Friday, February 02, 2024

SPACE

Newborn planets look more like Smarties than spheres, study suggests


Nilima Marshall, PA Science Reporter
Fri, 2 February 2024 

When new planets form around stars they have flattened shapes, like Smarties, and are not spherical as previously thought, scientists have said.

Researchers at the University of Central Lancashire (UCLan) used computer simulations to model the formation of planets.

To develop their models, the team used a concept in astrophysics known as the theory of disk instability – where planets form in short timescales from the breaking up of large rotating discs of dense gas and dust orbiting young stars.


The researchers said it is the first time scientists have looked at the shape of newborn planets in simulations as they form.

Dr Dimitris Stamatellos, reader in astrophysics at UCLan, said these young planets are oblate spheroids – spheres squashed from the top and the bottom but bulging in the middle.

A simulated young planet as viewed from the top and from the side (Adam Fenton/Dimitris Stamatellos/University of Central Lancashire/PA)

He said: “We have been studying planet formation for a long time but never before had we thought to check the shape of the planets as they form in the simulations.

“We had always assumed that they were spherical.

“We were very surprised that they turned out to be oblate spheroids, pretty similar to Smarties!”

Technically, no planet is fully spherical.

Dr Stamatellos said Jupiter’s flattening, for example, is around 6%, while Saturn is 10%, and Earth is almost spherical at just 0.3%.

He said that young planets on the other hand are much flatter, somewhere around 90%.

For their study, published in the journal Astronomy & Astrophysics Letters, the team investigated the shapes of young planets and how they grow to become gas giants like Jupiter.

The scientists also discovered that new planets grow as material falls on to them, mainly from their poles rather than their equators.

They said the findings have important implications, particularly when viewing planets through a telescope as their shapes will vary depending on the viewing angle.

The researchers said observational confirmation of the Smarties-like shape of young planets could also help answer a key question about how they form.

There are two theories on planet formation. The first and most widely accepted one is the core accretion model, where dust particles gradually grow and stick together to form large planets in long timescales.

But while this works well to explain the formation of planets such as Earth it does not fully account for gas giants – ones much larger than Jupiter – as the process would take too long.

The second theory – which is disk instability – is less favoured but may account for the creation of larger planets at rapid timescales.

The researchers said their work points towards the disc instability model rather than the core accretion one.

Dr Adam Fenton, a recently graduated PhD student at UCLan’s Jeremiah Horrocks Institute for Mathematics, Physics and Astronomy, who led the research, said: “Many exoplanets, which are planets that orbit stars in other solar systems outside of our own, have been discovered in the last three decades.

“Despite observing many thousands of them, how they form remains unexplained.

“It is believed that they either form through core accretion, which is a gradual growth of dust particles that stick together to form progressively larger and larger objects on long timescales, or directly by the breaking up of large rotating protostellar discs around young stars in short timescales, which is what we call the theory of disk instability.

“This theory is appealing due to the fact that large planets can form very quickly at large distances from their host star, explaining some exoplanet observations.”


X-ray image of universe reveals almost 1 million high-energy objects: 'These are mind-blowing numbers'

Robert Lea
Thu, February 1, 2024 

Two versions of the eROSITA All-Sky Survey Catalogue (eRASS1) data (Right) the X-ray sky over earth (right) X-ray sources.


The first data released to the public from the eROSITA sky survey comprises an X-ray view of half the sky over Earth, encompassing almost a million high-energy cosmic sources, including over 700,000 supermassive black holes.

This catalog, dubbed the "eROSITA All-Sky Survey Catalogue (eRASS1)" was published on Thursday (Feb. 1). It constitutes the largest-ever catalog of the universe's most powerful sources of energy, like exploding massive stars and black hole-powered active galactic nuclei that shine brightly in X-rays. The release also details the largest known structures in the universe — cosmic web filaments of hot gas that connect galaxies in clusters.

The results show that, in just half a year of operations beginning after launch on July 13, 2019, eROSITA has managed to discover more high-energy X-ray sources than has been found in six decades of examining the sky.

Considered a major milestone in the 60 or so years of X-ray astronomy, eRASS1 could help answer some of cosmology's biggest questions: How did the universe evolve, and why is the very fabric of space expanding at an accelerating rate?

Related: Mysterious dark energy is spread evenly across the cosmos

Accompanying the eRASS1 data are almost 50 scientific papers published across a range of topics, adding to an existing 200 papers already written using data from the eROSITA telescope.

The main aim of eROSITA is to use clusters of galaxies to observe how dark energy accelerates the expansion of the universe; these 250 or so papers, however, demonstrate the extent to which the instrument and its data have gone beyond this goal.

These papers include the discovery of over 1,000 superclusters of galaxies, the revelation of two quasi-periodic erupting black holes, and the determination of the impact that stars' X-ray radiation has on water and atmosphere retention of planets that orbit them.

"The scientific breadth and impact of the survey is quite overwhelming; it's hard to put into a few words," spokesperson for the German eROSITA consortium, Mara Salvato, said in a statement. "But the papers published by the team will speak for themselves."
eROSITA lets the numbers do the talking

The eRASS1 data consists of eROSITA telescope observations conducted from Dec. 12, 2019, to June 11, 2020. from across half the sky over Earth. During this period, the space telescope detected around 170 million individual particles of X-ray light or "photons."

Processing these photons revealed 900,000 X-ray sources, of which 700,000 are feeding supermassive black holes that power quasars at the hearts of active galactic nuclei, regions in the centers of galaxies so bright they can outshine the combined light of every star in those galaxies themselves.

Also seen in the eRASS1 are 180,000 X-ray-emitting stars in the Milky Way, 12,000 clusters of galaxies and even exotic classes of X-ray sources like binary stars, supernova remnantspulsars and other such objects.

"These are mind-blowing numbers for X-ray astronomy," Andrea Merloni, eROSITA principal investigator and first author of the eROSITA catalog paper, said in a statement. "We've detected more sources in 6 months than the big flagship missions XMM-Newton and Chandra have done in nearly 25 years of operation."

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The data release is also impressive in terms of the spread of its observations, with the sky over Earth imaged at multiple X-ray energies. In addition to this, eROSITA is incredibly precise, with its first data release also pinpointing positions in the sky from which individual photons are received, as well as these photons' arrival times and energies.

Along with the release, the eROSITA Consortium has also made available the software needed to analyze data from the X-ray telescope as well as catalogs that go beyond just X-ray data.

"We've made a huge effort to release high-quality data and software," eROSITA Operations team leader, Iriam Ramos-Ceja, said. "We hope this will broaden the base of scientists worldwide working with high-energy data and help push the frontiers of X-ray astronomy."


China puts models of its future crewed moon landing spacecraft on display (video)

Andrew Jones
Thu, February 1, 2024 

An illustration of a Chinese moon base.


China is displaying models of the rockets and spacecraft it is developing to send its astronauts to the moon.

The event, the "Exhibition of Achievements in China Manned Space Program," opened in Shanghai at the New International Expo Center on Dec. 29.

The exhibition features the Long March 10 rocket, a lunar lander spacecraft and a next-generation crew spacecraft.

Related: Not just Artemis: China and Russia plan to put boots on the moon, too

astronauts walk on the surface of the moon among

The Long March 10 builds on China's current rocket, the Long March 5. The next-gen spacecraft inherits technology from the current Shenzhou spacecraft that sends astronauts to China's Tiangong space station. China has already conducted three successful robotic lunar landings with the Chang'e 3, 4 and 5 missions.

China's moon landing plan is to launch two Long March 10 rockets, with one for the lander and another for the crew spacecraft. The lander and the crewed spacecraft will rendezvous and dock in lunar orbit. A pair of astronauts will then move over to the lander and then head down to the lunar surface, where they will do a variety of scientific work and collect some moon samples during a stay lasting around six hours.

"The development of the lunar lander and the new spacecraft is still taking advantage of the previous technologies. We are also accelerating the assessment and development of the manned lunar rover," Fan Ping, chief designer of space stations at Shanghai Academy of Spaceflight Technology (SAST), told China Central Television.

RELATED STORIES:

— Here's what China's 1st moon landing with astronauts might look like (video)

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"China has announced the goal of landing people on the moon by 2030," Fan Ping said. "And after the goal is accomplished, the next could be the building of a lunar research station, so that we can establish our own home on the moon for more scientific experiments."

China is currently working on attracting partners for a project called the International Lunar Research Station. The country, together with Russia and other partners, aims to begin building the lunar outpost after launching precursor Chang'e 7 and 8 missions around 2026 and 2028.

A Mars Rover Discovered Bizarre Underground Polygons. What Could They Mean?

Darren Orf
Wed, January 31, 2024 

Rover Reveals Bizarre Shapes on Martian Surface
China National Space Agency

For one Earth year, the Chinese rover Zhurong explored beneath the surface of Mars using its ground-penetrating radar.


A new study has shown that the rover uncovered polygonal wedges 35 kilometers underground—the first ever found below the planet’s surface.


Evidence suggests that the wedges formed 3.7 to 2.9 billion years ago due to serious climatic changes in Mars’ past.


On May 14, 2021, China became the second country to ever deploy a rover on the Martian surface. Named Zhurong after the ancient Chinese god of fire, the rover landed on Mars’ Utopia Planitia—the largest impact basin on Mars (and the entire Solar System for that matter).

Equipped with a ground-penetrating radar system, Zhurong quickly got to work and far outlasted its originally planned three-month mission—it eventually shut down in May 2022 after a little more than an Earth year on Mars. In that time, the rover gathered invaluable data about what’s going on beneath the Martian surface, including surprising polygonal shapes located 35 meters below.

This previously unknown geologic structure—along with what it says about Mars’ past—was detailed in a recent study, published in the journal Nature Astronomy, written by scientists at the Institute of Geology and Geophysics under the Chinese Academy of Sciences.

“The … formation mechanism for the buried palaeo-polygonal terrain requires a cold environment and might be related to water/ice freeze–thaw processes in southern Utopia Planitia on early Mars,” the paper reads. “The detected buried polygons, which indicate that freezing occurred at low-to-mid latitudes, require strong palaeoclimatic variability.”


A detailed process of how these Martian polygonal wedges formed over billions of years. Zhang et al.

While never before discovered underneath the surface, these polygonal structures on Mars aren’t exactly a new discovery, as Universe Today explains. For example, NASA spotted them on the surface of the red planets’ northern lowlands back in 2012, saying at the time that “scientists study polygonally-patterned ground on Mars because the occurrence and physical characteristics of the polygons helps us understand the recent and past distribution of ice in the shallow subsurface [and] also provide clues about climate conditions.”

Similarly interested in what “clues” these shapes could uncover, scientists used Zhurong’s data to detect 16 polygonal wedges within 1.2 kilometers. They estimate that these shapes formed during the Late Hesperian—Early Amazonian epochs (yes, Mars has epochs, too), which occurred roughly 3.7 to 2.9 billion years ago. These wedges formed “possibly with the cessation of an ancient wet environment,” according to the paper.

One thing the researchers are certain about is that such a formation would require cold temperatures. “The possible presence of water and ice required for the freeze–thaw process in the wedges may have come from cryogenic suction-induced moisture migration from an underground aquifer on Mars, snowfall from the air or vapor diffusion for pore ice deposition,” the paper says.

While today’s Mars seems like a uniform, desert-like planet, evidence of dynamic history can still be found etched on its surface—and many meters beneath.


Photos Show Catastrophic Damage to Mars Helicopter

Victor Tangermann
Wed, January 31, 2024 


Rotor Damage

Last week, NASA announced that its historic Ingenuity helicopter, which had taken flight on Mars an incredible 72 times since its maiden voyage in April 2021, had died.

The agency's Jet Propulsion Lab shared pictures following the rotorcraft's final flight, showing some gnarly damage — via the shadow its shattered rotor casts on the unearthly landscape.


One picture even appears to show a small piece of the rotor lying on the dusty ground nearby.


You can also see the damage in a series of image strung together into a video:

https://twitter.com/landru79/status/1751976365237117224

"While the helicopter remains upright and in communication with ground controllers, imagery of its January 18 flight sent to Earth this week indicates one or more of its rotor blades sustained damage during landing and it is no longer capable of flight," NASA wrote in its statement.

It's an unfortunate end to a groundbreaking mission, which proved once and for all that we're capable of taking flight on a distant planet.
Coaxial Copter

It's a technological marvel that the four-pound helicopter lasted as long as it did. Its rotor blades were made of carbon fiber and arranged into two four-foot-long, counter-rotating rotors, which could spin up to around 2,400 revolutions per minute.

Thanks to the thin Martian atmosphere, the rotors had to spin roughly ten times as fast as they would have needed to back on Earth.

Scientists carefully fine-tuned the blades over years of testing, adjusting their weight and size while accommodating the extreme temperature swings and wind gusts on the Martian surface.

And given Ingenuity's incredible track record, their hard work clearly paid off. Originally intended as a technology demonstration, the rotorcraft was designed to fly up to five times over 30 days. In April 2021, it became the first manmade object to achieve powered, controlled flight on the surface of another planet, following up its maiden voyage with a dazzling total of 72 flights.

"The historic journey of Ingenuity, the first aircraft on another planet, has come to end," said NASA administrator Bill Nelson in a statement, commemorating the spacecraft's achievement. "That remarkable helicopter flew higher and farther than we ever imagined and helped NASA do what we do best – make the impossible, possible."

More on Ingenuity: NASA's Mars Helicopter Has Died


NASA to 'wiggle' broken Ingenuity Mars helicopter's blades to analyze damage

Brett Tingley
Thu, February 1, 2024 at 6:00 AM MST·3 min read

A small helicopter sits in red rocky dirt.


Ingenuity's mission is officially coming to an end, but not before mission scientists try to determine how much damage the helicopter suffered.

NASA held a livestream Wednesday (Jan. 31) to pay tribute to Mars helicopter Ingenuity, which suffered rotor damage on its most recent flight. During the livestream, mission managers revealed that all four of Ingenuity's blades were damaged during a rough landing on the Red Planet surface.

Teddy Tzanetos, Ingenuity Project Manager, said that NASA and JPL still aren't sure what caused the damage to Ingenuity's blades; it remains unclear whether the helicopter's power dipped during landing, causing unwanted ground contact, or if it accidentally struck the ground to cause a "brownout."

Tzanetos added that NASA and the Jet Propulsion Laboratory (JPL) will slowly rotate the helicopter's blades and "wiggle" them, or adjust their angle, while collecting video in order to allow the team to determine the extent of Ingenuity's damage. However, Tzanetos said that no matter what such imaging will show, the dual-rotor drone has flown its last flight and will soon end its mission.

"Helicopters like this are not designed to fly even with the smallest fraction of a grant of imbalance and we're gonna have the end of our mission in the weeks ahead," Tzanetos said during the livestream.

Related: 'It's sort of been invincible until this moment:' Mars helicopter Ingenuity pilot says 'bland' terrain may have doomed NASA chopper

During the NASA Science Live webcast, Tzanetos and Tiffany Morgan, NASA's Mars Exploration Program Deputy Director, sang the praises of the plucky 'copter. Morgan described how Ingenuity proved to be a valuable companion for the Perseverance rover, with whom it has been exploring Mars since the pair landed on Feb. 18, 2021.

The helicopter was initially designed to make just five flights — its mission ended after number 72.

"Not only did it help us with designing for future missions, but it also helped with Perseverance's current mission. It scouted ahead and took a sneak peek at the operations Perseverance is going to experience, and that allowed the planners to navigate the terrain as well as to identify potentially compelling science targets," Morgan said.

The fact that Ingenuity was able to fly in the thin Martian atmosphere and carry out as many sorties as it did is a true testament to JPL's expertise and could foreshadow future missions, she added.

"The NASA JPL team didn't just demonstrate the technology, they demonstrated an approach that if we use in the future will really help us to explore other planets and be as awe-inspiring, as amazing, as Ingenuity has been," Morgan said.

RELATED STORIES:

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The helicopter far exceeded the agency's expectations, especially given the fact that it was built with off-the-shelf commercial cell phone components and represented a largely unknown premise: Flying an aircraft on another planet.

"We couldn't be prouder or happier with how our little baby has done," Tzanetos said. "It's been the mission of a lifetime for all of us. And I wanted to say thank you to all of the people here that gave their weekends, their late nights. All the engineers, the aerodynamic scientists, the technicians who hand-crafted this aircraft."

Morgan added that NASA is already envisioning using future helicopters on other planets or celestial bodies that will be built on the foundation that Ingenuity has laid and the knowledge the agency has gained from this completed mission.

"I really look forward to the future and what we can do with with the offspring of Ingenuity," she said.


RIP Ingenuity: NASA's space helicopter may be dead, but the agency's next gen are nearing lift-off

Rae Hodge
Wed, January 31, 2024 

Concept for NASA Mars helicopters NASA/ESA/JPL-Caltech


Last week, one of the most innovative missions in space exploration came to a bitter end. NASA’s famously successful Ingenuity rotorcraft — the 3.5-pound helicopter-like robot collecting samples on Mars — finally came to a crashing end. But already NASA and the European Space Agency are looking ahead to the next generation of space helicopters.

More robust than its predecessor, with at least 66 test flights under its belt and a new dual-rotor system, and carbon-fiber blades that can nearly reach Mach 1 speeds — the heir to Ingenuity has been preparing to take over its predecessor’s mission inside the agency’s 25-foot space simulator at the Jet Propulsion Lab in Pasadena, California.

Ingenuity was the first aircraft to make a powered, controlled flight on another planet. And though it was originally planned for only five flights, the helicopter made it 14 times farther in distance than NASA thought it would, logging more than two hours of airtime in its 72 successful flights on Mars.

“It is bittersweet that I must announce that Ingenuity, the little helicopter that could — and it kept saying ‘I think I can, I think I can!’ — well, it has now taken its last flight on Mars,” said NASA Administrator Bill Nelson in a Friday appearance, who compared the craft’s historical flight achievements to those of the Wright brothers in 1903.

“What Ingenuity accomplished far exceeds what we thought was possible,” Nelson said. “And helped NASA do what we do best – make the impossible, possible. Through missions like Ingenuity, NASA is paving the way for future flight in our solar system and smarter, safer human exploration to Mars and beyond.”

Nelson said the fatal blow to Ingenuity came when the craft’s carbon fiber wings — fighting for lift through the planet’s exceedingly thin atmosphere, which is just 1% as dense as Earth’s — sustained damage during a landing. Nelson said the agency is investigating the possibility that the rotor blade struck the ground.



Now, hopes are high for the next generation of helicopters on the red planet. Called Sample Recovery Helicopters (SRH), NASA’s new craft are about the size of Ingenuity but have new dual, carbon-fiber rotors with a wingspan about four inches longer than Ingenuity’s. They’re stronger too, and designed with higher speeds in mind, having already undergone at least 66 test flights with the benefit of Ingenuity’s off-world data.

“Over three weeks, the carbon-fiber blades were spun up at ever-higher speeds and greater pitch angles to see if they would remain intact as their tips approached supersonic speeds. Longer and stronger than those used on NASA’s Ingenuity Mars Helicopter, the blades reached Mach 0.95 during the test,” NASA said in November.

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Tyler Del Sesto is NASA’s deputy test conductor for the SRH at the Jet Propulsion Lab. After seeing the SRH perform in the lab’s 25-foot wide, 85-foot-tall space simulator, he’s confident about the new fleet.

“We spun our blades up to 3,500 rpm, which is 750 revolutions per minute faster than the Ingenuity blades have gone,” he said in a November statement. “These more efficient blades are now more than a hypothetical exercise. They are ready to fly.”

Powered by solar panels that charge its internal batteries, and equipped with grabber arms and ground-ready wheels, the SRH are being aimed at a landing site near the Perserverance’s rover’s own, in the Jerezo Crater. The rotorcraft would launch from Earth in 2028, arrive on Mars in 2030, and then — fortune prevailing — make it home with its Martial samples in tow by 2033.

“The Sample Recovery Helicopters would expand on Ingenuity's design, adding wheels and gripping capabilities to pick up cached sample tubes left on the surface by Perseverance and transport them to the Sample Retrieval Lander,” according to the the agency’s latest spec sheets.

To get the SRH on the surface safely, NASA is also aiming to premiere its beefy new lander. The Sample Retrieval Lander would be about “the size of an average two-car garage," weighing 7,440 pounds and currently slated to carry two of the SRH. The new lander would also be the first ever to bring along a rocket along for the ride, NASA’s Mars Ascent Vehicle. Once the lander arrives, NASA’s Perseverance rover would carry its collection of Martian sample tubes to the Sample Retrieval Lander. The SRH would take off and collect any Martian sample tubes that Perseverance left behind.

“Each helicopter would follow a four-day procedure to recover sample tubes. Day one: fly to an area near the sample tube. Day two: drive close to the tube and pick it up. Day three: fly back to an area near the Sample Retrieval Lander. Day four: drive close to the lander and drop the tube in the workspace of the lander's Sample Transfer Arm,” the agency said.

But the SRH aren’t the only craft in the works. And the greater leap of innovation among Ingenuity’s descendents may arrive much sooner, with the ambitious Dragonfly mission to Saturn’s moon Titan. The mission is approved for a readiness date in July 2028, and aims to send a “car-sized nuclear-powered drone” toward the icy surface of Titan, then land on its sands, which will be built and operated by Johns Hopkins Applied Physics Laboratory.

Dragonfly’s principal investigator, Elizabeth Turtle, recently said the mission is ready to move ahead after an impressive set of test results in the facility’s 3,000-cubic-foot Titan testing chamber.

“Dragonfly is such a daring endeavor, like nothing that has ever been done before,” she said in a statement. “We’ve demonstrated that we’re ready for the next steps on the path to Titan, and we’ll keep moving forward with the same curiosity and creativity that have brought Dragonfly to this point.”

Of course, 2028 is still some time away. If you want to make your own Mars helicopter, NASA’s JPL has a YouTube video that will walk you through building your own functional tribute to Ingenuity out of paper. Until then, you can watch the JPL crew give its final farewell to the small-but-mighty Martian-copter in their tribute video below.




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