Wednesday, November 20, 2024

How Could Astronauts Call for Help from the Moon?

Exploring the Moon poses significant risks, with its extreme environment and hazardous terrain presenting numerous challenges. In the event of a major accident, assistance might take days or even weeks to arrive. To address this, Australian researchers have created a distress alert system based upon the COSPAS-SARSAT technology used for Earth-based search and rescue operations. It relies on low-power emergency beacons that astronauts could activate with minimal setup and use a planned lunar satellite network for communication and rescue coordination.

Fortunately I have never had to raise a distress call. I can imagine it though, somewhere remote, some sort of accident perhaps and need to summon assistance. Even on Earth, most mobile phone systems will be able to use a satellite signal to get a message out even if no cell signal. It’s not so easy on the Moon.  Even communication is delayed by just over a second but if someone needs to come and help, then you are really in trouble. That’s what the team from Australia identified and have addressed in their paper published in October 2024. 

Aldrin on the Moon. Astronaut Buzz Aldrin walks on the surface of the moon near the leg of the lunar module Eagle during the Apollo 11 mission. Mission commander Neil Armstrong took this photograph with a 70mm lunar surface camera. While astronauts Armstrong and Aldrin explored the Sea of Tranquility region of the moon, astronaut Michael Collins remained with the command and service modules in lunar orbit. Image Credit: NASA

As part of NASA’s Artemis program (which aims to create a sustained human presence on the Moon) astronauts will face significant dangers in isolated regions such as the lunar south pole. To address these challenges, researchers at the University of South Australia (UniSA) have been leading a project focused on developing an emergency response system. It’s designed to deliver critical safety warnings, enable incident reporting, and track the locations of astronauts that may be in trouble. 

NASA’s Space Launch System rocket carrying the Orion spacecraft launches on the Artemis I flight test, Wednesday, Nov. 16, 2022, from Launch Complex 39B at NASA’s Kennedy Space Center in Florida. Credit: NASA/Joel Kowsky.

The Artemis program is the focus of returning humans to the Moon. If successful it will mark the first crewed lunar missions since the days of the Apollo missions. With a focus on exploration and scientific discovery, Artemis aims to land astronauts, including the first woman and the first person of colour, on the Moon’s surface in 2025.

Scientists from Adelaide and the United States are collaborating to develop a satellite constellation – like those launched by SpaceX but on a smaller scale – dedicated to improving communication and navigation on the Moon. The system will allow astronauts to transmit emergency alerts to a network of satellites which will then forward the data to Earth or nearby lunar stations.

Founder of Safety from Space and adjunct researcher Dr Mark Rice explains that the system can provide continuous communication with astronauts for up to 10 hours! Even if they are in mountainous or heavily cratered terrain, the system will perform well. The group Safety from Space was formed in 2018 and has been awarded $100,000 from the Government to help with lunar search and rescue (LSAR) initiatives. The trial aims to provide astronauts with a lighter, more reliable radio beacon with a much longer battery life.

If successful, the solution could enable significant Australian contributions to the Artemis program. It could even help to improve emergency communications here on Earth, especially in areas where mobile phone signals are not reliable. 

Source : New lunar distress system could safeguard future astronauts

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There Was a 15 Minute Warning Before Tonga Volcano Exploded

Volcanoes are not restricted to the land, there are many undersea versions. One such undersea volcano known as Hunga Tonga-Hunga Ha’apai off the coast of Tonga. On 15th January 2022, it underwent an eruption which was one of the most powerful in recent memory. A recent paper shows that seismic waves were released 15 minutes before the eruption and before any visible disruption at the surface. The waves had been detected by a seismic station 750km away. This is the first time a precursor signal has been detected. 

Undersea volcanoes are openings in the Earth’s crust beneath the ocean, where magma from the mantle escapes, triggering eruptions. They are surprisingly common, with most of Earth’s volcanic activity occurring underwater, particularly along mid-ocean ridges and subduction zones. They play a vital role in creating new seafloor through seafloor spreading, as magma cools and solidifies into basaltic crust. Some grow so tall that they rise above the ocean’s surface, forming volcanic islands such as Iceland and Hawaii. Their eruptions release significant amounts of gas, heat, and minerals into the surrounding water, shaping marine ecosystems.

An erupting undersea volcano forms a new island off the coast of Nishinoshima, a small unihabited island in the southern Ogasawara chain of islands. The image was taken on November 21, 2013 by the Japanese Coast Guard.

The Hunga Tonga-Hunga Ha’apai volcano is an undersea volcano located in the South Pacific. It became well known after its massive eruption in January 2022. The eruption was one of the most powerful volcanic events of the 21st century, triggering tsunamis that affected coastlines as far away as Japan and the Americas. The explosion released a plume of ash, gas, and water vapour, reaching over 50 kilometres into the atmosphere, making it the highest plume ever recorded. It impacted global weather patterns and temporarily increased water vapour in the stratosphere.

The eruption of January 2022 formed a caldera on Hunga Tonga-Hunga Ha’apai. There were disturbances that were recorded by many surface stations and satellites in orbit. The data which had been captured revealed that the eruptions began just after 04:00 UTC on 15 January. There were a number of reports of seismic waves from around 15 minutes before the onset of eruption. In a paper published recently by lead author Takuro Horiuchi and a team from the University of Tokyo, they explore the wave detection and mechanics of the eruption. 

Volcanic eruptions at Mt. Etna from orbiting NASA Terra Satellite. Acquired on January 11, 2011. NASA Earth Observatory Image of the Day on January 15, 2011. Credit: NASA Terra Satellite

The team aim to confirm that the event actually occurred just before the 04:00 published timestamp. If they can confirm this, it will help understand the processes that led to the violent eruption. At the time of the eruption, no seismic stations had been working on Tonga but data had been recorded as far away as Fiji and Futuna, both of which around 750km away from the volcano. 

The study concluded that the waves which had been detected were Rayleigh waves – a type of seismic waves which are a combination of compression (longitudinal) and shearing (vertical) movements. The waves started around 03:45 on the 15th January 15 minutes before the onset of the eruption. This is the first time significant seismic activity has been seen before the eruption event. It demonstrates that seismic stations hundreds of kilometres away can be positively used to detect signals as precursors to eruptions.

Source : A Seismic Precursor 15 min Before the Giant Eruption of Hunga Tonga-Hunga Ha’apai Volcano on 15 January 2022

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Main Sequence and White Dwarf Binaries are Hiding in Plain Sight

Some binary stars are unusual. They contain a main sequence star like our Sun, while the other is a “dead” white dwarf star that left fusion behind and emanates only residual heat. When the main sequence star ages into a red giant, the two stars share a common envelope.

This common envelope phase is a big mystery in astrophysics, and to understand what’s happening, astronomers are building a catalogue of main sequence-white dwarf binaries.

Common envelope (CE) binaries are important because they’re the progenitors for Type 1a supernovae. When the main sequence star swells into a red giant, the compact and gravitationally powerful white dwarf draws matter away from it. This matter gathers on the surface of the white dwarf until it reaches a critical point and then detonates as a supernova.

CE binaries are also important because they can merge and emit gravitational waves, another astrophysical phenomenon that needs better understanding.

In new research, astronomers from the University of Toronto identified 52 candidates with high probabilities of being CE binaries. The research is “The First Catalog of Candidate White Dwarf–Main-sequence Binaries in Open Star Clusters: A New Window into Common Envelope Evolution.” It’s published in the Astrophysical Journal and the lead author is Steffani Grondin, a graduate student in the David A. Dunlap Department for Astronomy & Astrophysics at U of T.

“Despite its importance, CE evolution may be one of the largest uncertainties in binary evolution,” the authors write in their research.

“Binary stars play a huge role in our universe,” said lead author Grondin. “This observational sample marks a key first step in allowing us to trace the full life cycles of binaries and will hopefully allow us to constrain the most mysterious phase of stellar evolution.”

In a Type Ia supernova, a white dwarf (left) draws matter from a companion star until its mass hits a limit, which leads to a supernova explosion. Image Credit: NASA
In a Type Ia supernova, a white dwarf (left) draws matter from a companion star until its mass hits a limit, which leads to a supernova explosion. Image Credit: NASA

The research used massive data sets from three sources: the ESA’s Gaia spacecraft, The Pan-STARRS1 survey, and the 2MASS survey. The team used machine learning techniques to comb the dataset for candidate main sequence-white dwarf (MSWD) binaries in 299 open star clusters in the Milky Way. Open clusters were chosen because they can provide an independent age constraint for the system, allowing the researchers to trace the evolution of the binaries from before the CE phase to after the CE phase. The researchers found 52 high-probability candidates in 38 open clusters.

This number is a huge increase in the number of known MSWD binaries. Only two were known previously. Machine learning is a powerful tool that allows astronomers to work with huge data sets to uncover difficult-to-distinguish results, and this study is no exception.

“The use of machine learning helped us to identify clear signatures for these unique systems that we weren’t able to easily identify with just a few datapoints alone,” says co-author Joshua Speagle, a professor in the David A. Dunlap Department for Astronomy & Astrophysics and Department of Statistical Sciences at U of T. “It also allowed us to automate our search across hundreds of clusters, a task that would have been impossible if we were trying to identify these systems manually.”

Study co-author Maria Drout is also a professor in the David A. Dunlap Department for Astronomy & Astrophysics at U of T. Drout says that the team’s results illustrate how many things in our Universe are “hiding in plain sight” if we only had the tools to see them. As our telescope and survey tools become more discerning and gather larger data sets, our machine-learning tools are making these data sets less opaque.

Drout points out that finding the MSWD binaries in open clusters is the key.

Close-up of the Messier 35 open star cluster. Finding MSWD candidates in open clusters allows astrophysicists to constrain the ages of the binaries. Credit: Wikisky
Close-up of the Messier 35 open star cluster. Finding MSWD candidates in open clusters allows astrophysicists to constrain the ages of the binaries. Credit: Wikisky

“While there are many examples of this type of binary system, very few have the age constraints necessary to fully map their evolutionary history. While there is plenty of work left to confirm and fully characterize these systems, these results will have implications across multiple areas of astrophysics,” Drout explains.

The evolution of CE systems is poorly understood. Astrophysicists don’t know how energy is dissipated during the CE phase, how stellar metallicity affects the development of the CE, or how initial binary parameters predict post-CE orbital configurations. Those are just a few of their unanswered questions.

This study can’t answer all of those questions, but by producing the largest catalogue of MSWD binaries, the team is setting the stage for researchers to make progress.

Grondin and her co-researchers did follow-up spectroscopy on a subset of three systems with the Gemini and Lick observatories. They confirmed two of them to be MSWD binaries.

This figure from the research shows spectra for three high-probability MSWD candidates. The coloured lines are the spectra, and the black lines are representative models of M-type main sequence stars. The authors chose these three as representative samples from their catalogue. They also say that the top panel, from Alessi12-c1, is a clear MSWD binary. Image Credit: Grondin et al. 2024.
This figure from the research shows spectra for three high-probability MSWD candidates. The coloured lines are the spectra, and the black lines are representative models of M-type main sequence stars. The authors chose these three as representative samples from their catalogue. They also say that the top panel, from Alessi12-c1, is a clear MSWD binary, while the bottom two are likely red dwarf white dwarf pairs. Image Credit: Grondin et al. 2024.

They also retrieved archival light curves from TESS, Kepler, and the Zwicky Transient Facility. All three candidates showed clear variability in their light curves. That could indicate rapid M-dwarf rotation or ellipsoidal modulations in a short-period binary. The researchers explain that the catalogue could be contaminated, though not very significantly, by single WDs or MS+MS binaries.

Natal kicks likely influence the results. Many of the MSWD candidates show offsets from their host clusters, suggesting that natal kicks were imparted when the WD formed or during common envelope ejection. Since 78% of the open clusters they observed lacked candidates, the authors think that some MSWD binaries were ejected from their clusters by natal kicks.

“Ultimately, this catalog is a first step to obtaining a set of observational benchmarks to better link post-CE systems to their pre-CE progenitors,” the authors write in their research.

More spectroscopic observations of the candidates will help confirm more of them as MSWD binaries. An expanded search could also help identify MSWD candidates that have been ejected from their clusters by natal kicks.

As is often the case in astronomy and astrophysics, a larger dataset is needed before researchers can reach any conclusions.

“Ultimately, this catalogue is a necessary first step in a larger effort to provide observational constraints on the CE phase,” the authors write, noting that a detailed characterization of some of the candidates in this sample is already underway. The larger sample will allow researchers to link the masses of post-CE binaries with pre-CE progenitors.

“With these observational benchmarks, this sample will aid in efforts to unlock important new insights into one of the most uncertain phases of binary evolution,” the authors conclude.

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What a Misplaced Meteorite Told Us About Mars

11 million years ago, Mars was a frigid, dry, dead world, just like it is now. Something slammed into the unfortunate planet, sending debris into space. A piece of that debris made it to Earth, found its way into a drawer at Purdue University, and then was subsequently forgotten about.

Until 1931, when scientists studied and realized it came directly from Mars. What has it told them about the red planet?

11 million years ago, the Himalayas were rising on a warmer, more humid Earth. Early ape species made their home in an Africa covered by tropical forests. Diverse mammal species roamed the continents.

At the same time, on Mars, the frigid wind blew across a desiccated, forlorn world. The planet’s thin atmosphere is a weak barrier to meteorites, and the planet’s cratered surface bears witness to its nakedness. Some impacts were powerful enough to launch debris into space beyond the planet’s gravitational pull. The meteorite in the drawer is one such piece of debris.

“Many meteoroids are produced by impacts on Mars and other planetary bodies, but only a handful will eventually fall to Earth.”

Marissa Tremblay, Purdue University

The meteorite was long forgotten in its storage place until 1931. Scientists identified it as a piece of Mars, and now new research is uncovering clues about Mars’ past hidden in the 800-gram piece of rock.

This image shows a page from an article published in Popular Astronomy in 1935. Image Credit: Popular Astronomy.
This image shows a page from an article published in Popular Astronomy in 1935. Image Credit: Popular Astronomy.

11 million years ago is not a long time in geological and planetary terms, and the number fits neatly into most people’s imaginations. But rock has deep temporal roots, and the meteorite that reached Earth is an igneous rock that dates back 1.4 billion years. That much time is more difficult to understand, but science is at its best when it opens human minds to a more fulsome understanding of nature.

The meteorite, named “Lafayette” after the city in Indiana that’s home to Purdue University, is the subject of new research published in Geochemical Perspectives Letters. It’s titled “Dating recent aqueous activity on Mars,” and the lead author is Marissa Tremblay. Tremblay is an assistant professor with the Department of Earth, Atmospheric, and Planetary Sciences (EAPS) at Purdue University.

There’s ample evidence that some minerals on Mars formed in the presence of water. Though Lafayette itself is an igneous rock 1.4 billion years old, some of the minerals it contains are younger.

“Dating these minerals can therefore tell us when there was liquid water at or near the surface of Mars in the planet’s geologic past,” Tremblay said. “We dated these minerals in the Martian meteorite Lafayette and found that they formed 742 million years ago. We do not think there was abundant liquid water on the surface of Mars at this time. Instead, we think the water came from the melting of nearby subsurface ice called permafrost, and that the permafrost melting was caused by magmatic activity that still occurs periodically on Mars to the present day.”

Lafayette is one of the Nakhlite meteorites, an igneous rock that formed from basaltic lava around 1.4 billion years ago. Scientists think these rocks formed in one of Mars’ large volcanic regions: Elysium, Syrtis Major Planum, or the largest one, Tharsis, which is home to the three shield volcanoes, Tharsis Montes.

A colourized image of the surface of Mars taken by the Mars Reconnaissance Orbiter. The line of three volcanoes is the Tharsis Montes, with Olympus Mons to the northwest. Valles Marineris is to the east. The researchers think that the Lafayette meteorite came from the Tharsis volcanic region, or one of Mars' other, smaller volcanic regions. Image: NASA/JPL-Caltech/ Arizona State University
A colourized image of the surface of Mars taken by the Mars Reconnaissance Orbiter. The line of three volcanoes is the Tharsis Montes, with Olympus Mons to the northwest. Valles Marineris is to the east. The researchers think that the Lafayette meteorite came from the Tharsis volcanic region, or one of Mars’ other, smaller volcanic regions. Image: NASA/JPL-Caltech/ Arizona State University

Ancient rocks and their embedded minerals contain information about Mars’ ancient past. The history of Mars’ hydrological cycle is a key objective in our ongoing study of Mars. This research is focused on a particular mineral in Lafayette called iddingsite. It forms when basalt is weathered in the presence of water.

The difficulty with meteorites and the clues they contain about ancient Mars is that they’ve been exposed to and potentially altered by the heat of the initial impact and the heat of entry into Earth’s atmosphere. The chemical signals inherent in rock can become muddied. But Lafayette is different. It’s clear that it was blasted off of Mars 11 million years ago.

“We know this because once it was ejected from Mars, the meteorite experienced bombardment by cosmic ray particles in outer space that caused certain isotopes to be produced in Lafayette,” Tremblay says. “Many meteoroids are produced by impacts on Mars and other planetary bodies, but only a handful will eventually fall to Earth.”

“The age could have been affected by the impact that ejected the Lafayette Meteorite from Mars, the heating Lafayette experienced during the 11 million years it was floating out in space, or the heating Lafayette experienced when it fell to Earth and burned up a little bit in Earth’s atmosphere,” Tremblay said. “But we were able to demonstrate that none of these things affected the age of aqueous alteration in Lafayette.”

Study co-author Ryan Ickert is a senior research scientist in Purdue’s EAPS. Ickert uses heavy radioactive and stable isotopes to study geological processes over time. He showed how isotope data used to date water-rock interactions on Mars were problematic and that the data had likely been polluted by other processes. According to Ickert, he and his colleagues got it right this time.

“This meteorite uniquely has evidence that it has reacted with water. The exact date of this was controversial, and our publication dates when water was present,” he says.

This figure from the research shows a cross-section of the Lafayette meteorite. Ol is an olivine grain surrounded by augite crystals (Px). Iddingsite (Id) is present in veins that travel through the rock. Though Lafayette formed over 1.3 billion years ago, the Iddingsite veins formed later, about 742 million years ago, when water seeped through the cracks. Image Credit: Tremblay et al. 2024.
This figure from the research shows a cross-section of the Lafayette meteorite. Ol is an olivine grain surrounded by augite crystals (Px). Iddingsite (Id) is present in veins that travel through the rock. Though Lafayette formed over 1.3 billion years ago, the Iddingsite veins formed later, about 742 million years ago, when water seeped through the cracks. Image Credit: Tremblay et al. 2024.

The researchers used a novel technique involving the isotopes Argon 40 and Argon 39 to date Lafayette’s exposure to water and its formation of Iddingsite. That showed them that the exposure occurred 742 million years ago. Their explanation is that magmatic activity melted subsurface ice, and the water subsequently found its way into cracks in the igneous rock, altering some of the olivine into Iddingsite.

All this from a meteorite that was lost in a drawer.

The Solar System is a puzzle. It’s an artifact of Nature’s ordered complexity, but at the same time, it’s shaped by Nature’s steadfast chaos. Each molecule, each tiny piece of rock, including the Lafayette meteorite, is a part of it. Each piece holds a clue to the puzzle.

“We can identify meteorites by studying what minerals are present in them and the relationships between these minerals inside the meteorite,” said Tremblay. “Meteorites are often denser than Earth rocks, contain metal, and are magnetic. We can also look for things like a fusion crust that forms during entry into Earth’s atmosphere. Finally, we can use the chemistry of meteorites (specifically their oxygen isotope composition) to fingerprint which planetary body they came from or which type of meteorite it belongs to.”

Dating these rocks, these pieces of the puzzle, is difficult. However, this research has made progress by developing a novel way to date minerals in the Lafayette meteorite.

“We have demonstrated a robust way to date alteration minerals in meteorites that can be applied to other meteorites and planetary bodies to understand when liquid water might have been present,” Tremblay concluded.

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SpIRIT CubeSat Demonstrates a Operational Gamma and X-Ray Detector

CubeSats are becoming more and more capable, and it seems like every month, another CubeSat is launched doing something new and novel. So far, technology demonstration has been one of the primary goals of those missions, though the industry is moving into playing an active role in scientific discovery. However, there are still some hurdles to jump before CubeSats have as many scientific tools at their disposal as larger satellites. That is where the Space Industry Responsive Intelligent Thermal (SpIRIT) CubeSat, the first from the Univeristy of Melbourne’s Space Lab, hopes to make an impact. Late in 2023, it launched with a few novel systems to operate new scientific equipment, and its leaders published a paper a few months ago detailing the progress of its mission so far.

SpIRIT represents a first not only for the Melbourne Space Lab but also for Australia as a whole. Their space agency was first set up in 2018 and began funding the SpIRIT project in 2020, as the COVID pandemic started making joint development efforts difficult. To contribute to the nation’s overall learning of how to build and control CubeSat, as much equipment as possible was sourced directly from Australian companies, including an ion drive from Neumann Space and a solar panel platform from Inovor Technologies.

However, the most exciting part of the SpIRIT mission was the instruments explicitly designed for it. There were several interesting ones, including HERMES, an X-ray and gamma-ray detector; TheMIS, a thermal management system used to cool HERMES; LORIS, an edge computing system; and Mercury, for use in low-latency communications.

This video describes the importance of SpIRIT to the Australian space program.
Credit – Australian Space Agency YouTube Channel

Each system is designed to address a specific development problem plaguing CubeSats more generally. They aren’t typically able to capture light in specific wavelengths, such as gamma waves, because the sensors for those wavelengths, which include infrared, require active cooling systems that are too bulky to fit into a CubeSat’s space constraints.

Additionally, the sheer amount of data collected by modern sensors would be overwhelming for the communication links available to standard CubeSats. A single sensor could produce as much as 100Gb of data per day, while a standard downlink channel would allow only 1Gb of data to be sent back to Earth. Combining “edge computing,” where preliminary data processing is done on the CubeSat, with a low-latency communication line is SpIRIT’s solution to that problem. However, TheMIS would also have to deal with the additional heat generated by inefficiencies in the processing unit.

Preliminary results of the project look good, with HERMES beginning complete observations in March and TheMIS successfully managing thermal loads automatically. LORIS has successfully captured some camera images and started performing image recognition algorithms. Mercury has been more of a struggle, with intermittent communication happening throughout the satellite’s lifetime. Since the whole project has primarily been considered a technology demonstration mission, those growing pains are understandable and don’t seem to affect the overall mission operation.

Members of the Spirit Team discuss the development of the project.
Credit – ARES Unimelb YouTube Channel

In addition to technical derisking, many of the lessons the mission operators at the Melbourne Space Lab learned were about managing space projects more generally. Project management and personnel allocation might not be the most interesting topics, but they are necessary for completing a technical project like SpIRIT.

With over 2000 successful CubeSat launches, SpIRIT is another valuable industry contribution. As CubeSats become more widely used as scientific platforms, expect to see more and more efforts like SpIRIT reporting on their progress soon.

Learn More:
Trenti et al. – SpIRIT Mission: In-Orbit Results and Technology Demonstrations
UT – A Gamma Ray Burst Lasted So Long it Triggered a Satellite Twice
UT – A 2022 Gamma Ray Burst Was So Powerful, it was Detected by Spacecraft Across the Solar System
UT – What are CubeSats?

Lead Image:
Depiction of the SpIRIT CubeSat.
Credit – Trenti et al.

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Sun-Like Stars Around Black Holes: What Gives?

Buried in the treasure trove of the Gaia catalog were two strange black hole systems. These were black holes orbiting sun-like stars, a situation that astronomers long thought impossible. Recently a team has proposed a mechanism for creating these kinds of oddballs.

The two black holes, dubbed BH1 and BH2, are each almost ten times the mass of the Sun. That’s not too unusual as black holes go, but what makes these systems strange is that they each have a companion star with roughly the same properties as the Sun. And those stars are orbiting on very wide orbits.

The problem with this setup is that typically sun-like stars don’t survive the transition of a companion turning into a black hole. The end of a giant star’s life is generally violent. When they die, they tend to either eject their smaller companion from the system completely, or just outright swallow them. Either way, we don’t expect small stars to orbit black holes.

But now researchers have a potential solution. They tracked the evolution of extremely massive stars, no smaller than 80 times the mass of the Sun. They found at the end of their lives they eject powerful winds that siphon off enormous amounts of material. This prevents the star from swelling so much that it just swallows its smaller companion. Eventually the star goes supernova and leaves behind a black hole.

Then the researchers studied just how common this kind of scenario is. They found many cases where a sun-like star with a wide enough orbit could survive this transition phase. The key is that the strong winds coming from the larger star have to be powerful enough to limit its late stage violence while still weak enough to not affect the smaller star. The researchers found that this was a surprisingly common scenario and could easily explain the existence of BH2 and BH2.

Based on these results the researchers believe that there might be hundreds of such systems in the Gaia data set that have yet to be discovered. It turns out that the universe is always surprising us and always much more clever than we could ever realize.

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Tuesday, November 19, 2024

Starship’s Booster (and Donald Trump) Make a Splash With Sixth Flight Test

SpaceX’s Starship launch system went through its sixth flight test today, and although the Super Heavy booster missed out on being caught back at its launch pad, the mission checked off a key test objective with President-elect Donald Trump in the audience.

Trump attended the launch at SpaceX’s Starbase complex in the company of SpaceX CEO Elon Musk, who has been serving as a close adviser to the once and future president over the past few months. In a pre-launch posting to his Truth Social media platform, Trump wished good luck to “Elon Musk and the Great Patriots involved in this incredible project.”

Starship is the world’s most powerful rocket, with 33 methane-fueled Raptor engines providing more than 16 million pounds of thrust at liftoff. That’s twice the power of the Saturn V rocket that sent Americans to the moon in the 1960s and early ’70s. The two-stage rocket stands 121 meters (397 feet) tall, with a 9-meter-wide (30-foot-wide) fairing.

Super Heavy had an on-time launch at 4 p.m. CT (22:00 UTC) and was set up to fly itself back to the launch tower to be caught by the giant “Mechazilla” arms that were successfully used during last month’s flight test. But four minutes after liftoff, mission controllers said the booster had to be diverted instead to make a soft splashdown in the Gulf of Mexico. SpaceX didn’t immediately report the reason for the diversion.

“It was not guaranteed that we would be able to make a tower catch today,” launch commentator Kate Tice said during today’s webcast. “So, while we were hoping for it … the safety of the teams and the public and the pad itself are paramount. We are accepting no compromises in any of those areas.”

While the booster settled majestically into the Gulf, the Starship second stage — known as Ship for short — continued on a track that sent it as high as 190 kilometers (120 miles). A plush banana was placed in Ship’s cargo bay as a zero-gravity indicator, and Tice wore a T-shirt bearing the words “It’s Bananas!” to play off the lighthearted theme.

Ship successfully relit one of its methane-fueled Merlin engines while in space, which was a key objective for today’s suborbital test. Relighting the engines under such conditions will be required in the future for Ship’s orbital maneuvers.

A little more than an hour after launch, Ship’s engines fired for a final time to make a controlled splashdown in the Indian Ocean. The daylight visuals, plus other data collected during the flight, will help SpaceX’s team fine-tune Starship’s design for future tests.

SpaceX plans to use Starship to accelerate deployment of its Starlink broadband satellites, as well as to fly missions beyond Earth orbit. The company has a $2.9 billion contract from NASA to provide a version of Starship that’s customized for lunar landings, starting as early 2026. And Musk has said Starship could take on uncrewed missions starting that same year — with the first crewed mission set for launch in 2028 if everything goes right.

NASA Administrator Bill Nelson referred to those future flights in a message on Musk’s X social-media platform:

Check out these other postings tracking the progress of the flight test:

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