On March 23, sky observers marveled at a gorgeous display of northern and southern lights. It was a reminder that when our Sun gets active, it can spark a phenomenon called “space weather.” Aurorae are among the most benign effects of this phenomenon. At the other end of the space weather spectrum are solar storms that can knock out satellites. The folks at Starlink found that out the hard way in February 2022. On January 29 that year, the Sun belched out a class M 1.1 flare and related coronal mass ejection. Material from the Sun traveled out on the solar wind and arrived at Earth a few days later. On February 3, Starlink launched a group of 49 satellites to an altitude only 130 miles above Earth’s surface. They didn’t last long, and now solar physicists know why.

A group of researchers from NASA Goddard Space Flight Center and the Catholic University of America took a closer look at the specifics of that storm. Their analysis identified a mass of plasma that impacted our planet’s magnetosphere. The actual event was a halo coronal mass ejection from an active region in the northeast quadrant of the Sun. The material traveled out at around 690 kilometers per second as a shock-driving magnetic cloud. Think of it as a long ropy mass of material writhing its way through space. As it traveled, it expanded and at solar-facing satellites — including STEREO-A, which took a direct hit from it — made observations. Eventually, the cloud smacked into Earth’s magnetosphere creating a geomagnetic storm.

The atmosphere thickened enough that it affected the newly launched Starlink stations. They started to experience atmospheric drag, which caused them to deorbit and burn up on the way down. It was an expensive lesson in space weather and provided people on Earth with a great view of what happens when satellites fall back to Earth. It was also that could have been avoided if they’d delayed their launch to account for the ongoing threat.

Source: NASA Reveals What Made an Entire Starlink Satellite Fleet Go Down – Slashdot

There’s an invisible monster on the loose, barreling through intergalactic space so fast that if it were in our solar system, it could travel from Earth to the Moon in 14 minutes. This supermassive black hole, weighing as much as 20 million Suns, has left behind a never-before-seen 200,000-light-year-long “contrail” of newborn stars, twice the diameter of our Milky Way galaxy. It’s likely the result of a rare, bizarre game of galactic billiards among three massive black holes.

Rather than gobbling up stars ahead of it, like a cosmic Pac-Man, the speedy black hole is plowing into gas in front of it to trigger new star formation along a narrow corridor. The black hole is streaking too fast to take time for a snack. Nothing like it has ever been seen before, but it was captured accidentally by NASA’s Hubble Space Telescope.

This is an artist’s impression of a runaway supermassive black hole that was ejected from its host galaxy as a result of a tussle between it and two other black holes. As the black hole plows through intergalactic space it compresses tenuous gas in front to it. This precipitates the birth of hot blue stars. This illustration is based on Hubble Space Telescope observations of a 200,000-light-year-long “contrail” of stars behind an escaping black hole. For more details, read the Extended Text Description.

Credits: NASA, ESA, Leah Hustak (STScI)

“We think we’re seeing a wake behind the black hole where the gas cools and is able to form stars. So, we’re looking at star formation trailing the black hole,” said Pieter van Dokkum of Yale University in New Haven, Connecticut. “What we’re seeing is the aftermath. Like the wake behind a ship we’re seeing the wake behind the black hole.” The trail must have lots of new stars, given that it is almost half as bright as the host galaxy it is linked to.

The black hole lies at one end of the column, which stretches back to its parent galaxy. There is a remarkably bright knot of ionized oxygen at the outermost tip of the column. Researchers believe gas is probably being shocked and heated from the motion of the black hole hitting the gas, or it could be radiation from an accretion disk around the black hole. “Gas in front of it gets shocked because of this supersonic, very high-velocity impact of the black hole moving through the gas. How it works exactly is not really known,” said van Dokkum.

“This is pure serendipity that we stumbled across it,” van Dokkum added. He was looking for globular star clusters in a nearby dwarf galaxy. “I was just scanning through the Hubble image and then I noticed that we have a little streak. I immediately thought, ‘oh, a cosmic ray hitting the camera detector and causing a linear imaging artifact.’ When we eliminated cosmic rays we realized it was still there. It didn’t look like anything we’ve seen before.”

This Hubble Space Telescope archival photo captures a curious linear feature that is so unusual it was first dismissed as an imaging artifact from Hubble’s cameras. But follow-up spectroscopic observations reveal it is a 200,000-light-year-long chain of young blue stars. A supermassive black hole lies at the tip of the bridge at lower left. The black hole was ejected from the galaxy at upper right. It compressed gas in its wake to leave a long trail of young blue stars. Nothing like this has ever been seen before in the universe. This unusual event happened when the universe was approximately half its current age.

Credits: NASA, ESA, Pieter van Dokkum (Yale); Image Processing: Joseph DePasquale (STScI)

Because it was so weird, van Dokkum and his team did follow-up spectroscopy with the W. M. Keck Observatories in Hawaii. He describes the star trail as “quite astonishing, very, very bright and very unusual.” This led to the conclusion that he was looking at the aftermath of a black hole flying through a halo of gas surrounding the host galaxy.

This intergalactic skyrocket is likely the result of multiple collisions of supermassive black holes. Astronomers suspect the first two galaxies merged perhaps 50 million years ago. That brought together two supermassive black holes at their centers. They whirled around each other as a binary black hole.

Then another galaxy came along with its own supermassive black hole. This follows the old idiom: “two’s company and three’s a crowd.” The three black holes mixing it up led to a chaotic and unstable configuration. One of the black holes robbed momentum from the other two black holes and got thrown out of the host galaxy. The original binary may have remained intact, or the new interloper black hole may have replaced one of the two that were in the original binary, and kicked out the previous companion.

When the single black hole took off in one direction, the binary black holes shot off in the opposite direction. There is a feature seen on the opposite side of the host galaxy that might be the runaway binary black hole. Circumstantial evidence for this is that there is no sign of an active black hole remaining at the galaxy’s core. The next step is to do follow-up observations with NASA’s James Webb Space Telescope and the Chandra X-ray Observatory to confirm the black hole explanation.

There’s an invisible monster on the loose! It’s barreling through intergalactic space fast enough to travel from Earth to the Moon in 14 minutes. But don’t worry, luckily this beast is very, very far away! This potential supermassive black hole, weighing as much as 20 million Suns, has left behind a never-before-seen 200,000 light-year-long trail of newborn stars. The streamer is twice the diameter of our Milky Way galaxy. It’s likely the result of a rare, bizarre game of galactic billiards among three massive black holes.

Credits: NASA’s Goddard Space Flight Center; Lead Producer: Paul Morris

NASA’s upcoming Nancy Grace Roman Space Telescope will have a wide-angle view of the universe with Hubble’s exquisite resolution. As a survey telescope, the Roman observations might find more of these rare and improbable “star streaks” elsewhere in the universe. This may require machine learning using algorithms that are very good at finding specific weird shapes in a sea of other astronomical data, according to van Dokkum.

The research paper will be published on April 6 in The Astrophysical Journal Letters.

https://www.nasa.gov/feature/goddard/2023/hubble-sees-possible-runaway-black-hole-creating-a-trail-of-stars

The Bruce Murray Laboratory for Planetary Visualization has completed a 5.7 terapixel mosaic of the surface of Mars rendered at 5.0 m/px. Each pixel in the mosaic is about the size of a typical parking space, providing unprecedented resolution of the martian surface at the global scale.

The mosaic covers 99.5% of Mars from 88°S to 88°N. The pixels that make up the mosaic can all be mapped back to their source data, providing full traceability for the entire mosaic. The mosaic is available to stream over the internet and to download, as described below.

All data in the mosaic come from the Context Camera (CTX) onboard the Mars Reconnaissance Orbiter (MRO).

Below is the entire mosaic within a 3D viewer. Click “See the Mosaic in 3D,” or click here to see it in a new window.

https://murray-lab.caltech.edu/CTX/

[…]

Some of the data was mistaken as noise when first collected up to 40 years ago, and researchers failed to recognize its significance until now. “When everything was calibrated, we saw clearly that the spectra are consistent across all the missions,” announced Lotfi Ben-Jaffel, lead author of the new research published in Planetary Science Journal on Thursday, and a researcher at the Institute of Astrophysics in Paris and the Lunar & Planetary Laboratory, University of Arizona, in a statement.

“This was possible because we have the same reference point, from Hubble, on the rate of transfer of energy from the atmosphere as measured over decades. It was really a surprise for me. I just plotted the different light distribution data together, and then I realized, wow – it’s the same.”

The researchers traced the increased levels of Lyman-alpha UV radiation to Saturn’s atmosphere, and concluded some external process must be exciting the hydrogen atoms. The most plausible explanation is that the icy particles in Saturn’s rings are crashing down onto Saturn’s atmosphere, causing it to heat up.

These bits and pieces get dislodged by colliding with micrometeorites, or by solar wind particle bombardment, solar ultraviolet radiation, or electromagnetic forces picking up electrically charged dust. Once they are knocked out of place, Saturn’s gravity pulls them in.

“Though the slow disintegration of the rings is well known, its influence on the atomic hydrogen of the planet is a surprise,” Ben-Jaffel said. “From the Cassini probe, we already knew about the rings’ influence. However, we knew nothing about the atomic hydrogen content.”

“Everything is driven by ring particles cascading into the atmosphere at specific latitudes. They modify the upper atmosphere, changing the composition. And then you also have collisional processes with atmospheric gases that are probably heating the atmosphere at a specific altitude,” he explained.

The team believe this phenomenon could provide astronomers with a new way to look for ring systems on exoplanets. If a spacecraft detects similar excess UV radiation bands in the upper atmosphere of a faraway planet, it could mean it might be supporting a ring system like Saturn’s.

[…]

Source: Astronomers discover never-before-seen phenomenon on Saturn • The Register

Virgin Orbit’s days of slinging satellites into space aboard aircraft-launched rockets have come to an end Thursday. After six years in business, Virgin’s satellite launch subsidiary has announced via SEC filing that it does not have the funding to continue operations and will be shuttering for “the foreseeable future,” per CNBC. Nearly 90 percent of Virgin Orbit’s employees — 675 people in total — will be laid off immediately.

Virgin Orbit was founded in 2017 for the purpose of developing and commercializing LauncherOne, a satellite launch system fitted under a modified 747 airliner, dubbed Cosmic Girl. The system was designed to put 500 pounds of cubesats into Low Earth Orbit by firing them in a rocket from said airliner flying at an altitude of 30,000 – 50,000 feet. Despite a string of early successes — both in terms of development milestones and expanding service contracts with the UK military, LauncherOne’s first official test in May of 2020 failed to deliver its simulated payload into orbit.

A second attempt the following January in 2022 however was a success with the launch of 10 NASA cube sats into LEO, as was Virgin Orbit’s first commercial satellite launch that June. It successfully sent seven more satellites into orbit in January 2022 and quietly launched Space Force assets that July.

In all, Virgin Orbit made six total flights between 2020 and 2023, only four successfully. The most recent attempt was dubbed the Start Me Up event and was supposed to mark the first commercial space launch from UK soil. Despite the rocket successfully separating from its parent aircraft, an upper stage “anomaly” prevented the rocket’s payload from entering orbit. It was later determined that a $100 fuel filter had failed and resulted in the fault.

As TechCrunch points out, Virgin Group founder, Sir Richard Branson, “threw upwards of $55 million to the sinking space company,” in recent months but Start Me Up’s embarrassing failure turned out to be the final straw. On March 16th, Virgin Orbit announced an “operational pause” and worker furlough for its roughly 750 employees as company leadership scrambled to find new funding sources. The company extended the furlough two weeks later and called it quits on Thursday.

“Unfortunately, we’ve not been able to secure the funding to provide a clear path for this company,” Virgin CEO Dan Hart said in an all-hands call obtained by CNBC. “We have no choice but to implement immediate, dramatic and extremely painful changes.”

Impacted employees will reportedly receive severance packages, according to Hart, including a cash payment, continued benefits and a “direct pipeline” to Virgin Galactic’s hiring department. Virgin Orbit’s two top executives will also receive “golden parachute” severances which were approved by the company’s board, conveniently, back in mid-March right when the furloughs first took effect.

Source: Virgin Orbit officially shutters its space launch operations | Engadget

Dawn Aerospace CEO Stefan Powell announced today that the company’s Mk-II Aurora spaceplane has received approval from the Civil Aviation Authority of New Zealand for rocket-powered flight. The company is now ready to test the vehicle’s rocket engines with flights beginning next month.

The Mk-II Aurora is a remotely piloted spaceplane that could eventually take two trips into space every day. During testing, the Mk-II will host research projects and collect scientific data with its onboard 3U payload capacity (i.e. 30 cubic centimeters in size) while serving as a proof of concept for a later model—the Mk-III—that could deliver 550-pound (250-kilogram) satellites into orbit with the help of a second stage rocket (the concept is somewhat similar to how Virgin Orbit uses piloted aircraft to deploy its LauncherOne rocket).

With approval from New Zealand’s Civil Aviation Authority, Dawn Aerospace is readying to begin rocket-powered flight tests of the Mk-II Aurora beginning in just a few weeks. The company has already fired the Aurora’s rocket engine—112 times according to Powell in a press release—but never has it conducted a flight test with the engine, opting to flight test 48 times with jet engines instead.

[…]

tests of the Mk-II Aurora will follow a “build-up approach,” as previous testing has, in which the plane will reach “modest” altitudes and speeds to demonstrate that rocket-powered flight is just as viable as commercial aircraft.

The altitude the Aurora will reach in these upcoming tests isn’t necessarily modest, as company plans to reach the internationally recognized boundary of space, better known as the Karman line. As SatNews reported last September, Dawn Aerospace is gearing up for Phase 2 of testing the Aurora, which according to its company’s website, will see the company push Aurora to higher and higher altitudes over a series of tests until it crosses the Karman line, which is about 62 miles (100 kilometers) above the Earth’s surface.

Source: New Zealand’s Spaceplane Approved for Suborbital Test Flights

[…]

The Drag Augmentation Deorbiting System (ADEO) braking sail was developed by High Performance Space Structure Systems as a way to deorbit satellites at the end of their mission. In a space-based test in December 2022 called “Show Me Your Wings,” ADEO was deployed from an ION Satellite Carrier built by private space company D-Orbit. ADEO successfully pushed the satellite carrier out of its orbit, sending it into the atmosphere to burn up.

[…]

“We want to establish a zero debris policy, which means if you bring a spacecraft into orbit you have to remove it,” said ESA Director General Josef Aschbacher in a press release.

ADEO – Deorbit Sailing on Angel Wings

ADEO is a 38-square-foot (3.5-square-meter) sail made up of an aluminum-coated polyamide membrane secured to four carbon-fibre reinforced arms that are positioned in an X-shape. The sail increases surface drag when deployed from a satellite, leading to a more rapidly decaying orbit. ADEO can also be scaled up or down depending on the size of the satellite it’s attached to. The largest version could reach 1,076-square-feet (100-square-meter) with the smallest sail being 37-square-foot (3.5-square-meter).

[…]

Source: Space Sail Experiment Expedites Disposal of Satellite

Hundreds of millions of light-years away in a distant galaxy, a star orbiting a supermassive black hole is being violently ripped apart under the black hole’s immense gravitational pull. As the star is shredded, its remnants are transformed into a stream of debris that rains back down onto the black hole to form a very hot, very bright disk of material swirling around the black hole, called an accretion disc. This phenomenon—where a star is destroyed by a supermassive black hole and fuels a luminous accretion flare—is known as a tidal disruption event (TDE), and it is predicted that TDEs occur roughly once every 10,000 to 100,000 years in a given galaxy.

[…]

TDEs are usually “once-and-done” because the extreme gravitational field of the SMBH destroys the star, meaning that the SMBH fades back into darkness following the accretion flare. In some instances, however, the high-density core of the star can survive the gravitational interaction with the SMBH, allowing it to orbit the black hole more than once. Researchers call this a repeating partial TDE.

[…]

findings, published in Astrophysical Journal Letters, describe the capture of the star by a SMBH, the stripping of the material each time the star comes close to the black hole, and the delay between when the material is stripped and when it feeds the black hole again.

[…]

Once bound to the SMBH, the star powering the emission from AT2018fyk has been repeatedly stripped of its outer envelope each time it passes through its point of closest approach with the black hole. The stripped outer layers of the star form the bright accretion disk, which researchers can study using X-Ray and Ultraviolet /Optical telescopes that observe light from distant galaxies.

[…]

“Until now, the assumption has been that when we see the aftermath of a close encounter between a star and a supermassive black hole, the outcome will be fatal for the star, that is, the star is completely destroyed,” he says. “But contrary to all other TDEs we know of, when we pointed our telescopes to the same location again several years later, we found that it had re-brightened again. This led us to propose that rather than being fatal, part of the star survived the initial encounter and returned to the same location to be stripped of material once more, explaining the re-brightening phase.”

[…]

So how could a star survive its brush with death? It all comes down to a matter of proximity and trajectory. If the star collided head-on with the black hole and passed the event horizon—the threshold where the speed needed to escape the black hole surpasses the speed of light—the star would be consumed by the black hole. If the star passed very close to the black hole and crossed the so-called “tidal radius”—where the tidal force of the hole is stronger than the gravitational force that keeps the star together—it would be destroyed. In the model they have proposed, the star’s orbit reaches a point of closest approach that is just outside of the tidal radius, but doesn’t cross it completely: some of the material at the stellar surface is stripped by the black hole, but the material at its center remains intact.

[…]

More information: T. Wevers et al, Live to Die Another Day: The Rebrightening of AT 2018fyk as a Repeating Partial Tidal Disruption Event, The Astrophysical Journal Letters (2023). DOI: 10.3847/2041-8213/ac9f36

Source: A team of physicists devise a model that maps a star’s surprising orbit about a supermassive black hole

You may not realize it in your day-to-day life, but we are all enveloped by a giant “superbubble” that was blown into space by the explosive deaths of a dozen-odd stars. Known as the Local Bubble, this structure extends for about 1,000 light years around the solar system, and is one of countless similar bubbles in our galaxy that are produced by the fallout of supernovas. Cosmic superbubbles have remained fairly mysterious for decades, but recent astronomical advances have finally exposed key details about their evolution and structure. Just within the past few years, researchers have mapped the geometry of the Local Bubble in three dimensions and demonstrated that its surface is an active site of star birth, because it captures gas and dust as it expands into space.

Now, a team of scientists has added another layer to our evolving picture of the Local Bubble by charting the magnetic field of the structure, which is thought to play a major role in star formation. Astronomers led by Theo O’Neill, who conducted the new research during a summer research program at the Center for Astrophysics at Harvard & Smithsonian (CfA), presented “the first-ever 3D map of a magnetic field over a superbubble” on Wednesday at the American Astronomical Society’s 241st annual meeting in Seattle, Washington. The team also unveiled detailed visualizations of their new map, bringing the Local Bubble into sharper focus.

“We think that the entire interstellar medium is really full of all these bubbles that are driven by various forms of feedback from, especially, really massive stars, where they’re outputting energy in some form or another into the space between the stars,” said O’Neill, who just received an undergraduate degree in astronomy-physics and statistics from the University of Virginia, in a joint call with their mentor Alyssa Goodman, an astronomer at CfA who co-authored the new research. […] “Now that we have this map, there’s a lot of cool science that can be done both by us, but hopefully by other people as well,” O’Neill said. “Since stars are clustered, it’s not as if the Sun is super special, and is in the Local Bubble because we’re just lucky. We know that the interstellar medium is full of bubbles like this, and there’s actually a lot of them nearby our own Local Bubble.” “One cool next step will be looking at places where the Local Bubble is nearby other feedback bubbles,” they concluded. “What happens when these bubbles interact, and how does that drive start formation in general, and the overall long-term evolution of galactic structures?”

Source: We Exist Inside a Giant Space Bubble, And Scientists Have Finally Mapped It – Slashdot

(Andromeda Galaxy)

In the quest to find the outer limits of our galaxy, astronomers have discovered over 200 stars that form the Milky Way’s edge, the most distant of which is over one million light-years away—nearly halfway to the Andromeda galaxy.

The 208 stars the researchers identified are known as RR Lyrae stars, which are stars with a brightness that can change as viewed from Earth. These stars are typically old and brighten and dim at regular intervals, which is a mechanism that allows scientists to calculate how far away they are. By calculating the distance to these RR Lyrae stars, the team found that the farthest of the bunch was located about halfway between the Milky Way and the Andromeda galaxy, one of our cosmic next-door neighbors.

“This study is redefining what constitutes the outer limits of our galaxy,” said Raja GuhaThakurta in a press release. GuhaThakurta is professor and chair of astronomy and astrophysics at the University of California Santa Cruz. “Our galaxy and Andromeda are both so big, there’s hardly any space between the two galaxies.”

The Milky Way galaxy consists of a few different parts, the primary of which is a thin, spiral disk about 100,000 light-years across. Our home solar system sits on one of the arms of this disk. An inner and outer halo surround the disk, and these halos contain some of the oldest stars in our galaxy.

Previous studies have placed the edge of the outer halo at 1 million light-years from the Milky Way’s center, but based on the new work, the edge of this halo should be about 1.04 million light-years from the galactic center. Yuting Feng, a doctoral student at the university working with GuhaThakurta, led the study and is presenting the findings this week at the American Astronomical Society meeting in Seattle.

[…]

Source: Astronomers Find the Edge of Our Galaxy

While using the Atacama Large Millimeter/submillimeter Array (ALMA) to study the masers around oddball star MWC 349A scientists discovered something unexpected: a previously unseen jet of material launching from the star’s gas disk at impossibly high speeds. What’s more, they believe the jet is caused by strong magnetic forces surrounding the star.

The discovery could help researchers to understand the nature and evolution of massive stars and how hydrogen masers are formed in space. The new observations were presented today (January 9) in a press conference at the 241st meeting of the American Astronomical Society (AAS) in Seattle, Washington.

Located roughly 3,900 light-years away from Earth in the constellation Cygnus, MWC 349A’s unique features make it a hot spot for scientific research in optical, infrared, and radio wavelengths. The massive star—roughly 30 times the mass of the sun—is one of the brightest radio sources in the sky, and one of only a handful of objects known to have hydrogen masers. These masers amplify microwave radio emissions, making it easier to study processes that are typically too small to see. It is this unique feature that allowed scientists to map MWC 349A’s disk in detail for the first time.

“A maser is like a naturally occurring laser,” said Sirina Prasad, an undergraduate research assistant at the Center for Astrophysics | Harvard & Smithsonian (CfA), and the primary author of the paper. “It’s an area in outer space that emits a really bright kind of light. We can see this light and trace it back to where it came from, bringing us one step closer to figuring out what’s really going on.”

Leveraging the resolving power of ALMA’s Band 6, developed by the U.S. National Science Foundation’s National Radio Astronomy Observatory (NRAO), the team was able to use the masers to uncover the previously unseen structures in the star’s immediate environment. Qizhou Zhang, a senior astrophysicist at CfA, and the project’s principal investigator added, “We used masers generated by hydrogen to probe the physical and dynamic structures in the gas surrounding MWC 349A and revealed a flattened gas disk with a diameter of 50 au, approximately the size of the Solar System, confirming the near-horizontal disk structure of the star. We also found a fast-moving jet component hidden within the winds flowing away from the star.”

The observed jet is ejecting material away from the star at a blistering 500 km per second. That’s akin to traveling the distance between San Diego, California, and Phoenix, Arizona, in the literal blink of an eye. According to researchers, it is probable that a jet moving this fast is being launched by a magnetic force. In the case of MWC 349A, that force could be a magnetohydrodynamic wind—a type of wind whose movement is dictated by the interplay between the star’s magnetic field and gases present in its surrounding disk.

“Our previous understanding of MWC 349A was that the star was surrounded by a rotating disk and photo-evaporating wind. Strong evidence for an additional collimated jet had not yet been seen in this system. Although we don’t yet know for certain where it comes from or how it is made, it could be that a magnetohydrodynamic wind is producing the jet, in which case the magnetic field is responsible for launching rotating material from the system,” said Prasad. “This could help us to better understand the disk-wind dynamics of MWC 349A, and the interplay between circumstellar disks, winds, and jets in other star systems.”

More information: These results will be presented during a press conference at the 241st proceedings of the American Astronomical Society on Monday, January 9th at 2:15pm Pacific Standard Time (PST).

Source: Hydrogen masers reveal new secrets of a massive star

[…]

It’s not only star gazing that’s in jeopardy. Culture, wildlife and other scientific advancements are being threatened by mass light infrastructure that is costing cities billions of dollars a year as it expands alongside exponential population growth.

Some researchers call light pollution cultural genocide. Generations of complex knowledge systems, built by Indigenous Australians and Torres Strait Islanders upon a once-clear view of the Milky Way, are being lost.

In the natural world, the mountain pygmy possum, a marsupial native to Australia, is critically endangered. Its main food source, the bogong moth, is being affected by artificial outdoor lighting messing with its migration patterns. Sea turtles are exhibiting erratic nesting and migration behaviours due to lights blasting from new coastal developments.

So how bright does our future look under a blanket of light?

“If you go to Mount Coot-tha, basically the highest point in Brisbane, every streetlight you can see from up there is a waste of energy,” Downs says. “Why is light going up and being wasted into the atmosphere? There’s no need for it.”

Skyglow

Around the world, one in three people can’t see the Milky Way at night because their skies are excessively illuminated. Four in five people live in towns and cities that emit enough light to limit their view of the stars. In Europe, that figure soars to 99%.

Blame skyglow – the unnecessary illumination of the sky above, and surrounding, an urban area. It’s easy to see it if you travel an hour from a city, turn around, then look back towards its centre.

[…]

Artificial lights at night cause skyglow in two ways: spill and glare. Light spills from a bulb when it trespasses beyond the area intended to be lit, while glare is a visual sensation caused by excessive brightness.

Streetlights contribute hugely to this skyglow and have been causing astronomers anxiety for decades.

[…]

Source: Blinded by the light: how skyglow pollution is separating us from the stars | Queensland | The Guardian

For years, scientific researchers have warned that Elon Musk’s Starlink low Earth orbit (LEO) satellite broadband constellations are harming scientific research. Simply put, the light pollution Musk claimed would never happen in the first place is making it far more difficult to study the night sky, a problem researchers say can be mitigated somewhat but never fully eliminated.

Musk and company claim they’re working on upgraded satellites that are less obtrusive to scientists, but it’s Musk, so who knows if those solutions actually materialize. Musk isn’t alone in his low-orbit satellite ambitions. Numerous other companies, including Jeff Bezos’ Blue Origin, are planning to fling tens of thousands of these low-orbit satellite “megaconstallations” into the heavens.

One 2020 paper argued that the approval of these low-orbit satellites by the FCC technically violated the environmental law embedded in the 1970 U.S. National Environmental Policy Act (NEPA). Scientific American notes how the FCC has thus far sidestepped NEPA’s oversight, thanks to a “categorical exclusion” the agency was granted in 1986 — long before LEO satellites were a threat.

Last week yet another study emerged from the U.S. Government Accountability Office (GAO, full study here), recommending that the FCC at least revisit the issue:

“We think they need to revisit [the categorical exclusion] because the situation is so different than it was in 1986,” says Andrew Von Ah, a director at the GAO and one of the report’s two lead authors. The White House Council on Environmental Quality (CEQ) recommends that agencies “revisit things like categorical exclusions once every seven years,” Von Ah says. But the FCC “hasn’t really done that since 1986.”

Despite the fact that low-earth orbit solutions like Starlink generally lack the capacity to be meaningfully disruptive to the country’s broadband monopolies, and are, so far, too expensive to address one of the biggest obstacles to adoption (high prices due to said monopolies), the FCC has generally adopted a “we’re too bedazzled by the innovation to bother” mindset until recently.

The FCC this year did recently decide to roll back nearly a billion in Trump-era subsidies for Starlink (in part because the company misled regulators about coverage, but also because the FCC doubted they’d be able to deliver promised speeds and coverage). And the FCC did recently enact laws tightening up requirements for discarding older, failed satellites to address “space junk.”

But taking a tougher stand here would require the FCC taking a bold stance on whether or not NEPA actually applies to the “environment” of outer space and low-Earth orbit, which remains in debate. This is an agency that can’t even be bothered to publicly declare with any confidence that telecom monopolies exist or are a problem, so it seems pretty unlikely they’d want to wade into such controversy.

Like a lot of Musk efforts (like the fatal public potential of misrepresented “full self driving” technology), the issue has been simplistically framed as one of innovation versus mean old pointless government bureaucracy. This simplistic distortion has resulted in zero meaningful oversight as problems mount, something that impacts not just the U.S. (where most launches occur), but every nation on the planet:

“Our society needs space,” says Didier Queloz, an astronomer and Nobel laureate at the University of Cambridge. “I have no problem with space being used for commercial purposes. I just have a problem that it’s out of control. When we started to see this increase in satellites, I was shocked that there are no regulations. So I was extremely pleased to hear that there has been an awareness that it cannot continue like that.”

I’d expect this issue gets punted into the bowels of agency policy purgatory. Even if the agency does act it will be years from now, and unlikely to apply to the satellite licenses already doled out to companies like Starlink and Amazon. And while there are several bills aimed at tightening up restrictions in the space, it seems unlikely any of them are going to survive a dysfunctional and corrupt Congress.

That means that the light pollution caused by LEO satellites will continue to harm scientific researchers, who’ve been forced to embrace expensive, temporary solutions to the problem that are very unlikely to scale effectively as even more LEO companies set their sights on the heavens.

Source: Debate Continues Over What To Do About The Fact That Starlink, Other Low-Earth-Orbit Satellite Systems Are Causing Irreversible, Research-Harming Light Pollution | Techdirt

Beams of electrons smash into slower-moving particles causing a shock wave which results in electromagnetic radiation across frequency bands from X-rays to visible light, according to a research paper published in Nature this week.

Astronomers first observed quasi-stellar radio sources or quasars in the early 1960s. This new class of astronomical objects was a puzzle. They looked like stars, but they also radiated very brightly at radio frequencies, and their optical spectra contained strange emission lines not associated with “normal” stars. In fact, these strange objects are gigantic black holes at the center of distant galaxies.

Particle acceleration in the jet emitted by a supermassive black hole. Illustration credit: Liodakis et al/Nature

Advances in radio-astronomy and X-ray-observing satellites have helped scientists understand that the anomalous radiation is caused by a stream of charged particles accelerated close to the speed of light. If it points at Earth, the generating quasar can be called a blazar. Electromagnetic radiation from them can be observed from radio waves through the visible spectrum to very high-frequency gamma rays.

[…]

By comparing polarized X-rays data with data about optical polarized visible light, the scientists reached the conclusion that the electromagnetic radiation resulted from a shock wave in the stream of charged particles emitting from the blackhole (see figure).

In an accompanying article, Lea Marcotulli, NASA Einstein Postdoctoral Fellow at Yale University, said: “Such shock waves occur naturally when particles travelling close to the speed of light encounter slower-moving material along their path. Particles traveling through this shock wave lose radiation rapidly and efficiently – and, in doing so, they produce polarized X-rays. As the particles move away from the shock, the light they emit radiates with progressively lower frequencies, and becomes less polarized.”

[…]

In December last year, a SpaceX Falcon 9 rocket launched NASA’s IXPE mission into orbit from Florida’s Kennedy Space Center. It is designed to observe the remnants of supernovae, supermassive black holes, and other high-energy objects.

[…]

Source: Bright light from black holes caused by particle shock waves • The Register

A team of researchers with members from Universidad Nacional de San Juan, Universidade Federal do Rio Grande do Sul and Universidad Andres Bello has found evidence of a large extragalactic assembly hiding behind one part of the Milky Way galaxy. The group has published a paper describing their findings on the arXiv preprint server while awaiting publication in the journal Astronomy & Astrophysics.

Space scientists have known for some time that there is one part of the night sky that is mostly obscured from view due to a bulge in the galaxy. Known as the “zone of avoidance,” it makes up approximately 10% of the dark sky and has had researchers wondering what might be behind it

[…]

In studying the infrared imagery, the researchers found that they were able to identify several galaxies that exist far beyond the Milky Way. And because of their numbers, the researchers believe that together, they make up what they describe as a massive extragalactic structure. They estimate that there might be as many as 58 galaxies in the structure.

More information: Daniela Galdeano et al, Unveiling a new structure behind the Milky Way, arXiv (2022). DOI: 10.48550/arxiv.2210.16332

Source: Huge extragalactic structure found hiding behind the Milky Way

last December when the lander detected a massive quake on Mars.

Now, scientists know what caused the red planet to rumble. A meteoroid slammed into Mars 2,174 miles (3,500 kilometers) away from the lander and created a fresh impact crater on the Martian surface.

The ground literally moved beneath InSight on December 24, 2021, when the lander recorded a magnitude 4 marsquake. Before and after photos captured from above by the Mars Reconnaissance Orbiter, which has been circling Mars since 2006, spotted a new crater this past February.

Before and after photos taken by the Mars Reconnaissance Orbiter show where a meteoroid slammed into Mars on December 24, 2021.

NASA/JPL-Caltech/MSSS

When scientists connected the dots from both missions, they realized it was one of the largest meteoroid strikes on Mars since NASA began studying the red planet. Images from the orbiter’s two cameras showed the blast zone of the crater, which allowed scientists to compare it with the epicenter of the quake detected by InSight.

The journal Science published two new studies describing the impact and its effects on Thursday.

The space rock also revealed boulder-size ice chunks when it slammed into Mars. They were found buried closer to the warm Martian equator than any ice that has ever been detected on the planet.

Boulder-size ice chunks can be seen scattered around and outside the new crater’s rim.

NASA/JPL-Caltech/University of Arizona

“The image of the impact was unlike any I had seen before, with the massive crater, the exposed ice, and the dramatic blast zone preserved in the Martian dust,” said Liliya Posiolova, orbital science operations lead for the orbiter at Malin Space Science Systems in San Diego, in a statement.

[…]

When the meteoroid crashed into Mars, it created a crater in the planet’s Amazonis Planitia region spanning 492 feet (150 meters) across and 70 feet (21 meters) deep. Some of the material blasted out of the crater landed as far as 23 miles (37 kilometers) away. Teams at NASA also captured sound from the impact, so you can listen to what it sounds like when a space rock hits Mars.

The images captured by the orbiter, along with seismic data recorded by InSight, make the impact one of the largest craters in our solar system ever observed as it was created. Mars is littered with massive craters, but they’re much older than any mission to explore the red planet.

[…]

Ice beneath the Martian surface could be used for drinking water, rocket propellant and even growing crops and plants by future astronauts. And the fact that the ice was found so near the equator, the warmest region on Mars, might make it an ideal place to land crewed missions to the red planet.

[…]

Sadly, InSight’s mission is running out of time. Increasing amounts of dust have settled on the lander’s solar panels, only exacerbated by a continent-size dust storm detected on Mars in September, and its power levels keep dropping.

The beige clouds are a continent-size dust storm imaged by the Mars Reconnaissance Orbiter on September 29. The locations of the Perseverance, Curiosity and InSight missions are also labeled.

NASA/JPL-Caltech/MSSS

Fortunately, the storm didn’t pass over InSight directly — otherwise, the darkness of the storm would have ended the mission. But the weather event has kicked a lot of dust up into the atmosphere, and it has cut down the amount of sunlight reaching InSight’s solar panels, said Bruce Banerdt, InSight principal investigator at NASA’s Jet Propulsion Laboratory in Pasadena, California.

InSight lander’s final selfie on Mars shows why its mission is ending

The mission scientists estimate InSight will likely shut down in the next six weeks, ending a promising mission to unlock the interior of Mars.

[…]

Source: Space rock slams into Mars and reveals buried ice | CNN

NASA’s Lucy spacecraft captured this image (which has been cropped) of the Earth on Oct 15, 2022, as a part of an instrument calibration sequence at a distance of 380,000 miles (620,000 km). The upper left of the image includes a view of Hadar, Ethiopia, home to the 3.2 million-year-old human ancestor fossil for which the spacecraft was named.

Lucy is the first mission to explore the Jupiter Trojan asteroids, an ancient population of asteroid “fossils” that orbit around the Sun at the same distance as Jupiter. To reach these distant asteroids, the Lucy spacecraft’s trajectory includes three Earth gravity assists to boost it on its journey to these enigmatic asteroids.

The image was taken with Lucy’s Terminal Tracking Camera (T2CAM) system, a pair of identical cameras that are responsible for tracking the asteroids during Lucy’s high-speed encounters. The T2CAM system was designed, built and tested by Malin Space Science Systems; Lockheed Martin Integrated the T2CAMs onto the Lucy spacecraft and operates them.

Credits: NASA/Goddard/SwRI

On October 13, 2022, NASA’s Lucy spacecraft captured this image of the Earth and the Moon from a distance of 890,000 miles (1.4 million km). The image was taken as part of an instrument calibration sequence as the spacecraft approached Earth for its first of three Earth gravity assists. These Earth flybys provide Lucy with the speed required to reach the Trojan asteroids — small bodies that orbit the Sun at the same distance as Jupiter. On its 12 year journey, Lucy will fly by a record breaking number of asteroids and survey their diversity, looking for clues to better understand the formation of the solar system.

The image was taken with Lucy’s Terminal Tracking Camera (T2CAM) system, a pair of identical cameras that are responsible for tracking the asteroids during Lucy’s high speed encounters. The T2CAM system was designed, built and tested by Malin Space Science Systems; Lockheed Martin Integrated the T2CAMs onto the Lucy spacecraft and operates them.

Source: NASA’s Lucy Spacecraft Captures Images of Earth, Moon Ahead of Gravity | NASA

A new aerospace company reached orbit with its second rocket launch and deployed multiple small satellites on Saturday.

Firefly Aerospace’s Alpha rocket lifted off from Vandenberg Space Force Base, California, in early morning darkness and arced over the Pacific.

“100% mission success,” Firefly tweeted later.

A day earlier, an attempt to launch abruptly ended when the countdown reached zero. The first-stage engines ignited but the rocket automatically aborted the liftoff.

The rocket’s payload included multiple small satellites designed for a variety of technology experiments and demonstrations, as well as educational purposes.

The mission, dubbed “To The Black,” was the company’s second demonstration flight of its entry into the market for small satellite launchers.

The first Alpha was launched from Vandenberg on Sept. 2, 2021, but did not reach orbit.

One of the four first-stage engines shut down prematurely but the rocket continued upward on three engines into the supersonic realm where it tumbled out of control.

The rocket was then intentionally destroyed by an explosive flight termination system.

Firefly Aerospace said the premature shutdown was traced to an electrical issue, but that the rocket had otherwise performed well and useful data was obtained during the nearly 2 1/2 minutes of flight.

Alpha is designed to carry payloads weighing as much as 2,579 pounds (1,170 kilograms) to low Earth orbit.

Other competitors in the burgeoning small-launch market include Rocket Lab and Virgin Orbit, both headquartered in Long Beach, California.

Firefly Aerospace, based in Cedar Park, Texas, is also planning a larger rocket, a vehicle for in-space operations and a lander for carrying NASA and commercial payloads to the surface of the moon.

Source: Firefly Aerospace reaches orbit with new Alpha rocket

The US Federal Communications Commission (FCC) has adopted new rules to address the growing risk of “space junk” or abandoned satellites, rockets and other debris. The new “5-year-rule” will require low-Earth operators to deorbit their satellites within five years following the completion of missions. That’s significantly less time than the previous guideline of 25 years.

“But 25 years is a long time,” FCC Chairwoman Jessica Rosenworcel said in a statement. “There is no reason to wait that long anymore, especially in low-earth orbit. The second space age is here. For it to continue to grow, we need to do more to clean up after ourselves so space innovation can continue to respond.”

Rosenworcel noted that around 10,000 satellites weighing “thousands of metric tons” have been launched since 1957, with over half of those now defunct. The new rule “will mean more accountability and less risk of collisions that increase orbital debris and the likelihood of space communication failures.”

[…]

Source: Satellites must be deorbited within five years of completing missions, FCC rules | Engadget

Why 5 years? it’s still too long!

Does the existence of life on Earth tell us anything about the probability of abiogenesis—the origin of life from inorganic substances—arising elsewhere? That’s a question that has confounded scientists, and anyone else inclined to ponder it, for some time.

A widely accepted argument from Australian-born astrophysicist Brandon Carter argues that the selection effect of our own existence puts constraints on our observation. Since we had to find ourselves on a planet where abiogenesis occurred, then nothing can be inferred about the probability of life elsewhere based on this knowledge alone.

At best, he argued, the knowledge of life on Earth is of neutral value. Another way of looking at it is that Earth can’t be considered a typical Earth-like planet because it hasn’t been selected at random from the set of all Earth-like planets.

However, a new paper by Daniel Whitmire, a retired astrophysicist who currently teaches mathematics at the U of A, is arguing that Carter used faulty logic. Though Carter’s theory has become widely accepted, Whitmire argues that it suffers from what’s known as “the old evidence problem” in Bayesian confirmation theory, which is used to update a theory or hypothesis in light of new evidence.

After giving a few examples of how this formula is employed to calculate probabilities and what role old evidence plays, Whitmire turns to what he calls the conception analogy.

As he explains, “One could argue, like Carter, that I exist regardless of whether my conception was hard or easy, and so nothing can be inferred about whether my conception was hard or easy from my existence alone.”

In this analogy, “hard” means contraception was used. “Easy” means no contraception was used. In each case, Whitmire assigns values to these propositions.

Whitmire continues, “However, my existence is old evidence and must be treated as such. When this is done the conclusion is that it is much more probable that my conception was easy. In the abiogenesis case of interest, it’s the same thing. The existence of life on Earth is old evidence and just like in the conception analogy the probability that abiogenesis is easy is much more probable.”

In other words, the evidence of life on Earth is not of neutral value in making the case for life on similar planets. As such, our life suggests that life is more likely to emerge on other Earth-like planets—maybe even on the recent “super-Earth” type planet, LP 890-9b, discovered 100 light years away.

Those with a taste for math can read Whitmire’s paper, “Abiogensis: The Carter Argument Reconsidered,” in the International Journal of Astrobiology.

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Explore further

The implications of cosmic silence

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More information: Daniel P. Whitmire, Abiogenesis: the Carter argument reconsidered, International Journal of Astrobiology (2022). DOI: 10.1017/S1473550422000350

Source: New theory concludes that the origin of life on Earth-like planets is likely

Voyager and Lockheed Martin have found a partner to design astronaut facilities for their space station. Hilton will develop suites and sleeping quarters for Starlab, CNBC reports. Under the partnership, Hilton and Voyager will also look at marketing opportunities related to Starlab and trips to what may be one of the first space hotels.

NASA has granted contracts to four private companies who are building private space stations ahead of the agency’s planned decommissioning of the International Space Station at the end of the decade. Axiom Space, Blue Origin and Northrop Grumman are also working on space stations. Voyager’s operating company Nanoracks received the largest contract, which was valued at $160 million.

Voyager and Lockheed Martin hope to have the first Starlab up and running by 2027.

Source: Hilton will design suites and sleeping quarters for Voyager’s private Starlab space station | Engadget

Space is getting a little too crowded, increasing the risk of orbital collisions. Slingshot Aerospace, a company specializing in space data analytics, is now offering a solution to regulate some of the traffic up there. The company announced on Tuesday that it is rolling out a free version of its space traffic control system to help satellite operators dodge collisions.

[…]

The company’s Slingshot Beacon software works like an air traffic control system, but for spacecraft in orbit. It pulls in public and private data provided by Slingshot’s customers to create a space catalog. The system then sends out urgent collision alerts to satellite operators worldwide, coordinates satellite maneuvers should there be a risk of collision, and allows operators to communicate with each other, especially during high-risk moments.

Slingshot Aerospace launched Beacon a year ago and is now offering a free basic version to satellite operators in hopes of increasing the number of users on its platform. “We’ve been testing it for the past year with a select few so as not to get overwhelmed by the data,” Stricklan said. “And we have 100% confidence that we are ready to scale to a global scale.” By offering the free version, the company anticipates that some satellite operators will seek the software’s advanced options, which offer more accurate and refined data.

There are more than 9,800 satellites in orbit today, with more than 115,000 planned to launch by 2030, according to Slingshot’s space object database. And that’s in addition to the thousands of pieces of space junk currently in orbit around our planet. Some satellite operators are currently working with outdated technology that wasn’t designed for the volume of spacecraft in orbit today, making then unreliable when it comes to issuing warnings of potential in-space collisions. “There’s a lot of noise out there,” Stricklan said. “They’re getting thousands of [collision warnings] a day, so it just turns into noise.”

[…]

Source: This Startup’s Free Software Could Prevent Satellite Collisions

Astronomers have found a baby planet hidden in clouds of gas and dust swirling within a young solar system, by studying the accumulation of material around Lagrange points.

That’s according to research published this week in The Astrophysical Journal Letters.

Studying these protoplanets is difficult. Their stellar nurseries are shrouded in thick, hot clumps of mostly hydrogen gas, preventing astronomers from clearly observing the birth of stars and planets.

“Directly detecting young planets is very challenging and has so far only been successful in one or two cases,” Feng Long, first author of the study and a postdoctoral fellow at the Center for Astrophysics at Harvard, said. “The planets are always too faint for us to see because they’re embedded in thick layers of gas and dust.”

To overcome this hurdle, Long and her colleagues developed a method to detect baby worlds, and used it to discover what appears to be a young planet forming around LkCa 15, a juvenile star located 518 light-years from Earth.

Here’s how the team said they did it. They used observational data gathered from the ALMA telescope, which revealed a clump of mass and an arc-shaped feature, both telltale signs that something else is forming within the dense protoplanetary disk of matter surrounding the young star.

These images did not, however, provide hard evidence of a planet forming around that sun. But another measurement connecting the pair of features convinced the team they had found an alien world in the making. “This arc and clump are separated by about 120 degrees,” Long said. “That degree of separation doesn’t just happen — it’s important mathematically.”

The separation showed these two features lie at Lagrange points, points in space around which objects can orbit stably thanks to the gravitational pull of two nearby large objects – for example, a star and a planet

[…]

The data from LkCa 15 showed the arc is located at the L4 point and the clump is at L5. These are so placed because another object – a hidden planet – is orbiting between them; the Lagrange points are the result of the gravitational pull by the young star and its forming world, just as the Sun and Earth form Lagrange points

[…]

Long and her colleagues used the data to simulate the growth of a planet with similar properties to the one they thought they had found, and compared their model’s results with the telescope’s images.

Strong similarities between the simulations and observational data showed a planet is likely forming around LkCa 15. The mystery object is estimated to be about the size of Neptune or Saturn, and orbits around the star at quite a distance – 42 times the distance between the Sun and Earth

[…]

“[We] put a planet into a disk full of gas parcels and dust particles, and see how they interact and evolve under known physics,” […] This model image will show what the millimeter wavelength emission would look like, [so we can] make a direct comparison with our observations.”

[…]

Source: Astronomers describe how they found a baby planet forming • The Register