NASA's independent study to delve into the mysteries surrounding unidentified aerial phenomena kicked off today. CNN reports: The group will include experts across numerous disciplines -- including astrobiology, data science, oceanography, genetics, policy and planetary science -- as well as retired NASA astronaut Scott Kelly, a former fighter pilot and test pilot and retired US Navy captain. The space agency, which first announced it was forming the group in June, previously revealed that the team would be led by astrophysicist David Spergel, who is president of the Simons Foundation in New York City.

The new group won't necessarily seek to determine exactly what the UAPs, which have been seen moving through restricted military airspace over the past several decades, are. Rather, the team will look to hash out exactly how it's best for NASA to approach further study of the phenomenon. The space agency has already noted that the limited number of observations of UAPs has made it difficult to draw scientific conclusions about the nature of such events. "Without access to an extensive set of data, it is nearly impossible to verify or explain any observation, thus the focus of the study is to inform NASA what possible data could be collected in the future to scientifically discern the nature of UAP," according to a NASA news release.

This study, expected to last about nine months, will also be entirely unclassified and within the public domain. "Exploring the unknown in space and the atmosphere is at the heart of who we are at NASA," Zurbuchen said in a Friday statement. "Understanding the data we have surrounding unidentified aerial phenomena is critical to helping us draw scientific conclusions about what is happening in our skies. Data is the language of scientists and makes the unexplainable, explainable." Specifically, the team will look for data on "events in the sky that cannot be identified as aircraft or known natural phenomena -- from a scientific perspective," the agency said. Unidentified aerial phenomena are of interest, NASA said, from a security and safety perspective. There was no evidence UAPs are extraterrestrial in origin, NASA emphasized during the initial announcement in June.

NASA's James Webb Space Telescope has captured a lush, highly detailed landscape -- the iconic Pillars of Creation -- where new stars are forming within dense clouds of gas and dust. From NASA: The three-dimensional pillars look like majestic rock formations, but are far more permeable. These columns are made up of cool interstellar gas and dust that appear -- at times -- semi-transparent in near-infrared light. Webb's new view of the Pillars of Creation, which were first made famous when imaged by NASA's Hubble Space Telescope in 1995, will help researchers revamp their models of star formation by identifying far more precise counts of newly formed stars, along with the quantities of gas and dust in the region. Over time, they will begin to build a clearer understanding of how stars form and burst out of these dusty clouds over millions of years.

Newly formed stars are the scene-stealers in this image from Webb's Near-Infrared Camera (NIRCam). These are the bright red orbs that typically have diffraction spikes and lie outside one of the dusty pillars. When knots with sufficient mass form within the pillars of gas and dust, they begin to collapse under their own gravity, slowly heat up, and eventually form new stars. What about those wavy lines that look like lava at the edges of some pillars? These are ejections from stars that are still forming within the gas and dust. Young stars periodically shoot out supersonic jets that collide with clouds of material, like these thick pillars. This sometimes also results in bow shocks, which can form wavy patterns like a boat does as it moves through water. The crimson glow comes from the energetic hydrogen molecules that result from jets and shocks. This is evident in the second and third pillars from the top -- the NIRCam image is practically pulsing with their activity. These young stars are estimated to be only a few hundred thousand years old.

Although it may appear that near-infrared light has allowed Webb to "pierce through" the clouds to reveal great cosmic distances beyond the pillars, there are no galaxies in this view. Instead, a mix of translucent gas and dust known as the interstellar medium in the densest part of our Milky Way galaxy's disk blocks our view of the deeper universe. This scene was first imaged by Hubble in 1995 and revisited in 2014, but many other observatories have also stared deeply at this region. Each advanced instrument offers researchers new details about this region, which is practically overflowing with stars. This tightly cropped image is set within the vast Eagle Nebula, which lies 6,500 light-years away.

After 170 days in space, four astronauts splashed down in the Atlantic Ocean on Friday, bringing an end to a successful NASA-SpaceX mission to the International Space Station. From a report: Following two days of weather delays, SpaceX's Crew Dragon Freedom returned to Earth off the coast of Jacksonville, Florida, beneath clear blue skies and into mild seas. The spacecraft's descent through Earth's atmosphere appeared to be nominal, with two drogue parachutes deploying on schedule, followed by four clean main parachutes, allowing Dragon to splash down at about 25 km per hour. "SpaceX, from Freedom, thank you for an incredible ride up to orbit and an incredible ride home," Kjell Lindgren, the NASA commander of the spacecraft, said after landing.

Lindgren led a mission that included NASA astronauts Bob Hines and Jessica Watkins, as well as European Space Agency astronaut Samantha Cristoforetti. Upon landing, the spacecraft was met by two SpaceX "fast boats" that secured the toasty-looking vehicle before it was brought on board the Megan recovery ship, named after Megan McArthur, an astronaut aboard an earlier SpaceX flight. This mission, Crew-4, was the fourth operational mission flown by SpaceX for NASA. Earlier this month, the Crew-5 mission launched four astronauts to the space station, where they will remain for about six months. Including an initial demonstration mission in 2020, and two private spaceflights -- Inspiration4 and Axiom-1 -- Crew Dragon has now carried 30 people into orbit.

In a little more than two years, SpaceX has surpassed the total number of astronauts launched into orbit by China, whose human spaceflight program dates back to 2003; and in the time Crew Dragon has been operational, it has exceeded even the Russian Soyuz vehicle in terms of the total number of people flown into space during that period. Over the last two years Dragon had a few flaws, including an intermittently problematic toilet and a lagging parachute on one flight, but NASA officials have been extremely pleased with the vehicle's performance. It has safely returned the United States' capability of human spaceflight, which had been lost since the space shuttle's retirement. Had Dragon not been available, NASA would have been in the uncomfortable position of relying on Russia for crew transport amid the Ukraine war.

SpaceX returned its fourth operational crew mission from the International Space Station on Friday, with the quartet of astronauts splashing down in the company's capsule off the coast of Florida. CNBC reports: The company's Crew Dragon spacecraft "Freedom" undocked from the ISS at around noon ET to begin the trip back to Earth, with splashdown happening around 5 p.m. ET. "Welcome home -- thanks for flying SpaceX," the company's mission control told the crew shortly after landing. "Thank you for an incredible ride to orbit, and an incredible ride home," Crew-4 commander Kjell Lindgren said in response.

Crew-4 includes NASA astronauts Lindgren, Bob Hines, and Jessica Watkins, as well as European Space Agency astronaut Samantha Cristoforetti. The mission launched in April for a six-month stay on the orbiting research laboratory. Elon Musk's company launched the Crew-5 mission last week, bringing four other astronauts to the ISS. SpaceX has now flown 30 people to orbit since its first crewed launch in May 2020, with six government missions and two private ones.

Entrepreneur Dennis Tito and his wife, Akiko Tito, announced Wednesday that they purchased two tickets on the second of SpaceX's planned circumlunar flights later this decade. Dennis Tito made history when he became the first person to pay for his own ride into space more than two decades ago. He flew aboard a Soyuz vehicle and spent a week on the International Space Station. As for his wife, Akiko Tito, she becomes the first woman confirmed to fly on Starship, notes Ars Technica. From the report: The flight will last about a week, outbound to the Moon, passing within about 40 km of the surface and flying back. Ten other seats on Starship remain unsold and are available. Tito said he was not at liberty to disclose the price he paid. This brings the manifest of private human spaceflights on Starship, and its Super Heavy rocket, to three. There is billionaire Jared Isaacman's Polaris III mission, likely to low Earth orbit, which will be followed by Japanese billionaire Yusaku Maezawa's "dearMoon" flight, the first human Starship flight around the Moon. Then comes Tito and the second circumlunar mission.

SpaceX has also contracted with NASA to fly the first human landing on the Moon as part of the Artemis program, but for now, NASA astronauts will launch on a separate rocket and rendezvous with Starship in lunar orbit to go down to the lunar surface and back to orbit. So far, NASA hasn't announced plans to launch astronauts from Earth on Starship or land them back here. The timeline for all of these missions hinges on the development of the Starship vehicle, which may make a debut orbital test flight in the coming months from South Texas. After that, the large, fully reusable launch system will fly dozens of uncrewed missions, mostly carrying Starlink payloads, before humans climb on board. This is because Starship will make a propulsive landing back on Earth -- something no crew vehicle has ever done -- and has no backup should there be some sort of landing failure.

An anonymous reader quotes a report from the Guardian: A spacecraft that plowed into a small, harmless asteroid millions of miles from Earth succeeded in shifting the orbit of the space rock, Nasa said on Tuesday, announcing the results of its first such test. The US space agency strategically launched the Double Asteroid Redirection Test ("Dart") spacecraft into the path of the asteroid, thereby throwing it off course. Nasa hopes to be able to deflect any asteroid or comet that comes to pose a real threat to Earth.

Dart altered the orbit of the Dimorphos asteroid by 32 minutes. Glaze said the minimum requirement for changing the orbital period was "really only 73 seconds." Last year, in a test that cost $325 million, another Dart spacecraft, roughly the size of a vending machine, was destroyed when it slammed into an asteroid 7m miles away, at 14,000mph.In a tweet, the vice-president, Kamala Harris, said: "Congratulations to the team at Nasa for successfully altering the orbit of an asteroid. The Dart mission marks the first time humans have changed the motion of a celestial body in space, demonstrating technology that could one day be used to protect Earth."

The scientist and educator Bill Nye said: "We're celebrating ... because a mission like this could save the world."

The Nasa administrator, the former astronaut and Democratic Florida senator Bill Nelson, said: "We showed the world that Nasa is serious as a defender of this planet."

Lori Glaze, director of Nasa's planetary division, said: "Let's all just take a moment to soak this in. We're all here this afternoon because for the first time ever, humanity has changed the orbit of a planetary body."

Andy Lapsa and Tom Feldman, former Blue Origin engineers and the founders of Stoke Space, are working to develop the first fully recyclable space rocket -- one that features a reusable first and second stage. Here's an excerpt from Ars Technica's exclusive report, written by Eric Berger: In the 20 months since its initial seed round of funding, Stoke has built a second-stage engine, a prototype for the second stage, turbopumps, and manufacturing facilities. It also increased its headcount to 72 people and finalized the overall design for the rocket, which has a lift capacity of 1.65 metric tons to low-Earth orbit, in fully reusable mode. Last month, the company started to test-fire its upper-stage engines at a facility in Moses Lake, Washington. The images and video show an intriguing-looking ring with 15 discrete thrusters firing for several seconds. The circular structure is 13 feet in diameter, and this novel-looking design is Stoke's answer to one of the biggest challenges of getting a second stage back from orbit.

Most commonly, a traditional rocket has an upper stage with a single engine. This second-stage rocket engine has a larger nozzle -- often bell-shaped -- to optimize the flow of engine exhaust in a vacuum. Because all parts of a rocket are designed to be as light as possible, such extended nozzles are often fairly fragile because they're only exposed above Earth's atmosphere. So one problem with getting an upper stage back from Earth, especially if you want to use the engine to control and slow its descent, is protecting this large nozzle. One way to do that is to bury the engine nozzle in a large heat shield, but that would require more structure and mass, and it may not be dynamically stable. Stoke's answer was using a ring of 30 smaller thrusters. (The tests last month only employed 15 of the 30 thrusters). In a vacuum, the plumes from these nozzles are designed to merge and act as one. And during reentry, with a smaller number of smaller thrusters firing, it's easier to protect the nozzles. "What you're seeing in the photos of the test is a high-performance upper-stage engine that can operate within atmosphere at deep throttle to support vertical landing but then also perform at a higher ISP than some variants of the RL 10 engine in space," Lapsa said.

Another significant second-stage problem is protecting the whole vehicle from the super-heated atmosphere during reentry. NASA's Space Shuttle accomplished this with brittle thermal tiles, but these required 30,000 employee hours to inspect, test, and refurbish between flights. SpaceX is using a different type of ceramic tile, designed to be more reusable, for Starship. Given Stoke's background in rocket engines, Lapsa said it made the most sense to try a regeneratively cooled heat shield. The vehicle's ductile metallic outer layer will be lined with small cavities to flow propellant through the material to keep it cool during reentry. The second stage, therefore, will return to Earth somewhat like a space capsule -- base first, with the regeneratively cooled heat shield.

Stoke Space has a very long road ahead of it to reach space. Engine tests are an important step, but they're only the first step of many. Next up for the company is "hop" tests with a full-scale version of the second stage at the Moses Lake facility in central Washington. This prototype won't have a fairing as it would during launch, but it will still stand 19 feet tall. Initially, the tests will be low-altitude, probably measured in hundreds of feet. If there's an engineering need to go higher, the company will consider that, Lapsa said. But for now, the goal is to prove the capability to control the rocket during ascent and descent and make a soft landing. This is a shockingly difficult guidance, navigation, and control problem, especially with a novel system of distributed thrusters. "This is kind of a final proof point of this architecture," Lapsa said. "It is new. It's different. It's weird. It's original. There were a lot of questions that we had about how this thing is going to work. But we've already mitigated a lot of risk." If Stoke can manage to land the upper stage, it can move ahead with the first stage and start to turn the yet-unnamed rocket into an orbital vehicle. It sounds easy, but it's not...

Ars Technica's Eric Berger writes: Four days before Thanksgiving in 2002, space shuttle Endeavour lifted off from Kennedy Space Center in Florida. Among the seven crew members to the International Space Station was one Russian cosmonaut, Nikolai M. Budarin, making his third spaceflight. By then, as part of warming relations between Russia and the United States, cosmonauts had been flying on board the space shuttle for nearly a decade. The exchange program would have continued, but tragedy struck on the shuttle's next mission, which launched in January 2003. Space Shuttle Columbia was lost upon reentry into Earth's atmosphere, killing all seven astronauts on board.

Following this disaster, no more Russians would fly on the space shuttle after it returned to service. Instead, NASA focused on flying the minimum number of missions needed to complete the construction of the International Space Station. After the shuttle's retirement in 2011, NASA would come to rely on Russia's Soyuz vehicle as its only ride to space. NASA regained the capacity to launch its own astronauts into space in 2020, after working with SpaceX to complete the development of the Crew Dragon vehicle. Following a successful demonstration flight in May 2020 with two astronauts on board, Crew Dragon safely launched six additional times, carrying an additional two dozen people into space.

On Wednesday, Crew Dragon carried astronauts into space for an eighth time, with the fifth operational mission for NASA. This Crew-5 flight was commanded by Nicole Mann, a NASA astronaut making her first flight into space. "Whooo, that was a smooth ride uphill!" she exclaimed upon reaching orbit. Among the four Dragon riders was a cosmonaut, Anna Kikina, also making her debut flight into space. She is just the sixth Russian or Soviet female cosmonaut in the history of the program since Valentina Tereshkova flew into orbit on June 16, 1963. Kikina is also the first Russian to launch into space from the United States since Budarin, two decades ago. In addition to Mann and Kikina, Crew-5 is rounded out by NASA astronaut Josh Cassada and Japanese astronaut Koichi Wakata. While the other three are rookies, this is Wakata's fifth spaceflight. During their stay aboard the International Space Station, the astronauts will conduct more than 200 science experiments and technology demonstrations, including studies on printing human organs in space.

NASA says the damage to their launch facilities in Florida following Hurricane Ian was minimal and work was already underway for a "rapid-fire succession of three launches in three days," reports Ars Technica. An anonymous reader shares an excerpt from the report: First up is a commercial mission on United Launch Alliance's Atlas V rocket to launch SES-20 and SES-21 satellites for Luxembourg-based satellite operator SES. Stacked in its '531' configuration, this Atlas rocket has a five-meter-diameter payload fairing, three solid rocket boosters, and one engine on the upper-stage Centaur. On Friday, United Launch Alliance said everything continues to progress toward the launch of this mission on Tuesday, October 4, from Space Launch Complex-41 at Cape Canaveral Space Force Station. The launch is planned for 5:36 pm EST (21:36 UTC). Weather is forecast to be favorable, with a 70 percent chance of favorable conditions for launch. After launching, the Atlas V rocket will deliver the pair of communications satellites into near-circular, near-geosynchronous orbits. Once separated, the satellites will use onboard propulsion systems to circularize their orbits at 35,900 km above the equator.

Next up in Florida is NASA's Crew-5 mission, which will launch on a Falcon 9 rocket to the International Space Station. NASA officials confirmed this mission remains on schedule for noon EST (16:00 UTC) on October 5 from Launch Complex-39A at Kennedy Space Center. The crew of four -- NASA astronauts Nicole Mann and Josh Cassada, Japan Aerospace Exploration Agency astronaut Koichi Wakata, and Roscosmos cosmonaut Anna Kikina -- have been holding at Johnson Space Center in Houston pending the outcome of Hurricane Ian. However, they will now fly to Florida on Saturday in preparation for the launch. SpaceX, meanwhile, will roll its Falcon 9 rocket with the Crew Dragon spacecraft to the launchpad on Friday night or Saturday, ahead of a static fire test on Sunday. There appear to be no significant technical issues to be worked on ahead of the launch next Wednesday.

Finally, on October 6, SpaceX plans an additional launch. For this mission, from Space Launch Complex-40 at Cape Canaveral, a Falcon 9 rocket will deliver Intelsat's Galaxy 33 and 34 satellites telecommunications satellites into a geostationary transfer orbit. The launch is set for 7:07 pm EST (23:07 UTC). Of note for this mission, this Falcon 9 first-stage booster will be making its 14th launch. This marks the first time a SpaceX rocket has flown a purely commercial payload on its 10th flight or later. This strongly suggests that the commercial satellite market is becoming increasingly comfortable with SpaceX's refurbishment process for even well-used rockets. Additionally, NASA said that its Artemis I hardware "survived Hurricane Ian just fine, safely tucked inside the large Vehicle Assembly Building at Kennedy Space Center," notes Ars. "The agency will aim to have the rocket ready for a launch attempt in about six weeks."

techmage writes: Early this morning, Firefly Aerospace succeeded in launching their Alpha rocket to Low Earth Orbit. This marks one of a handful of companies who have reached space with that few attempts (Virgin Orbit and RocketLab are just some of the others).

Shameless plug -- I had the pleasure of building the Serenity satellite, a 3U CubeSat that flew on the mission.

Check out the video of the launch and deployment. It is quite something to watch. All three payloads were successfully deployed. Space.com reports: One of them, called Serenity, comes from the nonprofit organization Teachers in Space. Serenity was designed to collect a variety of data during today's flight, which will be shared with the educational community, according to a Firefly mission description.

Also reaching orbit today was TechEdSat-15 (TES-15), which is owned by NASA in coordination with San Jose State University in California. TES-15 features an "exo-brake" designed to help satellites leave their orbital perches more smoothly when their work is done. "The exo-brake will deploy after the cubesat is ejected from its dispenser to deorbit the cubesat," Firefly wrote in the mission description. TES-15 also carries an experiment designed to optimize data transfer from the little spacecraft, the company added.

The third payload -- the PicoBus deployer, from the nonprofit Libre Space -- carries five tiny payloads of its own. Those bantam "picosats" include Genesis-L & Genesis-N, from AMSAT (Radio Amateur Satellite Corporation) Spain. The pair will demonstrate a pulsed-plasma thruster system for spacecraft propulsion and "build heritage for future missions," according to Firefly. PicoBus is also carrying Libre Space's Qubik-1 and Qubik-2, which will perform communications experiments, and FossaSat-1B. This latter satellite, from the Spanish company Fossa Systems, will test communications and remote-sensing tech. It also carries a low-resolution Earth-imaging camera.

An anonymous reader quotes a report from Wired: Over the past eight years, a modified Boeing 747 jetliner has flown hundreds of flights on a unique mission: carrying a 19-ton, 2.5-meter telescope known as Sofia, or the Stratospheric Observatory for Infrared Astronomy. Flying a telescope on a jumbo jet offered a way to peer into the heavens at wavelengths that could not be glimpsed from the ground -- but the ticket was expensive. So yesterday, NASA and the German space agency grounded the mission. Its final flight landed early Thursday morning at NASA's Armstrong Flight Research Center in the desert near Los Angeles.

Sofia was an innovative way to gaze at the infrared universe. Infrared light is essentially heat radiation -- but astronomers can't probe cosmic objects like dust-enshrouded stars and galaxies without the water vapor in Earth's atmosphere absorbing that light. That confounds attempts to observe those objects with telescopes built on mountaintops, like the observatories in Hawaii and Chile. But by soaring through the stratosphere, at an elevation of 40,000 feet or higher, Sofia could fly above that water vapor and get a much better view. "Almost 50 percent of the energy of the universe comes out in the mid- to far infrared. Sofia has played an important and unique role for its lifetime, probing that entire wavelength range, and we've been able to observe all manner of phenomena that were otherwise invisible to other facilities," says Jim De Buizer, Sofia senior scientist at NASA's Ames Research Center in Mountain View, California.

De Buizer and the Sofia team have made a number of significant astronomical discoveries, including measuring cosmic magnetic fields permeating nearby galaxies, charting the growth of massive stars, observing Pluto's faint shadow as it passed in front of a distant star, and even discovering water on the sunlit surface of the moon's southern hemisphere. The data from Sofia's final flight will map stellar nebulas and help scientists study the magnetic fields of the Sculptor starburst galaxy. But while flying a telescope in a jet is much less expensive than launching one aboard a spacecraft, like NASA's Spitzer and Webb space telescopes and the European Space Agency's Herschel Space Observatory, it's still not cheap. There are costs for the pilots, staff, engineers, and mechanics -- plus a round of repairs to the aircraft that had to be made in 2018. Sofia costs NASA about $85 million per year -- a significant fraction of its astrophysics budget. And that's actually only 80 percent of the funding it needs; NASA's German counterparts provided the rest. It was ultimately the mission's high operating costs, relative to its scientific output, that took Sofia down. "At the end of the day, the project itself just wasn't productive. You're talking about almost a Hubble cost for operations, but with a fraction of the scientific productivity," says Casey Dreier, senior space policy adviser for the Planetary Society, a nonprofit research organization based in Pasadena, California.

"I feel for the scientists. They can't control the operational costs," Dreier says. "But Sofia got eight years of operations. It had a good, healthy life, for a mission."

NASA announced Thursday that it plans to study the possibility of using SpaceX's Crew Dragon vehicle to boost the aging Hubble Space Telescope into a higher orbit. Ars Technica reports: The federal agency has signed a "Space Act Agreement" with SpaceX to conduct a six-month study to determine the practicability of Dragon docking with the 32-year-old telescope and boosting it into a higher orbit. The study is not exclusive, meaning that other companies can propose similar concepts with alternative rockets and spacecraft. [...] Among the questions the new Hubble study will answer is the cost of such a mission and its technical feasibility. The principal goal is to boost Hubble's altitude from its current level of 535 km to 600 km, the same altitude it was at when first launched in 1990. Since the fifth and final servicing mission in 2009, Hubble has slowly been losing altitude, and this process is expected to accelerate as the telescope gets lower.

The telescope's project manager, Patrick Crouse, said during a teleconference with reporters that in absence of a re-boost mission, NASA might have to launch a propulsion module to the telescope by the end of the 2020s. This would ensure Hubble makes a controlled reentry into Earth's atmosphere and lands in the Pacific Ocean. A Dragon mission to boost Hubble's altitude could add 15 or even 20 years of orbital lifetime, Crouse said. The study will also look at potential servicing options, although nothing like the detailed instrument replacements and major upgrades performed during Hubble servicing missions with NASA's space shuttle. Rather, engineers from NASA and SpaceX will assess the feasibility of replacing the gyroscopes that control the pointing of the telescope. Only three of the spacecraft's six gyroscopes remain in working order.

NASA's Juno spacecraft has made the closest approach to Jupiter's tantalizing, icy moon Europa in more than 20 years. From a report: Juno on Thursday zipped within 222 miles (357 kilometers) of Europa, thought to have an ocean flowing beneath its thick frozen crust, raising the possibility of underwater life. Scientists hope to get lucky and observe possible water plumes shooting from the surface of Europa, close in size to Earth's moon. "We have to be at the right place at just the right time, but if we are so fortunate, it's a home run for sure," Juno's chief scientist, Scott Bolton of Southwest Research Institute in San Antonio, said in a statement. John Bordi, deputy mission manager at NASA's Jet Propulsion Laboratory, expected the spacecraft to go "screaming by pretty fast," with a relative velocity of almost 15 miles per second (23.6 kilometers per second). Pictures should be available by Friday, NASA said. The latest observations will help NASA plan for its Europa Clipper mission, due to launch in 2024. The European Space Agency also plans close encounters with its Jupiter Icy Moons Explorer, or Juice, lifting off next year.

NASA's DART spacecraft successfully slammed into a distant asteroid at hypersonic speed on Monday in the world's first test of a planetary defense system, designed to prevent a potential doomsday meteorite collision with Earth. From a report: Humanity's first attempt to alter the motion of an asteroid or any celestial body played out in a NASA webcast from the mission operations center outside Washington, D.C., 10 months after DART was launched. The livestream showed images taken by DART's camera as the cube-shaped "impactor" vehicle, no bigger than a vending machine with two rectangular solar arrays, streaked into the asteroid Dimorphos, about the size of a football stadium, at 7:14 p.m. EDT (2314 GMT) some 6.8 million miles (11 million km) from Earth. The $330 million mission, some seven years in development, was devised to determine if a spacecraft is capable of changing the trajectory of an asteroid through sheer kinetic force, nudging it off course just enough to keep Earth out of harm's way. Whether the experiment succeeded beyond accomplishing its intended impact will not be known until further ground-based telescope observations of the asteroid next month. But NASA officials hailed the immediate outcome of Monday's test, saying the spacecraft achieved its purpose.

Noam Izenberg, a researcher at the Johns Hopkins University's applied physics laboratory, is making a case for sending a crewed mission to examine Venus en route to Mars. "Venus gets a bad rap because it's got such a difficult surface environment," said Izenberg in a report presented at the International Astronautical Congress in Paris last week. "The current Nasa paradigm is moon-to-Mars. We're trying to make the case for Venus as an additional target on that pathway." The Guardian reports: There are notable downsides. Walking on the surface would be an unsurvivable experience, so astronauts would have to gaze down at the planet from the safety of their spacecraft in a flyby mission. In its favor, however, Venus is significantly closer, making a return mission doable in a year, compared with a potentially three-year roundtrip to Mars. A flyby would be scientifically valuable and could provide crucial experience of a lengthy deep-space mission as a precursor to visiting Mars, according to a report presented at the International Astronautical Congress (IAC) in Paris last week.

Izenberg said there were practical arguments for incorporating a Venus flyby into the crewed Mars landing that Nasa hopes to achieve by the late 2030s. Although the planet is in the "wrong" direction, performing a slingshot around Venus -- known as a gravity assist - could reduce the travel time and the fuel required to get to the red planet. That would make a crewed flyby trip to Venus a natural stepping stone towards Nasa's ultimate goal. "You'd be learning about how people work in deep space, without committing yourself to a full Mars mission," he said. "And it's not just going out into the middle of nowhere -- it would have a bit of cachet as you'd be visiting another planet for the first time." "We need to understand how we can get out of the cradle and move into the universe," he added.

There is also renewed scientific interest in Venus. The discovery of thousands of exoplanets raises the question of how many might be habitable, and scientists want to understand how and why Venus, a planet so similar to our own in size, mass and distance from the sun, ended up with infernal surface conditions. Izenberg said a Venus flyby "doesn't yet have traction" in the broader space travel community, although there are advocates within Nasa, including its chief economist, Alexander Macdonald, who led the IAC session. Of course, there are those who push back against such an idea. "It's really not a nice place to go. It's a hellish environment and the thermal challenges for a human mission would be quite considerable," said Prof Andrew Coates, a space scientist at UCL's Mullard space science laboratory.

He said Venus was rightly a focus of scientific exploration, but that "a human flyby really wouldn't add very much."

Most mission scientists would wince at the thought of their spacecraft being smashed to smithereens. But for those behind Nasa's Dart probe, anything short of total destruction will be chalked up as a failure. From a report: The $330m spacecraft is due to slam head-on into an asteroid about 11m kilometres above the Indian Ocean soon after midnight on Monday. The impact, at nearly seven kilometres a second, will obliterate the half-tonne probe, all in the name of planetary defence. Not that Dimorphos, the asteroid in question, poses any threat to humanity. The Dart, or double asteroid redirection test, is an experiment, the first mission ever to assess whether asteroids can be deflected should one ever be found on a collision course with Earth. A well-placed nudge could avert Armageddon, or so the thinking goes, and spare humans the same fate as the dinosaurs.

"It's a very complicated game of cosmic billiards," said Prof Alan Fitzsimmons, an astronomer and member of the Nasa Dart investigation team at Queen's University Belfast. "What we want to do is use as much energy [as we can] from Dart to move the asteroid." With telescopes constantly scanning the skies, scientists hope to have some notice if an asteroid were ever to present a major threat. "If we are able to see far enough in advance and know that an asteroid might be a problem, pushing it out of the way will be much safer than the big Hollywood idea of blowing it up," said Catriona McDonald, a PhD student at Warwick University. The Dart mission launched from Vandenberg space force base in November last year. On Monday night, mission controllers will hand control to Dart's software and let the probe steer itself into oblivion.

The Artemis I rocket will not have its third launch attempt on Tuesday as planned due to concerns over Tropical Storm Ian making its way toward Cuba and Florida. CNN reports: After meeting on Saturday morning, NASA's Artemis team decided to forgo the September 27 launch opportunity and is now preparing the mega moon rocket stack for rollback. "On Tuesday, Tropical Storm Ian is forecast to be moving north through the eastern Gulf of Mexico as a hurricane, just off the southwest coast of Florida. A cold front will also be draped across northern Florida pushing south," said CNN Meteorologist Haley Brink.

"The combination of these weather factors will allow for increased rain chances across much of the Florida peninsula on Tuesday, including the Cape Canaveral area. Showers and thunderstorms are forecast to be numerous and widespread across the region. Tropical storm-force winds from Ian could also arrive as early as Tuesday night across central Florida." Meanwhile, the Space Launch System rocket and Orion spacecraft continue to sit on the launchpad at Kennedy Space Center in Florida.

Team members continue to monitor the weather as they make a decision about when to roll the rocket stack back into the Vehicle Assembly Building at Kennedy. NASA will receive information from the US Space Force, the National Hurricane Center and the National Oceanic and Atmospheric Administration to inform their decision. [...] The rocket stack can remain at the pad and withstand winds up to 85 miles per hour (74.1 knots). If the stack needs to roll back into the building, it can handle sustained winds less than 46 miles per hour (40 knots). On Friday, the Artemis team said that October 2 was a backup launch date. But it's unlikely that a new launch date will be set until the rollback decision has been made.

An anonymous reader quotes a report from Ars Technica: In January this year, an undersea volcano in Tonga produced a massive eruption, the largest so far this century. The mixing of hot volcanic material and cool ocean water created an explosion that sent an atmospheric shockwave across the planet and triggered a tsunami that devastated local communities and reached as far as Japan. The only part of the crater's rim that extended above water was reduced in size and separated into two islands. A plume of material was blasted straight through the stratosphere and into the mesosphere, over 50 km above the Earth's surface. We've taken a good look at a number of past volcanic eruptions and studied how they influence the climate. But those eruptions (most notably that of Mount Pinatubo) all came from volcanoes on land. Hunga Tonga may be the largest eruption we've ever documented that took place under water, and the eruption plume contained unusual amounts of water vapor -- so much of it that it actually got in the way of satellite observations at some wavelengths. Now, researchers have used weather balloon data to reconstruct the plume and follow its progress during two circuits around the globe.

Your vocabulary word of the day is radiosonde, which is a small instrument package and transmitter that can be carried into the atmosphere by a weather balloon. There are networks of sites where radiosondes are launched as part of weather forecasting services; the most relevant ones for Hunga Tonga are in Fiji and Eastern Australia. A balloon from Fiji was the first to take instruments into the eruption plume, doing so less than 24 hours after Hunga Tonga exploded. That radiosonde saw increasing levels of water as it climbed through the stratosphere from 19 to 28 kilometers of altitude. The water levels had reached the highest yet measured at the top of that range when the balloon burst, bringing an end to the measurements. But shortly after, the plume started showing up along the east coast of Australia, which again registered very high levels of water vapor. Again, water reached to 28 km in altitude but gradually settled to lower heights over the next 24 hours.

The striking thing was how much of it there was. Compared to normal background levels of stratospheric water vapor, these radiosondes were registering 580 times as much water even two days after the eruption, after the plume had some time to spread out. There was so much there that it still stood out as the plume drifted over South America. The researchers were able to track it for a total of six weeks, following it as it spread out while circling the Earth twice. Using some of these readings, the researchers estimated the total volume of the water vapor plume and then used the levels of water present to come up with a total amount of water put into the stratosphere by the eruption. They came up with 50 billion kilograms. And that's a low estimate, because, as mentioned above, there was still water above the altitudes where some of the measurements stopped. The recent findings appear in a new study published in the journal Science.

A pair of researchers who previously identified what may be the first known interstellar meteor to impact Earth have now presented evidence of a second object that could have originated beyond the solar system, before it burned up in our planet's skies and potentially fell to the surface, according to a new study. Motherboard reports: Amir Siraj, a student in astrophysics at Harvard University, and astronomer Avi Loeb, who serves as Harvard's Frank B. Baird Jr. Professor of Science, suggest that a fast-moving meteor that burst into a fireball hundreds of miles off the coast of Portugal on March 9, 2017, is an "additional interstellar object candidate" that they call interstellar meteor 2 (IM2) in a study posted to the preprint server arXiv this week. The paper has not been peer-reviewed. In addition to their potential origin beyond the solar system, these objects appear to be extraordinarily robust, as they rank as the first- and third-highest meteors in material strength in a NASA catalog that has collected data about hundreds of fireballs.

"We don't have a large enough sample to say how much stronger interstellar objects are than solar system objects, but we can say that they are stronger," Siraj said in an email. "The odds of randomly drawing two objects in the top 3 out of 273 is 1 in 10 thousand. And when we look at the specific numbers relative to the distribution of objects, we find that the Gaussian odds are more like 1 in a million." This makes IM2 "an outlier in material strength," Loeb added in a follow-up call with Siraj. "To us, it means that the source is different from planetary systems like the solar system."

Loeb has attracted widespread attention in recent years over his speculation that the first interstellar object ever identified, known as 'Oumuamua, was an artifact of alien technology. Spotted in 2017, 'Oumuamua sped through the solar system and was up to a quarter-mile in scale, making it much larger than the interstellar meteor candidates identified by Siraj and Loeb, which are a few feet across. Loeb's claims of an artificial origin for 'Oumuamua have provoked substantial pushback from many scientists who do not consider a technological explanation to be likely. Loeb also thinks these interstellar meteor candidates could be alien artifacts, though he and Siraj present a mind-boggling natural explanation for the strangely robust objects in the study: The meteors may be a kind of interstellar shrapnel produced by the explosions of large stars, called supernovae. [...] Loeb, of course, is keeping his mind open. "We don't say, necessarily, that it is artificial," Loeb said in the call, referring to the supernovae explanation. But, he added, "obviously, there is a possibility that a spacecraft was designed to sustain such harsh conditions as passing through the Earth's atmosphere, so we should allow for that."

According to NASA, the James Webb Space Telescope has captured the clearest view of Neptune's rings in more than 30 years. From the report: Most striking in Webb's new image is the crisp view of the planet's rings -- some of which have not been detected since NASA's Voyager 2 became the first spacecraft to observe Neptune during its flyby in 1989. In addition to several bright, narrow rings, the Webb image clearly shows Neptune's fainter dust bands. "It has been three decades since we last saw these faint, dusty rings, and this is the first time we've seen them in the infrared," notes Heidi Hammel, a Neptune system expert and interdisciplinary scientist for Webb. Webb's extremely stable and precise image quality permits these very faint rings to be detected so close to Neptune.

Webb's Near-Infrared Camera (NIRCam) images objects in the near-infrared range from 0.6 to 5 microns, so Neptune does not appear blue to Webb. In fact, the methane gas so strongly absorbs red and infrared light that the planet is quite dark at these near-infrared wavelengths, except where high-altitude clouds are present. Such methane-ice clouds are prominent as bright streaks and spots, which reflect sunlight before it is absorbed by methane gas. Images from other observatories, including the Hubble Space Telescope and the W.M. Keck Observatory, have recorded these rapidly evolving cloud features over the years. More subtly, a thin line of brightness circling the planet's equator could be a visual signature of global atmospheric circulation that powers Neptune's winds and storms. The atmosphere descends and warms at the equator, and thus glows at infrared wavelengths more than the surrounding, cooler gases.

Neptune's 164-year orbit means its northern pole, at the top of this image, is just out of view for astronomers, but the Webb images hint at an intriguing brightness in that area. A previously-known vortex at the southern pole is evident in Webb's view, but for the first time Webb has revealed a continuous band of high-latitude clouds surrounding it. Webb also captured seven of Neptune's 14 known moons. Dominating this Webb portrait of Neptune is a very bright point of light sporting the signature diffraction spikes seen in many of Webb's images, but this is not a star. Rather, this is Neptune's large and unusual moon, Triton.