The 100 Best Science Photos of 2019 Livescience.com
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For almost 350 years, physicists have been trying to decode Newton’s three-body problem - the problem of figuring out how three similar objects or bodies are going to travel in space in a way that fits in with the laws of motion and gravity. The three laws of motion laid down by Isaac Newton in 1687 are these: objects remain in a state of inertia unless acted upon by force, that the relationship between acceleration and applied force is force equals mass times acceleration (F=ma), and that for every action there is an equal and opposite reaction.
So far, Newton’s basic physics of the universe could be explained. But when the same rules were applied to the Moon, Earth and the Sun, Newton ran into difficulty as it became much harder to track these three original bodies with these mathematical rules. However now, scientists have found fixes for special cases. They’ve found the general formula to be elusive and developed a statistical formula that fits the infamous the ‘oldest open question in astrophysics’ in certain scenarios.
While the researchers point out that they have not come up with an exact, complete solution for the three-body problem, they have cracked a statistical method that covers a lot of these three-body to two-body events, one which can be very useful in helping physicists visualise complicated processes. They looked up a couple of centuries of previous research that puts forward the following idea: in unstable, chaotic three-body systems, one of those bodies eventually gets expelled, leaving behind a stable binary relationship between the remaining two.
As per the study, the researchers applied a probability hypothesis called ergodicity to help guide them to their answers, which uses the principle of averages to work out what's going to happen in a particular system. Importantly, over time, ergodic processes bear little relation to their original state (just like a three-body system). What the new solution does is give scientists an understanding of how the two survivors of a three-body problem are going to behave in a variety of newly stable scenarios. That sort of understanding can be crucial in astrophysics.
Astrophysicist at the Hebrew University of Jerusalem Nicholas Stone reportedly explains, “Take three black holes that are orbiting one another," says Stone. "Their orbits will necessarily become unstable and even after one of them gets kicked out, we're still very interested in the relationship between the surviving black holes."
The 12 Most Important and Stunning Quantum Experiments of 2019 Livescience.com
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SANTA FE, N.M. — The Boeing CST-100 Starliner commercial crew vehicle that flew an abbreviated test flight this month appears to be in good condition as an investigation into the timer problem that shortened the flight continues.
In a Dec. 28 update, Boeing said technicians are continuing processing of the Starliner vehicle that landed Dec. 22 at White Sands Missile Range after a two-day uncrewed test flight. The spacecraft, christened “Calypso” by NASA astronaut Sunita Williams after landing, will be transported back to Boeing’s facilities at the Kennedy Space Center in Florida after the first of the year.
Since that landing, workers have retrieved videos from onboard cameras and other data stored on the spacecraft during the flight. Boeing said it anticipated releasing videos from those onboard cameras in the next week.
Boeing emphasized the good condition of the spacecraft, which showed “little scorching” from reentry and used only a fraction of its onboard propellant reserved for reentry, which the company said confirmed aerodynamic models of the spacecraft. The interior of the Starliner cabin appeared the same after landing as it did before its Dec. 20 launch from Cape Canaveral, the company noted, evidence that “the Starliner’s fully operational life support system functioned as intended and the layout of the interior is well-suited to support crew members in the future.”
The statement, though, provided no updates on the timer problem that turned what was originally an eight-day mission into a two-day one without a planned docking at the International Space Station. The spacecraft’s mission elapsed timer, which is set by communicating with its Atlas 5 rocket prior to liftoff, was off by 11 hours. That caused the spacecraft to think it was on the wrong phase of its mission after separation from the rocket’s upper stage, triggering thruster firings that used excessive amounts of fuel until ground controllers could take over and turn off the thrusters.
Why the timer was off, particularly by such a large amount, any why it wasn’t detected prior to launch is not known. “If I knew, it wouldn’t have happened,” said Jim Chilton, senior vice president for Boeing’s space and launch division, at a Dec. 21 briefing. “We are surprised. A very large body of integrated tests, approved by NASA, didn’t surface this.”
After landing, NASA leadership stated that the problem, once understood and corrected, would not necessarily prevent Boeing from proceeding with a crewed test flight. “It is not something that is going to prevent us from moving forward quickly,” NASA Administrator Jim Bridenstine said at a post-landing briefing Dec. 22. “We can still move forward quickly. We can get it fixed.” He also suggested, though, that the timer problem might lead to a more thorough review of the Starliner’s overall flight software or other systems.
One returned to Florida, the Starliner named Calypso will be refurbished for Boeing’s first post-certification, or operational, mission to the ISS. That mission will carry Williams and fellow NASA astronaut Josh Cassada along with two astronauts yet to be assigned from other ISS partners.
10 Things We Learned About Humans in 2019 Livescience.com
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NASA engineers witnessed their newest Mars rover take its first steps in preparation for its next mission that will search for fossilized remains of ancient life on the red planet.
The test took place inside the Spacecraft Assembly Facility clean room at NASA’s Jet Propulsion Laboratory in Pasadena, California. Engineers clad in white bunny suits—special cleanroom attire worn in order to keep the rover’s delicate instruments very, very clean—watched the yet-to-be-named rover inch forward as part of the crucial pre-flight test, which lasted just over 10-hours.
“Mars 2020 has earned its driver’s license,” Rich Rieber, the lead mobility systems engineer for Mars 2020, said in a news release. “The test unambiguously proved that the rover can operate under its own weight and demonstrated many of the autonomous-navigation functions for the first time. This is a major milestone for Mars 2020.”
During the test, NASA engineers noticed no problems, as the six-wheeled rover successfully performed all its required tasks: it rolled forward and backward and even pirouetted. According to NASA, the rover’s systems, all working in concert, enabled it to steer, turn and drive with ease.
The testing of the vehicle’s autonomous navigation system went well. Since these systems performed perfectly under Earth’s gravity, engineers expect them to perform just as well under Mars’ gravity, which is only 38% of what we experience on Earth.
The test went so well that NASA says the “next time the Mars 2020 rover drives, it will be rolling over Martian soil.” The Mars 2020 rover is scheduled to launch in July 2020, followed by a landing in Jezero Crater on February 18, 2021.
“A rover needs to rove, and Mars 2020 did that,” John McNamee, project manager for Mars 2020, said in a statement. “We can’t wait to put some red Martian dirt under its wheels.”
During its initial test drive, the rover crept forward in small, 3-feet ( 1-meter) increments, enabling the engineers to properly assess its movement and steering abilities. The rover also drove over small ramps designed to simulate uneven Martian terrain.
Engineers were also able to collect data from the vehicle’s Radar Imager for Mars’ Subsurface Experiment (RIMFAX)—an instrument that uses radar waves to scan the ground below the rover. Depending on the terrain, once on Mars, RIMFAX will penetrate the ground, probing the red planet’s subsurface to depths of more than 30-feet (or 10-meters).
Engineers have outfitted the Mars 2020 rover with more durable wheels. Credit: NASA/JPL-Caltech
Curiosity, the Mars 2020 rover’s predecessor currently roaming around on Mars, is predominantly commanded by people back on Earth. However, the rover does have the ability to autonomously choose where to fire its laser spectrometer. As part of its onboard science arsenal, the instrument—called ChemCam—is designed to analyze the chemical composition of nearby rocks and soil.
Mars 2020, on the other hand, will be more independent than any of its predecessors. Equipped with advanced auto-navigation software, the rover will drive with the help of a dedicated onboard computer operating on data collected from the vehicle’s high-resolution, wide-field color cameras.
NASA engineers estimate that the rover will travel an average of 650 feet (200 meters) per day. For comparison, Curiosity’s current distance record for a single day is 702 feet (214 meters), although that’s not typical. The Mars 2020 rover will also be sporting more durable wheels. Curiosity’s wheels are visibly worn after seven years on the Martian surface; engineers hope Mars 2020’s wheels will hold up better.
NASA’s Mars2020 rover will explore Jezero Crater in search of life. Credit: NASA/JPL-Caltech
Once on Mars, the rover will land at Jezero Crater—a former lake bed, rich in mineral deposits known for preserving microfossils here on Earth. In this crater, the rover will search for any signs that life may have once existed on Mars.
While acting as a remote scientist, the rover will unlock clues about the planet’s climate and geology as well as collect samples that will be returned to Earth sometime in the future.
Following the loss of the Opportunity rover, Curiosity has been the sole robot roaming the Martian surface. That will change in 2021, but they won’t be the only ones.
They will be joined by another: The European Space Agency is teaming up with Russia to send their version of the Mars 2020 rover. The Rosalind Franklin ExoMars rover will arrive on Mars at a soon-to-be-announced location, in 2021.
Watch NASA’s Mars 2020 Rover go for a test drive in preparation for landing on Martian soil
NASA astronaut Christina Koch is making history again. Breaking the record for the longest single spaceflight by a woman, Koch will have been in space for 288 days on December 28. She spoke with CNN's Christi Paul about what the record means to her and her work in space.
China developed the powerful rocket, which is designed to carry 25 tons of payload into low orbit, with the aim of launching a Mars probe in 2020.
But the Long March 5 project, originally announced in 2001, suffered lengthy delays due to funding challenges and difficulties in developing new technologies for the first Chinese launcher to fully use liquid propellant.
A second test of the rocket failed in 2017, threatening to delay the country's push to become a leading space power.
Space ambitions
Earlier this year, China completed its first public test of a Mars lander, keeping the country on track for an unmanned exploration mission to the red planet next year.
The country was late to the space race -- it didn't send its first satellite into space until 1970, just after the United States put the first man on the moon.
But in the decades since, China has pumped billions of dollars and other resources into research and training. In addition to the Mars mission, China has been actively pursuing lunar exploration.
The Chang'e-4 lunar probe successfully touched down on the far side of the moon in January, a historic first and major achievement for China's space program.
In 2020, the next lunar mission is due to land on the moon, collect samples and return to Earth, while preliminary plans are underway for a manned lunar mission in the 2030s. If successful, China would become only the second country, after the United States, to put a citizen on the moon.
It also plans to launch a 20-metric-ton space station around 2022.
CNN's Steven Jiang and Lily Lee contributed to this report. CNN's Tara John wrote from London.
Have you noticed that Orion the Hunter—one of the most iconic and familiar of the wintertime constellations—is looking a little… different as of late? The culprit is its upper shoulder star Alpha Orionis, aka Betelgeuse, which is looking markedly faint, the faintest it has been for the 21st century.
When will this nearby supernova candidate pop, and what would look like if it did?
The story starts, as all good astronomy and space stories seem to, on Friday night going into a holiday weekend. We started seeing discussion on Betelgeuse trending on social media on the evening of Friday, December 20th, and dug down to the source of the excitement: a December 8th paper, "The Fainting of the Nearby Red Supergiant Betelgeuse," by researchers at Villanova University. Light curve estimates courtesy of the American Association of Variable Star Observers (AAVSO) verified the assertion that the star had, indeed, faded about one magnitude, or a little over one-half from its usual magnitude +0.5 to +1.5. Noticing the sky was clear, we headed up to our parking garage rooftop observing site in downtown Norfolk, Virginia, to take a look. Betelgeuse was, indeed, noticeably fainter, about a shade dimmer than nearby +1 magnitude Aldebaran.
Now, a change in one magnitude isn't unusual for a variable star such as Betelgeuse. But such a large dip always gives the astronomical community pause. A red giant star 12 times as massive as the sun and about 700 light years distant, the variability of red-orange Betelgeuse was first noted by astronomer Sir John Herschel in 1836. Physically, the star is currently bloated out to a radius of perhaps eight astronomical units (AU). If you plopped it down in the center of our solar system, Betelgeuse might extend all the way out past the orbit of Jupiter.
Our (puny) host star, versus the neighbors, including Betelgeuse. Credit: Dave Dickinson
This fact also allowed astronomers to use the first crude optical interferometric measurements from the 2.5 meter telescope at Mount Wilson Observatory to measure Betelgeuse's physical diameter of 50 milliarcseconds. In the late 1980s, astronomers used an emerging technique of aperture masking interferometry to obtain the first direct 'image' of Betelgeuse.
Betelgeuse is always worth keeping an eye on, as it's one of the closest candidates in our galaxy for a nearby supernova. We see supernovae frequently in distant galaxies, but such an event has not been witnessed in our galaxy in the telescopic era: Kepler's Star in 1604 in the constellation Ophiuchus was the last supernova observed in the Milky Way, though a supernova in the nearby Large Magellanic Cloud put on a good show in 1987. A red giant like Betelgeuse lives fast and dies young, exhausting its supply of hydrogen fuel in just under 10 million years. The star is destined to undergo a core implosion and massive collapse and rebound as a Type II supernova. Such an explosion could occur 100,000 years from now… or tonight.
Is the fading act a prelude to a truly spectacular show, or a false alarm? Astronomers are unsure, but a supernova event just 700-odd light-years away would be an unrepresented opportunity to study one up close. Not only would every optical telescope get trained on the exploding star, but assets such as the Laser Interferometry Gravitational Wave Observatory (LIGO) could detect gravitational waves from a nearby supernova, and neutrino observatories such as Ice Cube buried in the Antarctic ice could detect the event, as well.
A pulsating Betelgeuse in the ultraviolet. Credit: NASA/HST
Fortunately for us, we're safely out of the 50 light-year 'kill zone' for receiving any inbound lethal radiation from Betelgeuse: A supernova would simply be a scientifically interesting event, and put on a good show. Ancient supernovae may have had a hand in the evolution of life on Earth, and a recent study suggests that one might even have forced early humans to walk upright.
What would a supernova in Orion look like? Well, using the last supernova in the Large Magellanic Cloud (also a Type IIb event) as a guide, we calculate that when it does blow, Betelgeuse would shine at magnitude -10. That's 16 times fainter than a full moon, but 100 times brighter than Venus, making it easily visible in the daytime sky. A Betelgeuse-gone-supernova would also easily cast noticeable nighttime shadows.
Nearby supernova candidates out to 1,000 light-years. Credit: Dave Dickinson
But see the ongoing fading event for yourself. Betelgeuse is easy to find in December, rising to the east at dusk. In fact, northern hemisphere winter is the very best time for the star to blow, as it's roughly opposite to the sun, and would dominate the night sky. Summer would be the worst time, as it would tease us from beyond the far side with the sun in the daytime sky.
Betelgeuse, versus the stars of the Winter Hexagon with annotated magnitudes (note: this was taken prior to the current dimming event). Credit: Steve Brown.
What's next? Well, expect Betelgeuse to brighten again in early 2020… though if it rebounds into negative magnitude territory past Rigel and Sirius, well, then things could get really exciting.
For now though, we're in a wait-and-see-mode for any New Year's Eve fireworks from Betelgeuse. Such an occurrence would be bittersweet: We would be extraordinarily lucky to see Betelgeuse go supernova in our lifetime… but familiar Orion the Hunter would never look the same again.
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On Earth and in space, NASA had a busy decade in the 2010s.
In its human spaceflight program, the agency retired the space shuttle and is now close to launching humans to space again, this time on commercial crew vehicles. NASA also changed its long-term destination for humans a few times; currently the agency is targeting the moon and Mars.
Meanwhile, NASA robots flew through interstellar space, imaged thousands of planets and sent reams of scientific data back to researchers. Here are some of the agency's milestones over the last 10 years.
Meanwhile, the Deep Impact spacecraft flew by Comet Hartley, becoming the first spacecraft to visit two comets. The Spirit rover on Mars fell silent about six years past its initial 90-day expiration date. The scientists behind the orbital Mars Odyssey mission released a global map of the Red Planet based on eight years of data from the spacecraft, which is still operating today.
2011
The shuttle program made its final bow this year carrying cargo to the International Space Station. One of the last shuttle flights delivered a $2 billion astrophysics experiment called the Alpha Magnetic Spectrometer in May. (Astronauts have been conducting spacewalks in 2019 to repair that instrument, which studies dark matter.) Finally, in July, the space shuttle made its last flight, wrapping up 30 years of operations and 131 flights (including two fatal accidents, in 1986 and 2003).
From then on, NASA astronauts would fly to space aboard Russian Soyuz capsules; discussions about how many seats to buy, and how often, would dominate much of the 2010s. The Obama administration chose to retain the planned Orion spacecraft, originally envisioned for the now-defunct Constellation program, recruiting it for other planned deep-space missions, including to an asteroid around 2025 and Mars in the 2030s.
Meanwhile, because of the soaring cost and numerous launch delays of the James Webb Space Telescope, which was then slated to launch in 2018, NASA said that the instrument would need to pull money from other planned science missions. But the ongoing NASA/European Hubble Space Telescope mission discovered a previously unknown moon around Pluto, Kerberos. (When the same instrument found a second, Styx, in 2012, NASA personnel began to worry that these moons meant the New Horizons probe might run into unexpected debris during its flyby of the dwarf planet in 2015.)
The International Space Station entered a new era of cargo support when SpaceX's Dragon spacecraft made the first private flight to the space station. NASA began construction on the massive Space Launch System rocket to bring astronauts across the solar system. (That craft's first flight, originally expected in 2017, was delayed until at least 2021.
NASA survived 7 minutes of terror when the Curiosity rover safely landed on Mars in August, stepping up the agency's search for habitability on the Red Planet; within weeks of landing, the spacecraft had found an ancient streambed and evidence that water had flowed in the craft's landing area. Meanwhile, the Dawn probe bid goodbye to the large asteroid Vesta in September 2012, after characterizing the object's iron core and finding large craters on its surface.
So many gyroscopes failed on the Kepler space telescope, by now long past its prime planet-hunting mission, that NASA pioneered a new technique that used the pressure of the sun to hold the instrument stable. This allowed Kepler to continue work under an extended mission, known as K2.
In other mission milestones, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft launched for the Red Planet on Nov. 18. Meanwhile, NASA announced an Asteroid Redirect Mission to snag a boulder off an asteroid in order to begin testing planetary defense techniques. And NASA launched a Landsat satellite, which continued an Earth-observation program that has been running since the early 1970s.
NASA extended the space station's scheduled mission to 2024. NASA and Russia's Roscosmos space agency quibbled over their shared human spaceflight plans when a senior Russian official sarcastically suggested that NASA send astronauts to space by trampoline. However, the partnership continued with no delays to human spaceflight.
Meanwhile, the NASA/European Cassini mission found signs of 101 water geysers at the Saturn moon Enceladus. Scientists studying the activity wondered whether the plumes could represent the sort of activity that might power microbial life. MAVEN arrived at the Red Planet to study the loss of Martian atmosphere over time.
2015
NASA astronaut Scott Kelly and Russian cosmonaut Mikhail Kornienko began a nearly yearlong mission in space, the first such long-duration flight since the Mir space station missions of the 1990s. Two cargo ships in a row failed to reach the space station, sparking speculation about how long a crew could survive without more supplies, but a third flight arrived as expected.
Two mission arrivals made headlines. The New Horizons spacecraft flew by Pluto in July and revealed a surprisingly complex world of ancient lakes and large mountains, prompting more cries from the astronomical community to give Pluto its planethood status back. The Dawn spacecraft arrived at dwarf planet Ceres in March for several years of investigation, including figuring out the nature of mysterious bright spots visible en route. These turned out to be salts.
Astronauts began installing new docking ports for commercial crew vehicles to arrive at the International Space Station. Bigelow Aerospace launched an "inflatable room" to the space station for testing in April that was inflated in May and remains operational as of this writing. President Donald Trump was elected, and his first space priorities after assuming office in January 2017 included canceling the Obama administration's plans to send humans to visit an asteroid.
Meanwhile, on Mars, Curiosity's drill encountered problems that took about two years to address. NASA delayed the launch of the InSight mission to join Curiosity on the Red Planet after a seismometer vacuum leak forced engineers to pull the instrument for a fix. The agency toyed with the idea of canceling the mission, but a subsequent review identified InSight as a high priority for life-seeking missions, and it was rescheduled, launching in 2018.
NASA astronaut Peggy Whitson captured the U.S. record for most overall time in space, landing in September with a total tally of 665 days in orbit.
Meanwhile, the NASA/European Cassini spacecraft wrapped up 13 years of investigations at Saturn by conducting a "grand finale" series of sweeps through the planet's rings. Then, controllers deliberately threw the machine into the atmosphere of the planet, to protect icy, potentially habitable moons in the neighborhood from any possibility of contamination.
The Trump administration released its first space policy directive in December, ordering NASA to fly astronauts to the moon in 2028. The plans rely on NASA's massive Space Launch System, which was the subject of a report on development and funding issues conducted by NASA's Office of Inspector General.
Voyager 2, a spacecraft launched in 1977 to explore the outer planets, crossed out of the bubble surrounding our sun and into interstellar space, continuing to send back data about its environment.
Two venerable missions ended when they ran out of fuel: Dawn, which had been studying the dwarf planet Ceres, and the Kepler space telescope, which showed that exoplanets are common in our universe.
NASA is also working to send astronauts safely back to the moon in 2024, after Vice President Mike Pence announced a four-year acceleration of the previous deadline. However, critics say the new timeline might not be realistic. NASA also celebrated the 50th anniversary of the Apollo 11 moon landing on July 20, marking the occasion with numerous events.
In space, astronauts began tricky repairs on a dark-matter detector called the Alpha Magnetic Spectrometer. NASA classified the missions as the most difficult spacewalk work since the Hubble Space Telescope upgrade conducted in 2009. NASA astronauts also performed the first all-woman spacewalk, and the agency announced that crewmember Christina Koch would stay in space three extra months, putting her on track to make the second longest spaceflight in NASA history.
NASA and other government agencies began the year during what would become the longest-ever government shutdown, prompting agency concerns about the long-term effects on astronomy.
Also in January, the New Horizons spacecraft flew by Kuiper Belt asteroid 2014 MU69, making that space rock the most distant object ever explored. The object is now formally known as Arrokoth. The New Horizons team began considering yet another, more distant destination to visit later in its mission.
Mars was particularly prominent in the agency's year. The Opportunity mission formally ended in February after the rover stopped responding to commands in 2018, following a dust storm. The InSight lander deployed its instruments on Mars; its seismometer has sent home intriguing results even as the lander's heat probe struggles to dig into the Martian surface. NASA's Mars Reconnaissance Orbiter marked 60,000 laps of the Red Planet; the orbiter's observations have helped with spacecraft landings and for observing change (such as new craters) on the Martian surface. And the agency continued launch preparations for its most advanced Mars rover yet, called Mars 2020, to search out habitable environments.
NASA prepared to say goodbye to the Spitzer Space Telescope, which finished its last year of operations of observing the universe in infrared light. Meanwhile, the NASA Lunar Reconnaissance Orbiter celebrated 10 years at the moon, which included numerous observations of water ice and old spacecraft landing or crash sites. The Chandra X-Ray Observatory marked its 20th anniversary of observing the universe in X-ray wavelengths.
On the human spaceflight front, we celebrated the 50th anniversary of the moon landing while also asking serious questions about the feasibility of Artemis, NASA’s plan to return to the moon’s surface by 2024. This year will also be remembered as a dance of slow progress and setbacks for Boeing and SpaceX.
Beyond the U.S., Israel and India found both success and failure in reaching the moon with uncrewed missions—success in that much of the feat is in the journey, and failure in that both landers failed to reach the lunar surface intact (though India’s moon satellite is operational). Japan’s Hayabusa2 pointed tiny projectiles at an asteroid and shot it in order to recover samples from beneath the surface; it’s now on its way home from Ryugu. We said goodbye to the Mars Opportunity rover. And who can forget the downright bizarre milestones as well, like the first alleged crime committed in space and the headache of unlicensed tardigrades on the moon?
But the talk of 2019 has been a new kind of space race. Not the battle for supremacy among the major private companies (like those of billionaires Elon Musk, Jeff Bezos, and, to a lesser extent, Richard Branson) and other space-focused startups, but one around something much smaller, with potentially bigger implications: satellite constellations.
Established companies and startups alike are zeroing in on launching large networks of small satellites (generally considered anything under 500 kilograms—in comparison, the Hubble Space Telescope is more than 11,000 kilograms). These are poetically called constellations, and they join most other satellites and the International Space Station in low Earth orbit. These small satellites are cheaper, easier to manufacture, and less expensive to send to space than their larger counterparts. And by working in concert, they can collectively cover a much bigger portion of the Earth than standard satellites, making them perfect for goals such as blanketing the globe in affordable high-speed internet.
Providing low-cost, fast internet to hard-to-reach areas is a worthy goal. It would give people in rural areas and areas with poor infrastructure an affordable way to connect to the internet and participate in the digital economy—in the U.S., roughly 25 million people still don’t have access to broadband internet. And there’s real competition in this space (pun intended): SpaceX has already launched the first satellites of its Starlink constellation, with a proposed final number of 42,000. Earlier this year, Blue Origin announced its intention to create its own constellation for satellite internet (with more than 3,000 satellites), and OneWeb has already launched the first satellites in its endeavor (about 2,500).
These small satellites would be joining an already crowded orbital zone. As of March 2019, there were roughly 1,300 operating satellites in low Earth orbit, along with thousands of pieces of junk—nonworking satellites that haven’t been de-orbited, and other debris (including what might be an empty trash bag). The idea of sending up this many more satellites (which would effectively double the current operational number by the end of 2020) is a real cause for concern for many in the space community.
SpaceX has been a particular focal point for this discussion. That’s partly because its constellation is proposed to be so massive, but also because anything the company does makes headlines. “SpaceX is at the center of this debate because not only are they launching more quickly than other planned megaconstellations, they may launch more than 10 times more satellites in their Starlink constellation than their competitors,” said Laura Forczyk, founder of the space consulting firm Astralytical. Really, though, SpaceX is just the easiest target, bearing the brunt of criticism that is particularly intense because of a massive, systemic problem. “It’s the difference between dealing with a dripping faucet versus turning on the water,” Forczyk said.
The first-ever collision between two satellites occurred earlier this year, between a defunct Russian communications satellite and an operational U.S. one. It’s likely the first of many, considering how crowded it’s getting up there. SpaceX’s Starlink satellites have collision detection software onboard, but earlier this year a Starlink satellite almost collided with one from the European Space Agency in something of a game of chicken: Apparently the anti-collision features worked as expected, but SpaceX decided not to move the satellite, forcing the ESA to take action. “If a satellite collides with something bigger than a dime, it may be seriously damaged,” said Brian Weeden, space junk expert and director of program planning at the Secure World Foundation. “If it collides with something bigger than a baseball, it will likely be catastrophically destroyed into thousands of new pieces.”
The bottom line is that it’s getting crowded upthere.
This becomes even more complicated when satellites die and become pieces of space junk. SpaceX does have a plan for that: Placing these satellites in an even lower orbit means that once they are offline, the Earth’s gravity will slowly pull them back toward the surface, where they will almost completely burn up in the atmosphere after about five years. Every company planning on launching these types of satellites has a similar de-orbiting plan. But that doesn’t solve the sheer volume problem for when these satellites are operational (and no one knows what the environmental impacts will be of thousands of tiny satellites burning up in the atmosphere). The bottom line is that it’s getting crowded up there.
There’s another issue here as well. Starlink has had an immediate negative impact on Earth-based astronomy—and only a small fraction of the planned constellation has been launched. This particular constellation is much more reflective than expected. Forczyk acknowledged that astronomers regularly compensate for aircraft and satellites in their observations. But new satellite constellations have made the problem much worse. “With Starlink, astronomers are seeing many more streaks than they’re accustomed to, and they worry about a future flood of light streaks in their images,” she said. In the view below, you can see a shot of the night sky, with definite streaks shooting across it. These streaks are Starlink satellites.
SpaceX’s chief operating officer, Gwynne Shotwell, told reporters that the company is working on a fix for the issue: an anti-reflective coating that will make the satellites less bright in the night sky. There’s no guarantee that this fix will work, but Shotwell said, “We’re going to get it done.”
However, these problems weren’t impossible to foresee—astronomers were warning about Starlink’s impact on observation work well before the first satellites launched. And even if SpaceX and others wanted to proceed with their plans without care or caution, satellite launches are ostensibly regulated. Low Earth orbit is an international zone, after all.
Right now, that regulation happens at the national level (though countries do cooperate on issues such as radio frequency use). Governments are responsible for regulating the space activities of companies that operate and launch from within their borders. But that outdated scheme isn’t sophisticated enough to regulate what private spaceflight companies are actually doing in orbit—there are no specific regulations for either space debris or satellite constellations, which leaves corporations to regulate themselves. According to Weeden, there is consensus among experts that satellite licensing requirements need to change. Unfortunately, though, we aren’t quite sure how to deal with the problem. It’s fully baked into the system, not the result of political changes of mood, so until the space community and the organizations that regulate it figure it out, these problems will continue to pile up.
2019 will likely be remembered as the year we really began to understand the costs of unregulated innovation. Let 2020 be the year we tackle the problem head-on at the national and international levels. “The problem of space junk is more challenging, akin to the struggle we have to clean up junk here on Earth,” said Forczyk. “Future generations are counting on us to solve these problems on and around the planet.”
GREAT FALLS — We have received reports and several photos from people in northern Montana of strange lights in the sky.
People in Browning and Rocky Boy shared photos with KRTV on Wednesday evening that show a row of bright lights in the sky.
Based on similar reports in recent days in other media outlets and similarities in the photos, they are likely small satellites passing overhead that were launched recently by SpaceX.
Meteorologist John Belski of TV station WLKY reported on Monday
that SpaceX has launched two sets of satellites this year called Starlink. Each launching had 60 small satellites that eventually will orbit the earth at an altitude of over 300 miles.
And on Sunday, meteorologist Will Haenni of station WWMT posted
: "The bright dots in the sky are satellites, approximately 175 miles above the surface of the Earth. They appear bright due to their solar array reflecting sunlight back to the dark side of the globe."
On Monday, November 11th, SpaceX launched 60 Starlink satellites from Space Launch Complex 40 at Cape Canaveral Air Force Station, Florida. The SpaceX website
explains: "SpaceX is developing a low latency, broadband internet system to meet the needs of consumers across the globe. Enabled by a constellation of low Earth orbit satellites, Starlink will provide fast, reliable internet to populations with little or no connectivity, including those in rural communities and places where existing services are too expensive or unreliable."
If you saw a row of UFO like lights in the sky in IL, IA, MI (like this but spaced out), that was SpaceX Starlink Satellites! You'll be able to see them in the next few days, too! Check here for a map (and set the time back to see their track today) https://t.co/wtkU9xSFY9pic.twitter.com/cZ4UUvj5Zc
Scientists applied a set of algorithms to laser-ranging telescopes and succeeded in increasing accurate detection of the space litter in Earth’s orbit threatening spacecraft safety.
Chinese researchers have improved the accuracy in detecting space junk in earth’s orbit, providing a more effective way to plot safe routes for spacecraft maneuvers.
“The possibility of successfully navigating an asteroid field is approximately 3,720 to one!” exclaimed C-3PO as Han Solo directed the Millennium Falcon into an asteroid field in “Star Wars: The Empire Strikes Back.” Earth’s orbit is nowhere near as dangerous, but after more than half a century of space activity, collisions between jettisoned engines and disintegrated spacecraft have formed a planetary scrapheap that spacecraft need to evade.
Scientists have developed space junk identification systems, but it has proven tricky to pinpoint the swift, small specks of space litter. A unique set of algorithms for laser ranging telescopes, described in the Journal of Laser Applications, by AIP Publishing, has significantly improving the success rate of space debris detection.
“After improving the pointing accuracy of the telescope through a neural network, space debris with a cross sectional area of 1 meter squared and a distance of 1,500 kilometers can be detected,” said Tianming Ma, from the Chinese Academy of Surveying and Mapping, Beijing and Liaoning Technical University, Fuxin.
Laser ranging technology uses laser reflection from objects to measure their distance. But the echo signal reflected from the surface of space debris is very weak, reducing the accuracy. Previous methods improved laser ranging pinpointing of debris but only to a 1-kilometer level.
Application of neural networks — algorithms modeled on the human brain’s sensory inputs, processing and output levels — to laser ranging technologies has been proposed previously. However, Ma’s study is the first time a neural network has significantly improved the pointing accuracy of a laser-ranging telescope.
Ma and colleagues trained a back propagation neural network to recognize space debris using two correcting algorithms. The Genetic Algorithm and Levenberg-Marquardt optimized the neural network’s thresholds for recognition of space debris, ensuring the network wasn’t too sensitive and could be trained on localized areas of space. The team demonstrated the improved accuracy by testing against three traditional methods at the Beijing Fangshen laser range telescope station.
The observation data of 95 stars was used to solve the algorithm coefficients from each method, and the accuracy of detecting 22 other stars was assessed. The new pointing correction algorithms proved the most accurate, as well as easy to operate with good real-time performance.
Ma aims to further refine the method. “Obtaining the precise orbit of space debris can provide effective help for the safe operation of spacecraft in orbit.”
Reference: “Research on Pointing Correction Algorithm of Laser Ranging Telescope Oriented to Space Debris” by Tianming Ma, Chunmei Zhao and Zhengbin He, 24 December 2019, Journal of Laser Applications. DOI: 10.2351/1.5110748
The 10 Strangest Animal Stories of 2019 Livescience.com
https://news.google.com/__i/rss/rd/articles/CBMiQmh0dHBzOi8vd3d3LmxpdmVzY2llbmNlLmNvbS8xMC10aW1lcy1hbmltYWxzLWFjdGVkLXdlaXJkLTIwMTkuaHRtbNIBRmh0dHBzOi8vd3d3LmxpdmVzY2llbmNlLmNvbS9hbXAvMTAtdGltZXMtYW5pbWFscy1hY3RlZC13ZWlyZC0yMDE5Lmh0bWw?oc=5
Giant cavities in the X-ray emitting intracluster medium (shown in blue, as observed by NASA's Chandra X-ray Observatory) have been carved out by a black hole outburst. X-ray data are overlaid on top of optical data from the Hubble Space Telescope (in red/orange), where the central galaxy that is likely hosting the culprit supermassive black hole is also visible. Credit: Massachusetts Institute of Technology
Billions of years ago, in the center of a galaxy cluster far, far away (15 billion light-years, to be exact), a black hole spewed out jets of plasma. As the plasma rushed out of the black hole, it pushed away material, creating two large cavities 180 degrees from each other. In the same way you can calculate the energy of an asteroid impact by the size of its crater, Michael Calzadilla, a graduate student at the MIT Kavli Institute for Astrophysics and Space Research (MKI), used the size of these cavities to figure out the power of the black hole's outburst.
In a recent paper in the Astrophysical Journal Letters, Calzadilla and his coauthors describe the outburst in galaxy cluster SPT-CLJ0528-5300, or SPT-0528 for short. Combining the volume and pressure of the displaced gas with the age of the two cavities, they were able to calculate the total energy of the outburst. At greater than 1,054 joules of energy, a force equivalent to about 1,038 nuclear bombs, this is the most powerful outburst reported in a distant galaxy cluster. Coauthors of the paper include MKI research scientist Matthew Bayliss and assistant professor of physics Michael McDonald.
The universe is dotted with galaxy clusters, collections of hundreds and even thousands of galaxies that are permeated with hot gas and dark matter. At the center of each cluster is a black hole, which goes through periods of feeding, where it gobbles up plasma from the cluster, followed by periods of explosive outburst, where it shoots out jets of plasma once it has reached its fill. "This is an extreme case of the outburst phase," says Calzadilla of their observation of SPT-0528. Even though the outburst happened billions of years ago, before our solar system had even formed, it took around 6.7 billion years for light from the galaxy cluster to travel all the way to Chandra, NASA's X-ray emissions observatory that orbits Earth.
Because galaxy clusters are full of gas, early theories about them predicted that as the gas cooled, the clusters would see high rates of star formation, which need cool gas to form. However, these clusters are not as cool as predicted and, as such, weren't producing new stars at the expected rate. Something was preventing the gas from fully cooling. The culprits were supermassive black holes, whose outbursts of plasma keep the gas in galaxy clusters too warm for rapid star formation.
The recorded outburst in SPT-0528 has another peculiarity that sets it apart from other black hole outbursts. It's unnecessarily large. Astronomers think of the process of gas cooling and hot gas release from black holes as an equilibrium that keeps the temperature in the galaxy cluster—which hovers around 18 million degrees Fahrenheit—stable. "It's like a thermostat," says McDonald. The outburst in SPT-0528, however, is not at equilibrium.
According to Calzadilla, if you look at how much power is released as gas cools onto the black hole versus how much power is contained in the outburst, the outburst is vastly overdoing it. In McDonald's analogy, the outburst in SPT-0528 is a faulty thermostat. "It's as if you cooled the air by 2 degrees, and thermostat's response was to heat the room by 100 degrees," McDonald explains.
Earlier in 2019, McDonald and colleagues released a paper looking at a different galaxy cluster, one that displays a completely opposite behavior to that of SPT-0528. Instead of an unnecessarily violent outburst, the black hole in this cluster, dubbed Phoenix, isn't able to keep the gas from cooling. Unlike all the other known galaxy clusters, Phoenix is full of young star nurseries, which sets it apart from the majority of galaxy clusters.
"With these two galaxy clusters, we're really looking at the boundaries of what is possible at the two extremes," McDonald says of SPT-0528 and Phoenix. He and Calzadilla will also characterize the more normal galaxy clusters, in order to understand the evolution of galaxy clusters over cosmic time. To explore this, Calzadilla is characterizing 100 galaxy clusters.
The reason for characterizing such a large collection of galaxy clusters is because each telescope image is capturing the clusters at a specific moment in time, whereas their behaviors are happening over cosmic time. These clusters cover a range of distances and ages, allowing Calzadilla to investigate how the properties of clusters change over cosmic time. "These are timescales that are much bigger than a human timescale or what we can observe," explains Calzadilla.
The research is similar to that of a paleontologist trying to reconstruct the evolution of an animal from a sparse fossil record. But, instead of bones, Calzadilla is studying galaxy clusters, ranging from SPT-0528 with its violent plasma outburst on one end to Phoenix with its rapid cooling on the other. "You're looking at different snapshots in time," says Calzadilla. "If you build big enough samples of each of those snapshots, you can get a sense how a galaxy cluster evolves."
More information:
Michael S. Calzadilla et al. Discovery of a Powerful >1061 erg AGN Outburst in the Distant Galaxy Cluster SPT-CLJ0528-5300, The Astrophysical Journal (2019). DOI: 10.3847/2041-8213/ab5b07
This story is republished courtesy of MIT News (web.mit.edu/newsoffice/), a popular site that covers news about MIT research, innovation and teaching.
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Astronomers describe a violent black hole outburst that provides new insight into galaxy cluster evolution (2019, December 24)
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