced this week, saying it will provide "foundational data to inform human exploration of the Moon, Mars, and beyond."

The 378-day simulation will take place inside a 3D-printed, 1,700-square-foot habitat at NASA's Johnson Space Center in Houston — starting on October 19th and continuing until Halloween of 2026: Through a series of Earth-based missions called CHAPEA (Crew Health and Performance Exploration Analog), NASA aims to evaluate certain human health and performance factors ahead of future Mars missions. The crew will undergo realistic resource limitations, equipment failures, communication delays, isolation and confinement, and other stressors, along with simulated high-tempo extravehicular activities. These scenarios allow NASA to make informed trades between risks and interventions for long-duration exploration missions.

"As NASA gears up for crewed Artemis missions, CHAPEA and other ground analogs are helping to determine which capabilities could best support future crews in overcoming the human health and performance challenges of living and operating beyond Earth's resources — all before we send humans to Mars," said Sara Whiting, project scientist with NASA's Human Research Program at NASA Johnson. Crew members will carry out scientific research and operational tasks, including simulated Mars walks, growing a vegetable garden, robotic operations, and more. Technologies specifically designed for Mars and deep space exploration will also be tested, including a potable water dispenser and diagnostic medical equipment...

This mission, facilitated by NASA's Human Research Program, is the second one-year Mars surface simulation conducted through CHAPEA. The first mission concluded on July 6, 2024.

An anonymous reader quotes a report from TechCrunch: SpaceX has long marketed Starship as a fully and rapidly reusable rocket that's designed to deliver thousands of pounds of cargo to Mars and make life multiplanetary. But reusability at scale means a space vehicle that can tolerate mishaps and faults, so that a single failure doesn't spell a mission-ending catastrophe. The 10th test flight on Tuesday evening demonstrated SpaceX's focus on fault tolerance. In a post-flight update, SpaceX said the test stressed "the limits of vehicle capabilities." Understanding these edges will be critical for the company's plans to eventually use Starship to launch Starlink satellites, commercial payloads, and eventually astronauts.

When the massive Starship rocket lifted off on its 10th test flight Tuesday evening, SpaceX did more than achieve new milestones. It purposefully introduced several faults to test the heat shield, propulsion redundancy, and the relighting of its Raptor engine. The heat shield is among the toughest engineering challenges facing SpaceX. As Elon Musk acknowledged on X in May 2024, a reusable orbital return heat shield is the "biggest remaining problem" to 100% rocket reusability. The belly of the upper stage, also called Starship, is covered in thousands of hexagonal ceramic and metallic tiles, which make up the heat shield. Flight 10 was all about learning how much damage the ship can accept and survive when it goes through atmospheric heating. During the tenth test, engineers intentionally removed tiles from some sections of the ship, and experimented with a new type of actively cooled tile, to gather real-world data and refine designs. [...]

Propulsion redundancy was also put to the test. The Super Heavy booster's landing burn configuration appeared to be a rehearsal for engine failure. Engineers intentionally disabled one of the three center Raptor engines during the final phase of the burn and used a backup engine in its place. That was a successful rehearsal for an engine-out event. Finally, SpaceX reported the in-space relight of a Raptor engine, described on the launch broadcast as the second time SpaceX has pulled this off. Reliable engine restarts will be necessary for deep-space missions, propellant transfers, and possibly some payload deployment missions. [...] The next step is translating Flight 10 data into future hardware upgrades to move closer to routine operations and days when, as Musk envisioned, "Starship launches more than 24 times in 24 hours."

The mysterious X-37B space-plane — the U.S. military's orbital test vehicle — "serves partly as a platform for cutting-edge experiments," writes Space.com

And "one of these experiments is a potential alternative to GPS that makes use of quantum science as a tool for navigation: a quantum inertial sensor." This technology could revolutionize how spacecraft, airplanes, ships and submarines navigate in environments where GPS is unavailable or compromised. In space, especially beyond Earth's orbit, GPS signals become unreliable or simply vanish. The same applies underwater, where submarines cannot access GPS at all. And even on Earth, GPS signals can be jammed (blocked), spoofed (making a GPS receiver think it is in a different location) or disabled — for instance, during a conflict... Traditional inertial navigation systems, which use accelerometers and gyroscopes to measure a vehicle's acceleration and rotation, do provide independent navigation, as they can estimate position by tracking how the vehicle moves over time... Eventually though, without visual cues, small errors will accumulate and you will entirely lose your positioning...

At very low temperatures, atoms obey the rules of quantum mechanics: they behave like waves and can exist in multiple states simultaneously — two properties that lie at the heart of quantum inertial sensors. The quantum inertial sensor aboard the X-37B uses a technique called atom interferometry, where atoms are cooled to the temperature of near absolute zero, so they behave like waves. Using fine-tuned lasers, each atom is split into what's called a superposition state, similar to Schrödinger's cat, so that it simultaneously travels along two paths, which are then recombined.

Since the atom behaves like a wave in quantum mechanics, these two paths interfere with each other, creating a pattern similar to overlapping ripples on water. Encoded in this pattern is detailed information about how the atom's environment has affected its journey. In particular, the tiniest shifts in motion, like sensor rotations or accelerations, leave detectable marks on these atomic "waves". Compared to classical inertial navigation systems, quantum sensors offer orders of magnitude greater sensitivity. Because atoms are identical and do not change, unlike mechanical components or electronics, they are far less prone to drift or bias. The result is long duration and high accuracy navigation without the need for external references.

The upcoming X-37B mission will be the first time this level of quantum inertial navigation is tested in space.
The article points out that a quantum navigation system could be crucial "for future space exploration, such as to the Moon, Mars or even deep space," where autonomy is key and when signals from Earth are unavailable.

"While quantum computing and quantum communication often steal headlines, systems like quantum clocks and quantum sensors are likely to be the first to see widespread use."

After five months on the International Space Station, four astronauts splashed down in the Pacific Ocean in a SpaceX Crew Dragon capsule named Endurance, reports Space.com.

It was NASA's 10th commercial crew rotation mission: The flight launched atop a SpaceX Falcon 9 rocket on March 14 and arrived at the orbiting lab two days later. Crew-10's four astronauts soon set to conducting science work, which consumed much of their time over the ensuing months... The wheels for Crew-10's departure began turning last Saturday (Aug. 2), when SpaceX's four-person Crew-11 mission arrived at the International Space Station. The Crew-10 astronauts spent a few days advising their replacements, then set their minds to gearing up for the return to Earth — and reflecting on their orbital experience.

"We got to accomplish a lot of really amazing operational things," Ayers said during a farewell ceremony on Tuesday (Aug. 5). "We got to see some amazing views, and we have had some really big belly laughs and a wonderful time together," she added. "I think that [we're] leaving with a heart full of gratitude, and [we're] excited to see where the International Space Station goes after we get home." The hatches between Endurance and the ISS closed on Friday (Aug. 8) at 4:20 p.m. EDT (2020 GMT), and the capsule undocked about two hours later, at 6:15 p.m. EDT (2205 GMT). Endurance then began maneuvering its way back to Earth, setting up its splashdown today.

It was the first Pacific Ocean return for a SpaceX CCP mission; all previous such flights have come down off the Florida coast. SpaceX recently shifted to West Coast reentries for all of its Dragon missions, both crewed and uncrewed, to minimize the chance that falling space debris could damage property or injure people.
"During their mission, crew members traveled nearly 62,795,205 million miles," NASA announced, "and completed 2,368 orbits around Earth..." Along the way, Crew-10 contributed hundreds of hours to scientific research, maintenance activities, and technology demonstrations. McClain, Ayers, and Onishi completed investigations on plant and microalgae growth, examined how space radiation affects DNA sequences in plants, observed how microgravity changes human eye structure and cells in the body, and more. The research conducted aboard the orbiting laboratory advances scientific knowledge and demonstrates new technologies that enable us to prepare for human exploration of the Moon and Mars.

McClain and Ayers also completed a spacewalk on May 1, relocating a communications antenna, beginning the installation of a mounting bracket for a future International Space Station Roll-Out Solar Array, and other tasks.

At Sotheby's Geek Week auction, the largest known Martian meteorite on Earth sold for a record-breaking $5.3 million. The Associated Press reports: The 54-pound (25-kilogram) rock named NWA 16788 was discovered in the Sahara Desert in Niger by a meteorite hunter in November 2023, after having been blown off the surface of Mars by a massive asteroid strike and traveling 140 million miles (225 million kilometers) to Earth, according to Sotheby's. The estimated sale price before the auction was $2 million to $4 million. The identity of the buyer was not immediately disclosed. The final bid was $4.3 million. Adding various fees and costs, the official sale price was about $5.3 million, making it the most valuable meteorite ever sold at auction, Sotheby's said.

The live bidding was slow, with the auctioneer trying to coax more offers and decreasing the minimum bid increases. [...] The bidding for the Mars meteorite began with two advance offers of $1.9 million and $2 million. The live bidding slowly proceeded with increases of $200,000 and $300,000 until $4 million, then continued with $100,000 increases until reaching $4.3 million. The red, brown and gray meteorite is about 70% larger than the next largest piece of Mars found on Earth and represents nearly 7% of all the Martian material currently on this planet, Sotheby's says. It measures nearly 15 inches by 11 inches by 6 inches (375 millimeters by 279 millimeters by 152 millimeters). It was also a rare find. There are only 400 Martian meteorites out of the more than 77,000 officially recognized meteorites found on Earth, the auction house says.

Astronomers have detected a mysterious "interstellar object," dubbed A11pl3Z, speeding through the solar system at 152,000 mph. If confirmed, it would be just the third known interstellar visitor, following 'Oumuamua and Comet Borisov. The visiting space object will pass near Mars and the Sun later this year before leaving the solar system forever. Live Science reports: The newly discovered object, currently dubbed A11pl3Z, was first spotted in data collected between June 25 and June 29 by the Asteroid Terrestrial-impact Last Alert System (ATLAS), which automatically scans the night sky using telescopes in Hawaii and South Africa. The mystery object was confirmed by both NASA's Center for Near Earth Object Studies and the International Astronomical Union's Minor Planet Center on Tuesday (July 1), according to EarthSky.org.

A11pl3Z is most likely a large asteroid, or maybe a comet, potentially spanning up to 12 miles (20 kilometers). It is traveling toward the inner solar system at around 152,000 mph (245,000 km/h) and is approaching us from the part of the night sky where the bar of the Milky Way is located. Based on A11pl3Z's speed and trajectory, experts think it originated from beyond the sun's gravitational influence and has enough momentum to shoot straight through our cosmic neighborhood without slowing down. However, more observations are needed to tell for sure.

"Earth's ozone layer blocks the Sun's shortest wave radiation, called UV-C, which is so damaging to cells in high doses that it's a go-to sterilizer in hospitals," writes Slashdot reader sciencehabit. "UV-C is such a killer, in fact, that scientists have questioned whether life can survive on worlds that lack an ozone layer, such as Mars or distant exoplanets.

"But research published this month in Astrobiology suggests one hardy lichen, a hybrid organism made of algae and fungi, may have cracked the UV-C code with a built-in sunscreen, despite never experiencing these rays in its long evolutionary history."

Science magazine explains: When scientists brought a sample of the species, the common desert dweller Clavascidium lacinulatum, back to the lab, graduate student Tejinder Singh put the lichen through the wringer. First, Singh dehydrated the lichen, to make sure it couldn't grow back in real time and mask any UV damage. Then he placed the lichen a few centimeters under a UV lamp and blasted it with radiation. The lichen seemed just fine.

So Singh purchased the most powerful UV-C lamp he could find online, capable of sending out 20 times more radiation than the amount expected on Mars. When he tested the lamp on the most radiation-resistant life form on Earth, the bacterium Deinococcus radiodurans, it died in less than a minute. After 3 months—likely the highest amount of UV-C radiation ever tested on an organism—Singh pulled the sample so he could finish his master's thesis in time. About half of the lichen's algal cells had survived. Then, when the team ground up and cultured part of the surviving lichen, about half of its algal cells sprouted new, green colonies after 2 weeks, showing it maintained the ability to reproduce.

The species may provide a blueprint for surviving on Mars or exoplanets, which don't have an ozone layer to protect them.

alternative_right shares a report from Phys.Org: Using conventional propulsion and low-energy trajectories, it takes six to nine months for crewed spacecraft to reach Mars. These durations complicate mission design and technology requirements and raise health and safety concerns since crews will be exposed to extended periods in microgravity and heightened exposure to cosmic radiation. Traditionally, mission designers have recommended nuclear-electric or nuclear-thermal propulsion (NEP/NTP), which could shorten trips to just 3 months. In a recent study, a UCSB physics researcher identified two trajectories that could reduce transits to Mars using the Starship to between 90 and 104 days.

The study was authored by Jack Kingdon, a graduate student researcher in the Physics Department at the University of California, Santa Barbara (UCSB). He is also a member of the UCSB Weld Lab, an experimental ultracold atomic physics group that uses quantum degenerate gases to explore quantum mechanical phenomena. [...] As outlined on its website, conference presentations, and user manual, the SpaceX mission architecture consists of six Starships traveling to Mars. Four of these spacecraft will haul 400 metric tons (440 U.S. tons) of cargo while two will transport 200 passengers. Based on the Block 2 design, which has a 1,500 metric ton (1,650 U.S. ton) propellant capacity, the crewed Starships will require 15 tankers to fully refuel in low Earth orbit (LEO). The cargo ships would require only four, since they would be sent on longer low-energy trajectories. Once the flotilla arrives at Mars, the Starships will refuel using propellant created in situ using local carbon dioxide and water ice. When the return window approaches, one of the crew ships and 3-4 cargo ships will refuel and then launch into a low Mars orbit (LMO). The cargo ships will then transfer the majority of their propellant to the crew ship and return to the surface of Mars. The crew ship would then depart for Earth, and the process could be repeated for the other crew ship.

Kingdon calculated multiple trajectories using a Lambert Solver, which produces the shortest elliptical arc in two-body problem equations (aka Lambert's problem). The first would depart Earth on April 30th, 2033, taking advantage of the 26-month periodic alignment between Earth and Mars. The transit would last 90 days, with the crew returning to Earth after another 90-day transit by July 2nd, 2035. The second would depart Earth on July 15th, 2035, and return to Earth after a 104-day transit on December 5th, 2037. As Kingdon explained, the former trajectory is the most likely to succeed: "The optimal trajectory is the 2033 trajectory -- it has the lowest fuel requirements for the fastest transit time. A note that may not be obvious to the layreader is that Starship can very easily reach Mars in ~3 months -- in fact, it can in any launch window, over a fairly wide range of trajectories. However, Starship may impact the Martian atmosphere too fast (although we do not know, and likely SpaceX don't either actually how fast Starship can hit the Martian atmosphere and survive). The trajectories discussed are ones that I am confident Starship will survive." The paper describing the work has been published in the journal Scientific Reports.

President Trump's 2026 budget proposes over $1 billion for Mars exploration through a new Commercial Mars Payload Services Program, while simultaneously slashing NASA's overall budget by 25%. Phys.Org reports: Under the proposal, NASA would award contracts to companies developing spacesuits, communications systems and a human-rated landing vehicle to foster exploration of the Red Planet. Trump's proposed $18.8 billion NASA budget would cut the agency's funding by about 25% from the year before, with big hits to its science portfolio. The fleshed-out request on Friday builds upon a condensed budget proposal released earlier this month.

"We must continue to be responsible stewards of taxpayer dollars," NASA Acting Administrator Janet Petro wrote in a letter included in the request. "That means making strategic decisions -- including scaling back or discontinuing ineffective efforts." The new Mars scheme is modeled after NASA's Commercial Lunar Payload Services program that has benefited Intuitive Machines LLC, Firefly Aerospace Inc. and Astrobotic Technology Inc., though it has achieved mixed results. According to the budget, the contract to land on Mars would build upon existing lander contracts. America's Next NASA Administrator Will Not Be Former SpaceX Astronaut Jared Isaacman

In December it looked like NASA's next administrator would be the billionaire businessman/space enthusiast who twice flew to orbit with SpaceX.

But Saturday the nomination was withdrawn "after a thorough review of prior associations," according to an announcement made on social media. The Guardian reports: His removal from consideration caught many in the space industry by surprise. Trump and the White House did not explain what led to the decision... In [Isaacman's] confirmation hearing in April, he sought to balance Nasa's existing moon-aligned space exploration strategy with pressure to shift the agency's focus on Mars, saying the US can plan for travel to both destinations. As a potential leader of Nasa's 18,000 employees, Isaacman faced a daunting task of implementing that decision to prioritize Mars, given that Nasa has spent years and billions of dollars trying to return its astronauts to the moon...

Some scientists saw the nominee change as further destabilizing to Nasa as it faces dramatic budget cuts without a confirmed leader in place to navigate political turbulence between Congress, the White House and the space agency's workforce.
"It was unclear whom the administration might tap to replace Isaacman," the article adds, though "One name being floated is the retired US air force Lt Gen Steven Kwast, an early advocate for the creation of the US Space Force..."

Ars Technica notes that Kwast, a former Lieutenant General in the U.S. Air Force, has a background that "seems to be far less oriented toward NASA's civil space mission and far more focused on seeing space as a battlefield — decidedly not an arena for cooperation and peaceful exploration."