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Signs of first planet found outside our galaxy – Yahoo News Canada

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The finding comes from observation of an X-ray binary – a neutron star or black hole pulling in gas from a companion star

Astronomers have found hints of what could be the first planet ever to be discovered outside our galaxy.

Nearly 5,000 “exoplanets” – worlds orbiting stars beyond our Sun – have been found so far, but all of these have been located within the Milky Way galaxy.

The possible planet signal discovered by Nasa’s Chandra X-Ray Telescope is in the Messier 51 galaxy.

This is located some 28 million light-years away from the Milky Way.

This new result is based on transits, where the passage of a planet in front of a star blocks some of the star’s light and yields a characteristic dip in brightness that can be detected by telescopes.

This general technique has already been used to find thousands of exoplanets.

Dr Rosanne Di Stefano and colleagues searched for dips in the brightness of X-rays received from a type of object known as an X-ray bright binary.

These objects typically contain a neutron star or black hole pulling in gas from a closely orbiting companion star. The material near the neutron star or black hole becomes superheated and glows at X-ray wavelengths.

Because the region producing bright X-rays is small, a planet passing in front of it could block most or all of the X-rays, making the transit easier to spot.

The team members used this technique to detect the exoplanet candidate in a binary system called M51-ULS-1.

“The method we developed and employed is the only presently implementable method to discover planetary systems in other galaxies,” Dr Di Stefano, from the Harvard-Smithsonian Center for Astrophysics in Cambridge, US, told BBC News.

“It is a unique method, uniquely well-suited to finding planets around X-ray binaries at any distance from which we can measure a light curve.”

Future planet-hunting

This binary contains a black hole or neutron star orbiting a companion star with a mass about 20 times that of the Sun. A neutron star is the collapsed core of what had once been a massive star.

The transit lasted about three hours, during which the X-ray emission decreased to zero. Based on this and other information, the astronomers estimate that the candidate planet would be around the size of Saturn, and orbit the neutron star or black hole at about twice the distance Saturn lies from the Sun.

Dr Di Stefano said the techniques that have been so successful for finding exoplanets in the Milky Way break down when observing other galaxies. This is partly because the great distances involved reduce the amount of light which reaches the telescope and also mean that many objects are crowded into a small space (as viewed from Earth), making it difficult to resolve individual stars.

With X-rays, she said, “there may be only several dozen sources spread out over the entire galaxy, so we can resolve them. In addition, a subset of these are so bright in X-rays that we can measure their light curves.

“Finally, the huge emission of X-rays comes from a small region that can be substantially or (as in our case) totally blocked by a passing planet.”

Messier 51Messier 51

Messier 51 is also called the Whirlpool Galaxy because of its distinctive spiral shape

The researchers freely admit that more data is needed to verify their interpretation.

One challenge is that the planet candidate’s large orbit means it would not cross in front of its binary partner again for about 70 years, quashing any attempts to make a follow-up observation in the near-term.

One other possible explanation that the astronomers considered is that the dimming has been caused by a cloud of gas and dust passing in front of the X-ray source.

However, they think this is unlikely, because the characteristics of the event do not match up with the properties of a gas cloud.

“We know we are making an exciting and bold claim so we expect that other astronomers will look at it very carefully,” said co-author Julia Berndtsson of Princeton University, New Jersey.

“We think we have a strong argument, and this process is how science works.”

Dr Di Stefano said that the new generation of optical and infrared telescopes would not be able to compensate for the problems of crowding and dimness, so observations at X-ray wavelengths would likely remain the primary method for detecting planets in other galaxies.

However, she said a method known as microlensing might also hold promise for identifying extra-galactic planets.

The study has been published in the peer-reviewed journal Nature Astronomy.

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Citing debris risk, NASA delays spacewalk to fix space station antenna – Financial Post

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A spacewalk planned for Tuesday to repair a faulty antenna on the International Space Station was postponed indefinitely, NASA said, citing a “debris notification” it received for the orbiting research laboratory.

Two U.S. astronauts had been scheduled to venture outside the space station at 7:10 a.m. Eastern time (1210 GMT) to begin their work, facing what NASA officials had called a slightly elevated risk posed by debris from a Russian anti-satellite missile test this month.

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But about five hours before the outing was to have commenced, NASA said on Twitter that the spacewalk had been called off for the time being.

“NASA received a debris notification for the space station. Due to the lack of opportunity to properly assess the risk it could pose to the astronauts, teams have decided to delay the Nov. 30 spacewalk until more information is available,” the space agency tweeted.

It was not made clear how close debris had come to the space station, orbiting about 250 miles (402 km) above the Earth, or whether it was related to the Russian missile test.

NASA TV had planned to provide live coverage of the 6-1/2-hour “extravehicular activity,” or EVA, operation by astronauts Thomas Marshburn and Kayla Brown. The outing would be the fifth spacewalk for Marshburn, 61, a medical doctor and former flight surgeon with two previous trips to orbit, and the first for Barron, 34, a U.S. Navy submarine officer and nuclear engineer on her debut spaceflight for NASA.

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The objective is to remove a faulty S-band radio communications antenna assembly, now more than 20 years old, and replace it with a new spare stowed outside the space station.

According to plans, Marshburn was to have worked with Barron while positioned at the end of a robotic arm operated from inside the station by German astronaut Matthias Maurer of the European Space Agency, with help from NASA crewmate Raja Chari.

The four arrived at the space station Nov. 11 in a SpaceX Crew Dragon capsule launched from the Kennedy Space Center in Cape Canaveral, Florida, joining two Russian cosmonauts and a NASA astronaut already aboard the orbiting outpost.

Four days later, an anti-satellite missile test conducted without warning by Russia generated a debris field in low-Earth orbit, and all seven crew members took shelter in their docked spaceships to allow for a quick getaway until the immediate danger passed, according to NASA.

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The residual debris cloud from the blasted satellite has dispersed since then, according to Dana Weigel, NASA deputy manager of the International Space Station (ISS) program.

But NASA calculates that remaining fragments continued to pose a “slightly elevated” background risk to the space station as a whole, and a 7% higher risk of spacewalkers’ suits being punctured, as compared to before Russia’s missile test, Weigel told reporters on Monday.

Although NASA has yet to fully quantify additional hazards posed by more than 1,700 larger fragments it is tracking around the station’s orbit, the 7% higher risk to spacewalkers falls “well within” fluctuations previously seen in “the natural environment,” Weigel said.

Still, mission managers canceled several smaller maintenance tasks under consideration for Tuesday’s spacewalk, Weigel added. (By Steve Gorman. Editing by Gerry Doyle)

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A new approach to flagship space telescopes – The Space Review

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The astrophysics decadal survey recommended a scaled-down version of a space telescope concept called LUVOIR as the first in a line of flagship space observatories to be developed over the next few decades. (credit: NASA/GSFC)

For much of this year, the biggest puzzle for astrophysicists had nothing to do with dark matter, dark energy, or discrepancies in the value of the Hubble Constant. Instead, the question at the top of their minds was: when was Astro2020 coming out?

Astro2020 was the shorthand for the latest astrophysics decadal survey, the once-a-decade review of the state of the field and recommendations for both ground- and space-based projects to pursue to answer the top scientific questions. The final report by the decadal survey’s steering committee, once expected in late 2020 as the name suggests, had slipped to some time in 2021 because of the pandemic, which forced a shift from in-person to virtual meetings just as work on the survey was going into high gear.

The decision to pick a concept between LUVOIR and HabEx was driven by science and budgets: big enough to do meet key science objectives like characterizing exoplanets, but also small enough to fit into a reasonable cost and schedule.

The committee itself kept quiet about its work, providing little specific guidance about when to expect the final report. At a meeting of NASA’s Astrophysics Advisory Committee in October, Paul Hertz, director of the agency’s astrophysics division, presented the results of an office pool from earlier in the year predicting when the report would be released. All but two thought the report would have already been released by the mid-October meeting of that committee; those two predicted it would be released the week of Thanksgiving.

Fortunately, they and the rest of the astrophysics community did not have to wait until last week’s holiday to get their hands on the report. The document, released November 4, provided astronomers with a long-awaited roadmap for not just the next decade but arguably through the middle of the century, endorsing a set of observatories that can peer back into the distant early universe and also look for habitable worlds close to home.

While the decadal survey makes a series of recommendations for smaller missions and ground-based telescopes, what gets the most attention is its recommendation for a large strategic, or flagship, space mission. That recommendation is just that—NASA isn’t bound to accept it—yet the agency has adopted the top-ranked flagship missions of previous decadals. That includes the one picked in the previous decadal in 2010, which became the Wide-Field Infrared Survey Telescope (WFIRST), renamed by NASA to the Nancy Grace Roman Space Telescope last year.

NASA, in preparation for Astro2020, commissioned detailed studies of four proposed flagship observatories, operating from far infrared to X-ray wavelengths (see “Selecting the next great space observatory”, The Space Review, January 21, 2019.) These studies offered detailed technical, scientific, and budgetary information for the concepts, which were effectively finalists for the being the next flagship mission—although the decadal survey was not under any obligation to pick one.

And, in the end, they didn’t pick one of the four. Instead, the recommended flagship mission was something of a compromise between two of the concepts. One, the Habitable Exoplanet Observatory, or HabEx, proposed a space telescope between 3.2 and 4 meters across optimized to search for potentially habitable exoplanets. The other, the Large Ultraviolet Optical Infrared Surveyor, or LUVOIR, proposed a large space telescope between 8 and 15 meters across for use in a wide range of astrophysics, from exoplanet studies to cosmology.

What the decadal recommended was a telescope six meters across capable of observations in ultraviolet, visible, and infrared wavelengths: similar to LUVOIR but scaled down to a size between the smaller version of LUVOIR and HabEx.

The decision to pick a concept between LUVOIR and HabEx was driven by science and budgets: big enough to do meet key science objectives like characterizing exoplanets, but also small enough to fit into a reasonable cost and schedule. “We thought that six meters provides assurance of enough target planets, but it’s also a big enough gain in capability over Hubble to really enable general astrophysics,” said Robert Kennicutt, an astronomer at the University of Arizona and Texas A&M University who was one of the two co-chairs of the decadal survey committee.

“We realized that all of these are visionary ideas but they require timelines that are pan-decadal, even multi-generational,” said Harrison. “We really think a different approach needs to be taken.”

That telescope—not given a name by the decadal survey—will still be expensive and take a long time to build. The decadal’s estimates, which included independent cost and schedule analyses, projected the telescope would cost $11 billion to build, in line with the James Webb Space Telescope when accounting for inflation, and be ready for launch in the first half of the 2040s. But the original LUVOIR concept would have cost $17 billion and not be ready until the 2050s, according to those same analyses. HabEx, the decadal survey concluded, would have been cheaper but too small to meet many of those science goals.

That selection of a flagship mission was, alone, not that different than past decadal surveys. Even that compromise pick is not unprecedented, as the previous decadal’s recommendation of what would become Roman emerged from combining several concepts. What was different, though, was the realization that, after the delays and cost overruns suffered by past flagships, notably the James Webb Space Telescope, NASA needed a different approach to developing such missions.

“We realized that all of these are visionary ideas but they require timelines that are pan-decadal, even multi-generational,” said Fiona Harrison of Caltech, the other co-chair of the steering committee, referring to the four flagship concepts studied for the decadal. “We really think a different approach needs to be taken.”

What the decadal survey recommended was that the space telescope it recommended be just the first mission to emerge from a new Great Observatories Mission and Technology Maturation Program at NASA. That program would mature technologies for a series of flagship missions in a coherent fashion.

“The survey committee expects that this process will result in decreased cost and risk and enable more frequent launches of flagship missions, even if it does require significantly more upfront investment prior to a decadal recommendation regarding implementation,” the committee concluded in the report.

Specifically, it recommended that, five years after starting work on the large space telescope that was the report’s top priority, NASA begin studies of two other flagship missions, a far infrared space telescope and an X-ray observatory, at estimated costs of $3–5 billion each. Both are similar to the other two flagship mission concepts studied by NASA for this decadal survey, the Origins Space Telescope and Lynx X-ray Observatory.

Setting up studies of those future mission concepts, without committing to them, allows NASA to adapt if both technologies or science goals change, another member of the decadal survey steering committee noted. “If the progress appears to be stalled or delayed, then we can rapidly onramp another one of the compelling, exciting ideas,” said Keivan Stassun of Vanderbilt University. “We can be phasing in multiple great ideas.”

“We were tasked and encouraged by the funding agencies, including NASA, to really think big, bold, ambitious, and long-term,” Stassun said.

The idea that it takes a long time to develop flagship space telescopes is not new: the first studies of JWST, originally called the Next Generation Space Telescope, predate the launch of the Hubble Space Telescope more than three decades ago, and that spacecraft is only now about to launch. But the study’s proposal recognizes that the problems experienced by JWST and, to a lesser extent, Roman, require a different approach to managing such complex, expensive missions.

It also reflects the realization that some of the questions that astrophysics is seeking to answer can’t be easily fit into decade-long timeframes. “We were tasked and encouraged by the funding agencies, including NASA, to really think big, bold, ambitious, and long-term,” Stassun said. “We took that to mean that we should not be thinking only about that which can be accomplished in a ten-year period.”

NASA’s Hertz had, in fact, urged the decadal survey to be bold on many occasions before and during its deliberations. “I asked the decadal survey to be ambitious, and I believe they are certainly ambitious,” he said at a November 8 meeting of the Committee on Astronomy and Astrophysics of the National Academies’ Space Studies Board.

NASA is only starting to review the overall recommendations of the decadal, he said. That includes not just its analysis of flagship missions but endorsement of a new medium-class line of “probe” missions, with a cost of $1.5 billion per mission and flying once a decade. Such missions would be analogous to the New Frontiers line of planetary science missions that fall between planetary science flagships and smaller Discovery class missions.

The delay in completing the decadal means it won’t have an impact on NASA’s next budget proposal for fiscal year 2023, which is already in active development for release in early 2022. Hertz said he’ll provide some initial comment on the decadal at a town hall meeting during the American Astronomical Society meeting in early January, particularly any recommendations that can be accommodated in the fiscal year 2022 budget. A complete, formal response will come later next year after a series of town hall meetings.

Those plans will depend on budgets. The first views Congress has on the decadal, including its flagship mission plans, will come Wednesday when the House Science Committee’s space subcommittee holds a hearing on the report.

Hertz was optimistic in general about the state of NASA’s astrophysics programs, citing the impending launch of JWST and Roman passing its critical design review. “I’m really excited. This is a great time for astrophysics,” he said. Astronomers hope the decadal’s recommendations, if implemented, can make it a great few decades for the field.


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AI Just Designed The World’s First Living Robots That Can Make Babies – Forbes

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Xenobots are the world’s first AI-designed biological robots that can self-repair and self-replicate.

The year was 1948 when Hungarian-American mathematician John von Neumann proposed the idea of an autonomous robot capable of using raw materials to reproduce itself. Today, Neumann’s vision is finally realized with one major twist: the self-replicating robot isn’t made of aluminum, plastics, spur gears or sprockets. The parent robot and its babies, a new lineage of organism called Xenobots, are entirely biological. “It was exciting to see that we could [make] this Von Neumann machine, but using cells instead of robot parts,” says co-author Sam Kriegman, computer scientist at the Wyss Institute at Harvard and co-author of the Xenobots paper published today in PNAS.

“People have philosophized about this forever,” says Joshua Bongard, senior author and computer scientist at the University of Vermont. “But now you can actually do experiments to create biological machines, or machines that make biology, which in turn make machines.” 

It’s okay to be confused. The researchers liberally refer to Xenobots as “machines” even though Xenobots don’t contain a single mechanical component. Science may be moving faster than our framework for talking and even thinking about this new category of machine life. “I think it challenges us to see that there may not be a clear dividing line between machine and organism,” says Bongard.

Artificial Intelligence

The self-replicating Xenobot was first “conceived” by an artificial intelligence (AI) program working on UVM’s supercomputer. The AI ran an evolutionary algorithm capable of testing billions of biological body shapes in a simulation. The goal was to discover which configuration of cells is capable of self-replication. The AI rendered a winning design: a cluster of cells shaped like Pac-Man from the 1980s arcade game.

Biologist Douglas Blackiston took the AI’s blueprint and used microcautery electrodes and surgical forceps to hand-sculpt the Xenobots, creatures made up of clusters of 4,000-5,000 frog cells swimming in a petri dish. Random frog cells added to the dish give the parent Xenobots raw material to make babies inside their Pac-Man-shaped mouths. The Xenobabies grow into parent Xenobots. By adding frog cells, self-replication continues generation after generation.

Biological Intelligence

Sculpting a bespoke shape out of stem cells is the “programming” that instructs cell clusters to develop a certain way. Shaping a cluster of frog cells in this specific configuration programs them to become a new self-replicating life form. “This is an AI designing life, or designing a robot, whatever you want to call it,” says Blackiston. “These are things that are not under the purview of [natural] selection.” 

New Definitions For Intelligence

Robots made of traditional robot parts that perform quite well in controlled environments often fail in the real world. “Once you move through the world, it’s unpredictable, things are messy,” says Kriegman, who was delighted by the possibility of using robotics materials that have biological intelligence built in. “Doug came up with the notion of building robots out of biological stuff,” says Kriegman. “You get this intelligence for free. And we were off to the races.”

When asked if Xenobots are intelligent, Blackiston has reservations. Of the two computer scientists and two biologists on the research team, Blackiston is more comfortable calling Xenobots programmed engineered organisms with intelligence happening at the design and programming level but not in the actual Xenobot. “My opinion is that they’re not intelligent,” says Blackiston. Though he agrees with the rest of the team that their work challenges scientific definitions. “[Definitions] are being driven into extinction because of these technologies,” says Bongard. “Xenobots are a product of AI and AI itself is helping to drive to extinction our standard definitions of intelligence.”

Intelligent Design

Definitions aside, Blackiston thinks society will have to grapple with many of the applications for, and implications of, this new technology—like the question of artificial intelligence designing replacement parts for humans. “What if an AI tinkers around and figures out it can design a better heart than the one that evolution has given us?” Asks Blackiston, who thinks it’s possible AI could give us blueprints to create superior organs to our current models. “I think we’re going to see these questions popping up all over the medical and environmental space in the next 10-15 years.”

Blackiston surgically shaping the first generation of AI-designed Xenobot:

Xenobots collect frog cells and shaping them into Xenobabies:

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