The Kepler Space Telescope ended its extremely successful planetary hunting mission last year, but continues to make discoveries in the grave. NASA's Transiting Exoplanet Survey Satellite (TESS) has since taken over the planetary hunter's banner, but it still has a long way to go before it is at the same level as Kepler. The gap between the probes has also just widened. A new analysis of Kepler's data revealed hundreds of potential new exoplanets.
Kepler launched a three-and-a-half year mission in 2009 to find distant worlds. NASA is used to missions operating long after their expected lifespan, but Kepler began to experience problems in 2012. The probe used the transit method to detect exoplanets. This meant that Kepler had to stay focused on the same area for long periods, but two of his four-wheelers were down by mid-2013.
NASA was able to restore Kepler's partial functionality in 2014 by stabilizing it with photons reflected from its solar panels. This "K2" mission produced more data and exoplanets, but much of this data is "confusing" and difficult to interpret. Enter, Ethan Kruse, from NASA's Goddard Space Flight Center. Kruse and his team have developed a new method for processing K2 data using QATS (Quasiperiodic Automated Transit Search) and extracting and removing EPIC variability for exoplanet science targets (EVEREST ). The processing reduces arcs and noisy curves in the K2 data. The result is many, many new exoplanet signals.
This is not the first analysis of K2 data, so all 818 planets detected in the study are not new. However, an impressive 374 signals have not yet been detected. Of these, 154 are so-called transiting planets. This means that they transform their stars from our point of view on the Earth, and that the Earth does the same with these planets. So there could be extraterrestrial astronomers doing a similar experiment, wondering if Earth supports life. The data points to worlds of varying sizes, from super-Earth to gaseous giants, and there are 87 multi-planet systems.
Currently, all objects listed in the new analysis are mere "candidate" exoplanets. Another team will have to go check each signal to confirm. In the future, astronomers may be able to use the long-delayed James Webb Space Telescope to take a closer look at some of these planetary systems. For the moment, most of the verification will take place in large ground observatories.
There are thousands of confirmed exoplanets in the cosmos, and many of them are members of solar systems very different from ours. While missions such as Kepler and Transiting Exoplanet Satellite Survey (TESS) have highlighted more distant worlds, astronomers have been surprised to see how many of them have what's known as "hot Jupiters." ". WASP-121b is the hottest of these gaseous giants in close orbit. Is it hot? It is so hot that heavy metals escape and propel themselves around the star.
WASP-121b made the headlines in 2017 when scientists used Hubble to characterize its stratosphere. It was a first for any exoplanet and it showed that the temperature of the planet increased with the altitude, just like the planets of our solar system. This is a hot Jupiter with 1.2 times the mass of Jupiter himself. It is about 900 light years away from the head of a slightly larger, warmer star than the sun, but it is so close that its year is only 30 Earth days.
Even by the standards of a Jupiter, WASP-121b is absolutely burning. At 4600 degrees Fahrenheit (2500 degrees Celsius), it's 10 times warmer than any other exoplanet ever discovered. Although it is a little more massive than Jupiter, its diameter is almost twice as big, because the intense heat released by the WASP-121 made it swell. Hubble's new observations show what this intense heat represents for the planet.
The downy outer layers of WASP-121b are less subject to gravity than the inner layers, so they fall away from the planet in orbit. In most gas giants – even hot Jupiters – this would be mostly hydrogen and helium. However, Hubble says WASP-121b loses heavy metals like magnesium and iron. Astronomers assume that incredible heat is enough to lift heavy metals from the lower layers of the atmosphere upward, where they can be lost in space.
WASP-121b is too far away to directly image the atmosphere or the trailing metal gases, but Hubble can track the planet as it passes in front of its host star. The changes of light allow them to determine what is happening in the atmosphere of the exoplanet by spectroscopy. The most interesting aspect of the new analysis is perhaps that the infernal heat influences the shape of the planet. So much of the atmosphere is moving away that the planet probably looks a bit like a football.
Scientists hope to learn more about this extreme planet in the future. The future James Webb Space Telescope should be able to characterize its atmosphere even more precisely.
The Kepler planet search satellite has long since disappeared, but NASA's Transiting Exoplanet Survey Satellite (TES) is just beginning. This satellite has spotted a few exoplanets at the beginning of his mission, and the last batch includes some extremely strange worlds with yet another super-Earth. The super-Earth is hot and the others are colder. However, they are not ice worlds like Neptune.
The three planets revolve around a star called TOI-270, located about 73 light-years away. The TOI-270 is about 40% smaller than the sun and a third cooler. Yet the smallest of the three planets (TOI 270b) orbits close enough to the star (every 3.4 terrestrial days) to be inhospitable to life as we know it. It has a surface temperature of 254 degrees Celsius (490 degrees Fahrenheit). It is only 25% larger than the Earth and has a mass 1.9 times higher. Scientists think it is a rocky object.
The other two planets are cold and they do not seem to have any analogues in our solar system. TOI 270 c and TOI 270 d are respectively 2.4 and 2.1 times larger than the Earth. They probably have a mass between five and seven times that of the Earth. These planets are in orbit closer to their star than the Earth does with the sun: 5.7 days for YOU 270 c and 11.4 days for YOU 270 d. However, the lower temperature of the TOI-270 means that they are much less extreme.
Most gaseous giants we detect in other solar systems are either hot Jupiters or ice giants like Neptune. TOI 270 c and TOI 270 c and TOI 270 d are fascinating because it's a happy medium between the two. The TOI 270 is hot, but not as hot as a hot Jupiter at 150 degrees Celsius (300 degrees Fahrenheit). The TOI 270 d is not really comfortable at 67 ° C, but it is potentially habitable for very robust life forms. Again, these are equilibrium temperatures, which are based only on the energy received from the star. The actual temperature could be higher or lower.
Astronomers consider the TOI-270 system as an ideal place to learn about the evolution of the planet. We do not have planets like YOU 270 c and YOU 270 d in our solar system, so they could have a lot to teach us. The most exciting thing about the TOI-270 is perhaps its position in the sky. He will be in the field of view of the James Webb Space Telescope for more than six months after its launch. Astronomers will be able to gather a huge amount of data on this distinct solar system, which could change the way we understand global development.
Humanity is far from being able to colonize with a single star, not to mention the galaxy of the Milky Way. NASA's Jet Propulsion Laboratory (JPL) has launched an exciting challenge for scientists around the world as part of the 10th Global Trajectory Optimization Competition (GTOC X). The teams had to develop a process to colonize the galaxy in the most efficient way possible. It could take a few million yearsbut the simulations show how we could do it.
The contest, by its very nature, is based on many assumptions. Although we have detected thousands of exoplanets, most of them are too big, too hot or too cold for life. We do not have the technology to locate most Earth-like planets. So there is no world we know how to colonize. Therefore, the contest used a collection of 100,000 hypothetical habitable star systems spread around the Milky Way, all of which are identified by their location and trajectory (called ephemeris) in the contest rules. JPL judged the bids based on the number of stars chosen by the team and the energy expended to do so.
All teams must adhere to the same rules. The contest begins in 10,000 years in what JPL calls "zero year". From that moment, teams have 10 million years simulated to launch their colonization efforts from Earth. Everyone must also use the same initial colonization fleet. They start with three motherships, each with 10 colonization modules able to colonize the star systems as the ship passes. The mothership can also make only three course changes at a total speed of 500 kilometers per second. The Earth can also launch two "fast ships" that travel three times faster but can only colonize one star. Each established star can launch up to three decollating ships with an intermediate speed and the ability to colonize another star.
There is no hyper-advanced chain drive technology here. They are generational ships that can take thousands of years to reach their destination. Most bids used fast ships to launch missions to the edge of the galaxy and work inside colonizing ships. Meanwhile, the mother ships headed for the denser stars near the Earth to release all their pods.
The winning solution came from the Chinese National Defense Technology University and the Xi & # 39; s Satellite Control Center. Second place went to Tsinghua Chinese University, and ESA's team of advanced designers (ACT) ranked third. ACT has also posted a video of its solution on YouTube (see above).
JPL discovered that it took about 90 million years for teams to occupy large tracts of the Milky Way. The universe is billions of years old, why other species have not already done it? That's what we call the Fermi paradox, and nobody knows the answer. Maybe the universe teems with life, but traveling between the stars is fundamentally unachievable. Alternatively, there may be few or no advanced civilizations in the universe. It is even possible that extraterrestrials have colonized most of the galaxy, but they are moving away from Earth for an unknown reason. Anyway, these simulations are an interesting piece of the puzzle.
Astronomers around the world were thrilled in 2016 when the European Southern Observatory announced the discovery of an exoplanet around Proxima Centauri, the closest star to the Earth. The Centauri system contains a few extra stars. Now the very large telescope (VLT) has gotten an upgrade that will help it sweep these other stars to find evidence of exoplanets.
Proxima Centauri is a red dwarf star located 4.2 light-years from Earth. Alpha Centauri consists of two larger stars located about 4.37 light-years from Earth. Centauri A is a little bigger and brighter than the sun, while Centauri B is smaller and colder. While the exoplanet around Proxima Centauri is in the "habitable zone of the star", the red dwarf is very different from ours. Many scientists believe that Proxima Centauri's radiation and solar flares make life impossible on Proxima Centauri. This might not be the case for planets that may exist around Alpha Centauri A and B.
The VLT, a network of four eight-meter telescopes in Chile, already had the ability to observe the universe in mid-infrared wavelengths. He joins the hunt for exoplanets with the addition of an instrument called NEAR (Near Earths in the AlphaCen region) which makes it much more sensitive.
The planets orbiting the stars are theoretically easier to find, but the light of the Centaurs A and B makes the light relatively weak of an invisible planet. NEAR is an infrared coronograph that filters the light of a star, leaving only light from other objects in a solar system. This differs from traditional methods of detecting exoplanets, which rely on the analysis of their gravitational effects on a star or on the obscuration of starlight as the planets pass in front of it. NEAR could capture real images of an exoplanet.
The European Southern Observatory, which operates the VLT, estimates that NEAR will be sensitive enough to detect a small rocky planet about twice the size of the Earth. Most of the exoplanets detected by astronomers are much larger, but Alpha Centauri is a great place to look for smaller ones because they are so close. The navigation will not be fluid until the end. Alpha Centauri is a binary system. We do not know how planetary systems operate around binary stars, or even their existence.
The NEAR system has completed its first campaign of observation earlier this month. Now, it is up to scientists to look at the data to see if they have found traces of exoplanets around the stars.
NASA's Kepler Space Telescope has put an end to its mission of tracking the planet, but the exoplanet transient telemetry satellite (TESS) has already taken up the torch. TESS has detected a new exoplanet called HD 21749c. This is not the first planet to appear in the TESS data, but is the first planet the size of the Earth.
TESS launched in April 2018 at the top of the Falcon 9 rocket. The Kepler telescope was already experiencing problems due to mechanical failures at that time, but it had already exceeded expectations by spotting thousands of potential exoplanets. TESS started its scientific activities in July 2018, several months before NASA announced that Kepler was out of fuel and was going to shut down. Since then, TESS has several exoplanets, including a "hot Jupiter" at 480 light-years and a super-Earth in orbit around Pi Mensae, 60 light-years away.
The newly identified exoplanet is 52 light-years away, gravitating around a star called HD 21749. There are actually two planets in this solar system (and maybe we do not have still discovered). HD 21749b is a large "sub-Neptune" planet with a 36-day orbit announced by researchers in January. The HD 21749c is about the size of the Earth and gravitates around the star in just 7.8 Earth days.
Although the HD 21749c is the size of the Earth, it is probably inhospitable to life as we know it. With its tight orbit, the surface temperature of the HD 21749c probably exceeds 426 degrees Celsius (800 degrees Fahrenheit). It is, however, an important step for TESS, with which NASA hopes to catalog at least 50 Earth-like planets during its two-year mission.
TESS has a set of four extremely sensitive cameras taking one picture every two seconds. Scientists then observe the repeated luminance variations of distant stars, indicating that planets are passing in front of them. This is an effective way to detect remote objects, but it only works on solar systems that are properly aligned with ours.
During its mission, TESS will scan the entire sky and send back data about 500,000 stars. The observed area will be about 400 times larger than Kepler, but TESS will not see the exoplanets as far. Scientists expect most detections to occur within 300 light-years. However, scientists will be able to collect more data on planets such as mass and atmospheric composition because of their relative proximity. To take a closer look, we will have to wait for the James Webb Space Telescope, which is currently scheduled for release in 2021.