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Author Topic: NEWS ON SPACE AND OUR PLANETARY SYSTEM  (Read 369926 times)
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Darja
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« Reply #1785 on: Sep 13, 2018, 04:31 AM »


NASA’s planet-hunting TESS satellite spies comet cruising through space

Mike Wehner
BGR
9/13/2018

NASA’s new TESS spacecraft — which stands for Transiting Exoplanet Survey Satellite, in case you were wondering — is all ready to get its scientific mission underway, but before its incredible power could be unleashed by researchers it had to be tested by its handlers at NASA. The satellite snapped a gorgeous image of a massive star field which NASA showed off back in May, but the latest test image is even more stunning.

To test the satellite’s ability to track the movement of an object while remaining stable, NASA decided to point it at a nearby comet. That object, called C/2018 N1, now appears in a series of images that look like something pulled straight out of an old sci-fi movie.

The comet, which is pretty obvious in the images, is speeding through space with its bright tail shift and changing directions due to the effects of the solar wind coming from the Sun. All the other objects you can see in the video are actually distant stars. Their shadowy appearance is due to image processing, according to NASA.

“These images were taken during a short period near the end of the mission’s commissioning phase, prior to the start of science operations,” NASA explains.” The movie presents just a small fraction of TESS’s active field of view. The team continues to fine-tune the spacecraft’s performance as it searches for distant worlds.”

Watch: https://www.youtube.com/watch?v=RnhKBdDanFw

TESS’s primary goal will be to sniff out distant exoplanets which have not yet been detected by other technology. It will attempt to do this by spotting the dips in brightness of distant stars as planets pass in front of them. That might sound like a simple observation that wouldn’t yield much usable information, but astronomers can tell a great deal about a planet based on how much light it blocks and what the light looks like as it shines around distant objects.

Science operations are just beginning for TESS, and the spacecraft will be doing work for a long while. We can’t wait to see what it finds
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Darja
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« Reply #1786 on: Sep 14, 2018, 04:21 AM »

SETI project uses AI to track down mysterious light source

BGR
9/14/2018

Last year, astronomers tasked with hunting alien signals identified 21 repeating light pulses emanating from a dwarf galaxy located 3 million-light years away. The source could be a fast-rotating neutron star — or it could be alien technology, perhaps meant to propel a space-sailing craft. Now, the researchers used artificial intelligence to pore through the dataset to discover 72 new fast radio bursts generated by the mysterious light source.

Fast radio bursts (FRBs) are bright pulses of radio emission mere milliseconds in duration. The signals acquired by the Green Bank Telescope in West Virginia and then initially analyzed through traditional methods by the Breakthrough Listen — a SETI project led by the University of California, Berkeley — lasted only an hour.

What sets the source in question — called FRB 121102 — apart from other on-off fast radio bursts is that the emitted bursts fired in a repeated pattern, alternating between periods of quiescence and frenzied activity.

Since the first readings made on August 26, 2017, the team of astronomers has devised a machine-learning algorithm that scoured through 400 terabytes of data recorded over a five-hour-long period.

The machine learning algorithm called a “convolutional neural network” is often employed by tech companies to display online search results or sort images. It found an additional 72 bursts not detected originally, bringing the total number of detected bursts from FRB 121102 to around 300 since it was initially discovered in 2012.

    “This work is exciting not just because it helps us understand the dynamic behavior of fast radio bursts in more detail, but also because of the promise it shows for using machine learning to detect signals missed by classical algorithms,” said Andrew Siemion, director of the Berkeley SETI Research Center and principal investigator for Breakthrough Listen, the initiative to find signs of intelligent life in the universe.

The mystery still lingers, though. We still don’t know much about FRBs or what produced this sequence, but the new readings help put some new constraints on the periodicity of the pulses generated by FRB 121102. It seems like the pulses are not fired all that regularly after all, at least not if the pattern is longer than 10 milliseconds. More observations might one day help scientists figure out what is driving these enigmatic light sources, the authors of the new study wrote in The Astrophysical Journal.

    “Whether or not FRBs themselves eventually turn out to be signatures of extraterrestrial technology, Breakthrough Listen is helping to push the frontiers of a new and rapidly growing area of our understanding of the Universe around us,” said UC Berkeley Ph.D. student Gerry Zhang.


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« Reply #1787 on: Sep 15, 2018, 05:10 AM »

SpaceX will send its first passenger around the moon aboard a Big Freaking Rocket

ZME
9/15/2018

SpaceX is set to send a private passenger on a flight around the moon. This journey will be made aboard the company’s upcoming Big Falcon Rocket (BFR), which is designed to take up to 100 people as far away as Mars.

Initially, the company announced it would send two passengers around the moon on a Falcon Heavy and that the flight ought to happen at the end of 2018. It’s not clear at this point whether the passenger is one of these two persons or someone new altogether, but one of Elon Musk’s tweets suggests the individual may be Japanese. The identity of the passenger will be live-streamed on Monday, September 17 at 9 PM ET, along with further details.

    SpaceX has signed the world’s first private passenger to fly around the Moon aboard our BFR launch vehicle—an important step toward enabling access for everyday people who dream of traveling to space. Find out who’s flying and why on Monday, September 17. pic.twitter.com/64z4rygYhk

    — SpaceX (@SpaceX) September 14, 2018

The rocket (BFR) and spacecraft (Big Falcon Spaceship — BFS) that will carry this lucky passenger around the moon was first presented by Musk last year at the International Astronautical Congress. Both the BFR and BFS are designed to be reusable and to land automatically, like the famous Falcon 9 has demonstrated numerous times in the past.

According to Musk’s initial plan, the 348-foot-tall (106-meter) BFR system is powered by 42 Raptor engines. It should be capable of carrying up to 100 people in a pressurized passenger space that’s larger than that of an Airbus A380 airplane. BFR consists of a 190-foot (58-meter) tall booster for its first stage, and a 157-foot (48-meter) tall spaceship that also doubles as a second stage.

Besides people, the launch system will be capable of ferrying cargo across the globe or to and from the International Space Station. A BFR flight could take a person from Los Angeles to New York in 25 minutes. Being capable of launching satellites, BFR will also become an important contributor to the company’s bottom line. Eventually, the BFR will make all other SpaceX vehicles obsolete.

Ultimately, Musk said that he would like to retire all of the company’s current rockets and spacecraft — Falcon 9, the Falcon Heavy, and the Dragon spacecraft — to make way for a fleet comprised solely of BFRs.

So, when will this amazing spaceflight take place? It’s anybody’s guess, really, considering SpaceX’s track record of shifting timetables. First and foremost, the BFR would have to be ready and it’s not at all clear when this will be the case. Remember that the Falcon Heavy was first unveiled in 2011 but wasn’t ready to launch before 2018. December 2022 marks the 50th anniversary of the last human mission to the Moon, Apollo 17. Perhaps this could be an interesting (and realistic) target for SpaceX’s lunar passenger spaceflight.


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« Reply #1788 on: Sep 17, 2018, 04:33 AM »

Hubble captures photo of massive nearby galaxy that is still growing

BGR
9/17/2018

For most of us, staring up at the night sky only lets us see the brightest nearby stars, and if you’re anywhere near a city you probably won’t see much else thanks to pesky light pollution. The powerful lens on the Hubble Space Telescope doesn’t have to worry about any of that, and NASA can take gorgeous photos like the one you see above whenever it feels like it.

What you’re seeing here is a nearby galaxy called NGC 6744. It’s not a particularly interesting name, but that doesn’t make the colossal galaxy any less awesome. It’s up to twice as wide as our own Milky Way, and according to NASA it’s still a very active place.

The galaxy is thought to be around 200,000 light years across, which is about twice as wide as the Milky Way. In terms of its shape, it resembles our home galaxy quite a bit, with long, curved spiral arms made up of countless stars, planets, and loose gasses and dust.

“NGC 6744 is similar to our home galaxy in more ways than one,” NASA explains in a new blog post. “Like the Milky Way, NGC 6744 has a prominent central region packed with old yellow stars. Moving away from the galactic core, one can see parts of the dusty spiral arms painted in shades of pink and blue; while the blue sites are full of young star clusters, the pink ones are regions of active star formation, indicating that the galaxy is still very lively.”

The photo was taken with Hubble’s WFC3, which stands for Wide Field Camera 3. The spacecraft is certainly getting up there in terms of age, having recently celebrated its 28th year in service after being launched back in 1990. It’s clear that the telescope has plenty of life left in it, and that’s a very good thing considering the mounting delays and absurd cost overruns of its sorta-successor, the James Webb Space Telescope.

The James Webb was supposed to be in space for a decade already but it hasn’t even gotten off the ground. Northrop Grumman, the contractor who has been consistently disappointing NASA and the US government while working on the project, has been messing up big time in its construction. The company, of course, refuses to absorb those costs and would rather pass the bill to NASA, which is already struggling for funding. Oh well, at least we have Hubble!

This image taken by the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 (WFC3) shows a beautiful spiral galaxy called NGC 6744. At first glance, it resembles our Milky Way albeit larger, measuring more than 200 000 light-years across compared to 100 000 light-year diameter for our home galaxy. NGC 6744 is similar to our home galaxy in more ways than one. Like the Milky Way, NGC 6744 has a prominent central region packed with old yellow stars. Moving away from the galactic core, one can see parts of the dusty spiral arms painted in shades of pink and blue; while the blue sites are full of young star clusters, the pink ones are regions of active star formation, indicating that the galaxy is still very lively. In 2005, a supernova, named 2005at, was discovered within NGC 6744, adding to the argument of this galaxy’s liveliness (not visible in this image). SN 2005at is a type Ic supernova, formed when a massive star collapses in itself and loses its hydrogen envelope.


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« Reply #1789 on: Sep 18, 2018, 04:16 AM »

It Is Possible Jupiter Could Support Life, Scientists Say

BGR
9/18/2018

A new factor has been added to the debate on whether or not living organisms could exist on Jupiter. You probably know Jupiter is a Jovian planet, a giant formed primarily out of gases. So how could alien life be able to exist in an environment where most of the phases of matter are absent? The answer is simply found in the element of water.

Within the rotating, turbulent Great Red Spot, perhaps Jupiter’s most distinguishable characteristic, are water clouds. Many of the other clouds in this enormous perpetual storm are comprised of ammonia and/or sulfur. Life theoretically cannot be sustained in water vapor alone; it thrives in liquid water. But according to some researchers, the fact alone that water exists in any form on the planet is a good first step.

The Great Red Spot is still a planetary feature which stumps much of the scientific community today. As it has been observed for the past century and a half, the Great Red Spot has been noticeably shrinking. The discovery of water clouds may lead to a deeper understanding of the planet’s past, including whether or not it might have sustained life, as well as weather-related information.

Some scientists have pondered the possibility that, due to the hydrogen and helium content in its atmosphere, Jupiter could be a diamond-producing “factory.” They have further speculated that these diamonds could enter into a liquid state and a rainfall of liquid diamonds would be in the Jovian’s weather forecast.

Likewise, the presence of water clouds means that water rain (a liquid) is not entirely impossible. Máté Ádámkovics, an astrophysicist at Clemson University in South Carolina, had this to say on the matter:

    “…where there’s the potential for liquid water, the possibility of life cannot be completely ruled out. So, though it appears very unlikely, life on Jupiter is not beyond the range of our imaginations.”

Scientists are acting accordingly, researching the part which water plays in the atmosphere and other natural systems on Jupiter. They remain skeptical but eager to follow up on the new discovery. They shall also strive to find out just how much water the planet really holds.

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« Reply #1790 on: Sep 19, 2018, 04:14 AM »

South Africa's MeerKAT telescope will help uncover next space frontier

MeerKAT, a 64-dish telescope, was inaugurated into the larger Square Kilometre Array instrument on Friday. When finished in the late 2020s, the network of telescopes will be able to scan the sky 10,000 times faster with 50 times the sensitivity of any other telescope.

CSM
9/19/2018   

Carnarvon, South Africa

A scientific mega-project to unlock cosmic conundrums from dark energy to detecting extraterrestrial life was given a boost on Friday, when the 64-dish MeerKAT radio telescope was inaugurated in the remote South African town of Carnarvon.

Built at a cost of 4.4 billion rand, MeerKAT will be incorporated into the complex Square Kilometre Array (SKA) instrument, which when fully operational in the late 2020s would be the world’s biggest and most powerful radio telescope.

Up to 3,000 dishes co-hosted in Africa and Australia will then be able to scan the sky 10,000 times faster with 50 times the sensitivity of any other telescope and produce images that exceed the resolution quality of the Hubble Space telescope, scientists said of SKA.

"MeerKAT will address some of the key science questions in modern astrophysics – how did galaxies form, how are they evolving, how did we come to be here ... and for those purposes MeerKAT is the best in the world," said Fernando Camilo, chief scientist at the South African Radio Astronomy Observatory which built and operates the telescope.

At an inauguration attended by government officials and foreign dignitaries, Mr. Camilo released new images taken by MeerKAT of the region surrounding the supermassive black hole at the center of the Milky Way galaxy, some 25,000 light years away.

"We didn’t expect to use our telescope so early in the game, it’s not even optimized, but to turn it to the center of the galaxy and obtain these stunning images, the best in the world, tells you you’ve done something right, better than right,” he told Reuters.

MeerKAT is a followup to the KAT 7 (Karoo Array Telescope), built in the vast semi-desert Karoo region north of Cape Town to demonstrate South Africa's ability to host the SKA. Its name is a play on words: in Afrikaans "meer" means "more," as in "more KAT," but it also refers to the small mammal native to the Karoo and famed for standing on its hind legs to view the world.

Besides groundbreaking astronomy research, MeerKAT is also pushing boundaries in big data and high-performance computing with the likes of IBM helping develop systems able to handle the dizzying amount of data fed from each individual antenna to supercomputers buried deep underground to limit radio interference.

The biggest radio telescope of its kind in the southern hemisphere, MeerKAT looks like a cluster of eggs when you first see it about an hour’s drive outside Carnarvon.

But up close, each sensitive dish is almost as high as a three story building, rotating on a fixed pedestal as it scans the sky. Chosen because of its remoteness, with hills providing an extra shield against radio interference, the project site is the main African base for hundreds of antennae that will eventually be placed as far as Kenya and Ghana.

"The first phase of SKA 1 in South Africa is to add 133 antennas to that [of MeerKAT]," said Rob Adam, an SKA international board member.

The expansion is expected to start next year, said Mr. Adam, with the first prototype dish built in China already on site about 280 miles north of Cape Town in the Northern Cape province. MeerKAT will operate independently before being incorporated into SKA 1 sometime around 2023, Adam said.


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« Reply #1791 on: Sep 20, 2018, 04:33 AM »

Volcanoes on dwarf planet ooze ice instead of molten lava

ZME
9/20/2018

The dwarf planet Ceres is the largest object in the asteroid belt between Mars and Jupiter. It’s also one of the most interesting cosmic bodies in the area, with studies showing it may have water-vapor plumes and even a subsurface ocean. Now, new research shows that the dwarf planet’s geology is even more fascinating than meets the eye. Apparently, volcanoes have been erupting on the surface of Ceres for the past billion years. But these aren’t your typical volcanoes — instead of explosively spewing lava, they gently ooze ice!

The ice volcanoes

Ceres, which stretches only 965 km (600 miles) across, was first spotted on Jan. 1, 1801 by Sicilian astronomer Giuseppe Piazzi.  At first, Ceres was called a planet, but as more asteroid belt members were discovered, the cosmic object was demoted to an asteroid status. Its status changed again in 2006 when it was promoted to a dwarf planet — a classification it shares with Pluto.

In 2015, NASA’s Dawn mission discovered a huge volcano on the surface of Ceres. Called Ahuna Mons, the volcano measures 19 km (12 miles) at its base and stands 4.8 km (3 miles) tall. All its features suggested that Ahuna Mons was a young volcano, no older than 200 million years. This was downright perplexing to scientists, seeing how Ceres is geologically dead. Volcanic activity in the inner solar system generally wanes over time as the interior of a body cools, as is the case on Venus, Mars, and Earth’s moon. Why would a 4.5-billion-year-old Ceres suddenly become volcanically active?

Ahuna Mons, of course, is not your typical volcano. It’s what scientists call a cryovolcano — a volcano that erupts icy material instead of molten lava. Cryovolcanism can be spotted elsewhere on the moons Enceladus, Europa, and Triton, and perhaps on many other worlds in the outer solar system. These eruptions are likely powered by the bodies’ internal heat and make for some of the best places to search for life beyond Earth because they expel material buried from potentially life-friendly reservoirs below the surface.

Now, a team of researchers led by Michael Sori of the University of Arizona found that Ahuna Mons is not alone. By studying topographic maps captured by Dawn, the researchers found 32 large domes measuring more than 6.2 miles in diameter, which they suspected may be volcanoes. They eventually settled on 22 domes that suggest cryovolcanic activity, all of them estimated to be less than a billion years old.

According to the researchers, it’s likely that Ceres has grown a new cryovolcano every 50 million years, on average. These findings help to explain some of the dwarf planet’s puzzling features, showing, for instance, that Ahuna Mons is not the only cryovolcanic construct on Ceres but rather one of many. The results also suggest that although Ceres has been continually cryovolcanic for the past billion years, the amount of eruptive activity is actually but a fraction of what geologists typically see on Earth (100,000 times less volume), much less even than has occurred on Mars and Venus.

In addition to being less productive, the volcanic eruptions on Ceres are also much tamer than those on Earth. Instead of violent eruptions of ash, plume, and lava, cryovolcanoes simply ooze out cryomagma — a salty mix of rocks, ice, and other volatiles such as ammonia — which freezes on the surface.

The causes themselves of cryovolcanic eruptions on Ceres are still a mystery but future research could come up with an explanation as more probes visit other bodies in the solar system.

Scientific reference: Cryovolcanic rates on Ceres revealed by topography, Nature Astronomy (2018). DOI: 10.1038/s41550-018-0574-1.


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« Reply #1792 on: Today at 04:43 AM »

How Kepler opened our eyes to the vastness of our galactic neighborhood

As NASA's newest planet hunter, TESS, launches into space, scientists reflect on its predecessor. The Kepler space telescope revealed complexities of the universe that were previously beyond imagination.

CSM
9/21/2018 

Thousands of tiny pinpricks of light fill a dark sky on a cloudless night. For thousands of years, people have looked up at that star-filled, mysterious expanse and wondered what – or who – is out there. Do worlds like our own orbit other stars? Is life a common occurrence in the cosmos? Or, are we alone in the universe?

With the launch of a new mechanical “planet hunter” scheduled for this week after a delay, NASA will take the next step toward answering those ancient questions. TESS – the Transiting Exoplanet Survey Satellite – will scan almost the entire sky over the next two years, identifying planets orbiting stars (called exoplanets) in our own stellar neighborhood that may hold clues into the evolution of solar systems, Earth-like planets, and life.

But TESS isn’t the first orbiting telescope to search for exoplanets. NASA’s Kepler space telescope paved the way.

Since it first launched in 2009, Kepler has discovered more than 2,600 exoplanets and counting – nearly three-quarters of all known exoplanets. That flood of data, and the surprises hidden in it, have revolutionized how we see alien worlds and set scientists on a path to answering some of philosophers’ oldest and deepest questions about our place in the universe.

“Kepler gave us a true view of what’s out there,” says Lisa Kaltenegger, director of the Carl Sagan Institute at Cornell University in Ithaca, N.Y., and a member of the TESS science team. And, she says, “Nature seems to make planets wherever she can.”

Exoplanets are a relatively new discovery. Although philosophers and scientists had hypothesized that they were out there, it wasn’t until the 1990s that astronomers confirmed the first exoplanet discoveries. Before Kepler launched, a little more than 300 exoplanets had been detected using ground-based telescopes, and each was cause for celebration and many scientific publications.

But Kepler changed all that.

“It’s almost hard to remember how little we knew in 2009 when Kepler launched,” says Jessie Dotson, an astrophysicist at NASA’s Ames Research Center in Moffett Field, Calif., and a Kepler mission scientist.

From the ground, scientists discovered mostly giant exoplanets, thought to be like Jupiter. But Kepler data confirmed scientists’ suspicions: there are systems like ours out there – and ones that are wildly different.

A hunter's sight

By design, Kepler is a planet hunter. The mission was planned so that the space telescope could look at hundreds of thousands of stars at once and establish a sense of just how common exoplanets can be. To do that, it had to fit as many stars in its view as possible. So Kepler set its sights on a distant patch of sky in our galaxy, collecting data on stars’ brightness.

Using what’s called the “transit method,” scientists comb through that data looking for a dip in starlight, suggesting that a planet may be passing between its star and Kepler, momentarily blocking some of the light. Kepler was set to observe for at least three years in order to detect planets in an Earth-like orbit or tighter at least three times, to eradicate other explanations.

Focusing on an Earth-like orbit would enable Kepler to discover planets that might be able to host life. That’s because all life as we know it (read: life on Earth) requires liquid water. Earth’s distance from the sun makes it not too hot and not too cold for liquid water to be stable on the planet’s surface. That places it squarely in a band around the sun referred to as the habitable zone, or the Goldilocks Zone.

Kepler set out to determine if exoplanets are abundant in our galaxy, and they sure are. Scientists now say that there are more planets than stars.

“We expected that,” says Sara Seager, an astrophysicist at the Massachusetts Institute of Technology in Cambridge, Mass., and deputy science director for the TESS mission. “Stars are born with disks of gas and dust. And just like those dust bunnies want to form in your living room, we think planets want to form out of that material.”

Still, Dr. Dotson says, “There’s a big difference between thinking something is possible and knowing it’s true.”

Stranger than (science) fiction

The most common planets in Kepler’s plentiful data were actually unfamiliar ones: planets between the size of Earth and Neptune. Sometimes described as “super Earths,” or “mini Neptunes,” these planets have no direct analogue in our solar system. Scientists also found that solar systems like ours are not the most common. Most planetary systems occur around the dim, reddish M-dwarf stars, not the yellowish G-type stars like our sun. These stars make up nearly three-quarters of the stars in our galaxy and are the main target for the TESS mission.

And some of Kepler’s discoveries defied imagination.

The mysterious “mini Neptunes” aren’t the only weird planets discovered in Kepler data. Scientists have found evidence of water worlds, hot Jupiters, lava worlds, and even circumbinary exoplanets, which, like the fictional planet Tatooine in “Star Wars,” orbit two stars.

“The diversity of planets is breathtaking,” Professor Kaltenegger says. “If we had just found planets like those in our solar system, it would’ve been nice, but kind of boring.”

Another astonishing exoplanet was spotted orbiting a white dwarf, the smoldering embers of an extremely old star near death. A closer look at the system revealed that the planet was being pulled apart and drawn into the dying star, illustrating one end of planetary evolution.

This discovery has the potential to expand where and how astrobiologists search for signs of life, too. “This told us that these have been around for a long time, and we shouldn’t think of things just in space, we should think about them in time, also,” says Elisa Quintana, an astrophysicist at NASA’s Goddard Space Flight Center who served as a Kepler mission scientist for a decade before joining the TESS mission as a support scientist.

“Maybe every system has a little slice of time where there’s life,” she adds.

Kepler has provided considerable data for astronomers to start to piece together models of planetary evolution. But, “like most great science missions,” Professor Seager says, “it created more questions than it answered.”

Hunting for habitability

Like Kepler, TESS is primarily a planet-finding mission, but the new space telescope will focus on identifying planets that may hold the answers. The satellite will scan almost the entire sky looking for planets close enough (within 300 light-years of Earth) and bright enough for future missions, like NASA’s James Webb Space Telescope, to investigate.

TESS’s eye will be largely on M-dwarf stars (those little reddish ones that are so plentiful, especially in our corner of the galaxy). As Kepler showed, those stars could host many Earth-like planets in that sweet spot for liquid water, which opens up new questions in the search for extraterrestrial life.

“It’s making me rethink what is meant by habitability,” Dotson says. “Now you start to ask the question, is liquid water enough for habitability?”

Kepler data has pushed scientists to think as expansively as possible, not limiting themselves to the models we know: our planet and our solar system.

“We have these four terrestrial planets, and these four giant planets, and a sunlike star,” Dr. Quintana says. But Kepler has shown that our system is by no means standard. “And what if actually the most common habitable planet is a circumbinary planet? We could imagine people on these circumbinary planets doing searches for life and only considering systems with multiple stars.”

Between Kepler, TESS, and other missions, scientists are amassing a growing catalogue of exoplanets for future generations of scientists to study and build upon.

Kepler laid the groundwork for TESS and other future missions, and it wasn’t easy. “Kepler basically plowed down everything in its way” to lead the way, Kaltenegger says. When the principal investigator, William Borucki, first proposed it in 1992, the Kepler mission was seen as too uncertain and risky. It took him five tries to finally get it approved in 2000.

And then, after four years of observation and exoplanet discoveries, the prime mission was brought to an abrupt halt in May 2013 by a mechanical failure. Two of the four reaction wheels that maintained the space telescope’s orientation broke, rendering Kepler ineffective as a planet hunter.

But scientists weren’t ready to be done with Kepler yet.

The scientific community quickly figured out that they could use the pressure of solar radiation to stabilize the telescope so that its field of view ran along the orbital plane of Earth, looking at a new section of sky every 83 or so days. NASA approved the second Kepler mission, dubbed K2, in 2014, and the exoplanet discoveries started flooding in again.

Now, the space telescope faces a certain death: it’s nearly out of fuel, and is expected to run out within the next few months. But that won’t mean the end of new Kepler-spotted exoplanets. It could take about a decade to sift through the treasure trove of data from both the Kepler and K2 missions, a process that will bring to light even more exoplanet discoveries.

Over the course of its two lifetimes, Kepler did more than accumulate vast amounts of scientific data. That data also changed our perspective of the universe – and our place in it.

As a graduate student in the 1990s, Dotson, who is now the K2 project scientist, remembers staring up at the night sky “and just being blown away by all those pinpricks of light. I was learning how they worked, and the scales of how far apart they all were, and all that. And I remember sitting there being blown away by that. But at the same time it felt very, very lonely, because it’s just so vast.”

“When I’m lucky enough to look at the night sky now,” she says, “I’m blown away from a different perspective. It no longer feels lonely; it now feels just like a whole realm of possibilities have opened up.”

Watch: https://www.youtube.com/watch?v=sGwCpmEvCmA


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