Tag: exoplanets

Google Discovers New Planet Which Proves Solar System Is Not Unique

The Kepler-90 star system has eight planets, like our own

Google has previously discovered lost tribes, missing ships and even a forgotten forest. But now it has also found two entire planets.

The technology giant used one its algorithms to sift through thousands of signals sent back to Earth by Nasa’s Kepler space telescope.

One of the new planets was found hiding in the Kepler-90 star system, which is around 2,200 light years away from Earth.

The discovery is important because it takes the number of planets in the star system up to eight, the same as our own Solar System. It is the first time that any system has been found to have as many planets ours.

Andrew Vanderburg, astronomer and Nasa Sagan Postdoctoral Fellow at The University of Texas, Austin, said: “The Kepler-90 star system is like a mini version of our solar system.

You have small planets inside and big planets outside, but everything is scrunched in much closer.

“There is a lot of unexplored real estate in Kepler-90 system and it would almost be surprising if there were not more planets in the system.”

The planet Kepler-90i, is a small rocky planet, which orbits so close to its star that the surface temperature is a ‘scorchingly hot’ 800F (426C). It orbits its own sun once every 14 days.

The Google team applied a neural network to scan weak signals discovered by the Kepler exoplanet-hunting telescope which had been missed by humans.

Kepler has already discovered more than 2,500 exoplanets and 1,000 more which are suspected.

The telescope spent four years scanning 150,000 stars looking for dips in their brightness which might suggest an orbiting planet was passing in front.

Although the observation mission ended in 2013, the spacecraft recorded so much data during its four year mission that scientists expect will be crunching the data for many years to come.

The new planet Kepler-90i is about 30 per cent larger than Earth and very hot.

Christopher Shallue, senior software engineer at Google AI in Mountain View, California, who made the discovery, said the algorithm was so simple that it only took two hours to train to spot exoplanets.

Test of the neural network correctly identified true planets and false positives 96 percent of the time. They have promised to release all of the code so that amateurs can train computers to hunt for their own exoplanets.

Machine learning will become increasingly important for keeping pace with all this data and will help us make more discoveries than ever before,” said Mr Shallue.

This is really exciting discovery and a successful proof of concept in using neural networks to find planets even in challenging situations where signals are very weak.

We plan to search all 150,000 stars, we hope using our technique we will be able to find lots of planets including planets like Earth.”

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Venus May Once Have Been Habitable, According To NASA

Venus – a hellish planet with an atmosphere of carbon dioxide, almost no water and temperatures of more than 460 degrees Celsius – may once have been habitable, according to Nasa scientists.

Researchers used climate models to calculate that Venus might have had a shallow ocean of liquid water and temperatures that could have allowed life to exist for up to two billion years of its early history.

The atmosphere is 90 times as thick as the air on Earth and scientists had thought this was largely caused by the difference between the two planets’ rate of spin.

A day on Venus lasts 117 Earth days because it spins on its axis at a much slower rate. But recent research showed that Venus could have had an atmosphere similar to the Earth’s today.

The first signs that Venus once had an ocean were discovered by NASA’s Pioneer mission in the 1980s.

Venus is closer to the sun than Earth and receives far more sunlight.

This caused the ocean to evaporate, water-vapour molecules were broken apart into hydrogen and oxygen by ultraviolet radiation and the hydrogen escaped to space.

With no water left on the surface, carbon dioxide built up in the atmosphere and led to a runaway greenhouse gas effect that created present searing heat.

A map of Venus’s surface based on imagery collected by Magellan, Pioneer Venus, and Venera 13 and 14 .

Michael Way, a researcher at Nasa’s Goddard Institute for Space Studies (GISS) in New York, said: “Many of the same tools we use to model climate change on Earth can be adapted to study climates on other planets, both past and present.

Colleague Anthony Del Genio added: “In the GISS model’s simulation, Venus’ slow spin exposes its dayside to the sun for almost two months at a time.

In a statement, Nasa said it was thought that Venus may have had more land than Earth. One of the factors they had to take into consideration was the ancient sun was up to 30 per cent dimmer.

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Any Aliens On Exoplanet Proxima B Likely Wiped Out Last Year

The chances that the nearest planet beyond our solar system might be habitable and perhaps even host quirky, telepathic aliens have dimmed significantly thanks to one day last year when the star Proxima Centauri shone exceptionally bright.

Astronomers observed a huge solar flare from the star just four light-years away that increased its brightness a thousandfold for about 10 seconds and probably showered nearby planet Proxima b with energetic particles.

The findings were published Monday in The Astrophysical Journal Letters.

March 24, 2017, was no ordinary day for Proxima Cen,” said Meredith MacGregor, an astronomer at the Carnegie Institution for Science, in a statement.

It’s likely that Proxima b was blasted by high-energy radiation during this flare.

That’s bad news for the prospects of life there. Any intelligent beings would have basically experienced the horrible ending of the 2009 Nicolas Cage science fiction flick “Knowing.”

It was already known the dwarf star was prone to outbursts of smaller, X-ray flares.

But if Proxima b has also been on the receiving end of major flares like the one MacGregor and her colleagues caught with Chile’s Atacama Large Millimeter/submillimeter Array (ALMA), it’s not going to be worth planning a vacation there any century soon.

Over the billions of years since Proxima b formed, flares like this one could have evaporated any atmosphere or ocean and sterilized the surface,” she said.

There is hope for the future habitability of Proxima b, though. Eventually, Proxima Centauri will calm down and begin to cool into a white dwarf that might be far more hospitable.

Unfortunately, that’s unlikely to happen for at least another 4 trillion years, or roughly 300 times the current age of the universe.

Stubborn old star.

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Google’s AI Found An Overlooked Exoplanet

NASA has discovered an eighth planet around a distant star, which means we’re no longer the largest solar system we know of.

The discovery was made thanks to some artificial intelligence help from Google, which found the planet by scouring previously overlooked “weak” signals in data captured by the Kepler Space Telescope.

The newly found planet is located in the solar system around Kepler-90, a star about 2,500 light-years away from Earth that was previously discovered in 2014.

The Kepler Space Telescope has been searching the galactic sky for exoplanets, or planets outside our own Solar System, since it launched in 2009.

In order to sift through all the data that it’s captured since that launch, scientists usually look at the strongest signals first.

And that process has worked well enough so far. NASA has confirmed 2,525 exoplanets in that time, a number that has changed our understanding of how common it is to find planets around the stars that make up our galaxy.

Recently, though, artificial intelligence has become a more prominent tool in astronomy.

Scientists, including ones who work on the Kepler data, have increasingly turned to machine learning to help sort through typically lower-priority data to see what they might have missed.

In the process, they found an overlooked planet that’s now named Kepler-90i.

But while we now know that Kepler-90 has the same number of orbiting planets as our Sun, the solar system is a poor candidate in the search for extraterrestrial life or at least, life as we know it.

Kepler-90 is about 20 percent bigger and 5 percent warmer than our Sun. And its eight planets dance around the star in much closer orbits than the ones in our own Solar System.

In fact, their orbits are so comparatively small that seven of Kepler-90’s eight planets would fit in between the Earth and the Sun.

The discovery of Kepler-90i, came after NASA let Google train its machine learning algorithms on 15,000 signals from potential planets in the Kepler database.

The scientists then took the trained system and set it to work on data from 670 stars that were already known to have multiple planets, as they considered those to be the most likely hiding places.

The newly discovered planet in Kepler-90, along with one other found in the Kepler-80 solar system announced today, are the first NASA was able to confirm from these new results from Google’s AI.

The inclusion of machine learning in this process shouldn’t scare humans whose livelihood revolves around discovering and studying exoplanets, according to Chris Shallue, a senior Google AI software engineer who worked on the project.

What we’ve developed here is a tool to help astronomers have more impact,” Shallue said on a conference call about the news.

It’s a way to increase the productivity of astronomers. It certainly won’t replace them at all.

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Detecting Magnetic Fields On Brown Dwarfs And Exoplanets

Mysterious objects called brown dwarfs are sometimes called “failed stars.

They are too small to fuse hydrogen in their cores, the way most stars do, but also too large to be classified as planets.

But a new study in the journal Nature suggests they succeed in creating powerful auroral displays, similar to the kind seen around the magnetic poles on Earth.

This is a whole new manifestation of magnetic activity for that kind of object,” said Leon Harding, a technologist at NASA’s Jet Propulsion Laboratory, Pasadena, California, and co-author on the study.

On Earth, auroras are created when charged particles from the solar wind enter our planet’s magnetosphere, a region where Earth’s magnetic field accelerates and sends them toward the poles.

There, they collide with atoms of gas in the atmosphere, resulting in a brilliant display of colors in the sky.

As the electrons spiral down toward the atmosphere, they produce radio emissions, and then when they hit the atmosphere, they excite hydrogen in a process that occurs at Earth and other planets,” said Gregg Hallinan, assistant professor of astronomy at the California Institute of Technology in Pasadena, who led the team.

We now know that this kind of auroral behavior is extending all the way from planets up to brown dwarfs.

Brown dwarfs are generally cool, dim objects, but their auroras are about a million times more powerful than auroras on Earth, and if we could somehow see them, they’d be about a million times brighter, Hallinan said.

Additionally, while green is the dominant color of earthly auroras, a vivid red color would stand out in a brown dwarf’s aurora because of the higher hydrogen content of the object’s atmosphere.

The foundation for this discovery began in the early 2000s, when astronomers began finding radio emissions from brown dwarfs.

This was surprising because brown dwarfs do not generate large flares and charged-particle emissions the way the sun and other kinds of stars do. The cause of these radio emissions was a big question.

Harding, working as part of Hallinan’s group while pursuing his doctoral studies, found that there was also periodic variability in the optical wavelength of light coming from brown dwarfs that pulse at radio frequencies.

He published these findings in the Astrophysical Journal.

Harding built an instrument called an optical high-speed photometer, which looks for changes in the light intensity of celestial objects, to examine this phenomenon.

In this new study, researchers examined brown dwarf LSRJ1835+3259, located about 20 light-years from Earth.

Scientists studied it using some of the world’s most powerful telescopes the National Radio Astronomy Observatory’s Very Large Array, Socorro, New Mexico, and the W.M. Keck Observatory’s telescopes in Hawaii in addition to the Hale Telescope at the Palomar Observatory in California.

Given that there’s no stellar wind to create an aurora on a brown dwarf, researchers are unsure what is generating it on LSRJ1835+3259.

An orbiting planet moving through the magnetosphere of the brown dwarf could be generating a current, but scientists will have to map the aurora to figure out its source.

The discovery reported in the July 30, 2015 issue of Nature could help scientists better understand how brown dwarfs generate magnetic fields.

Additionally, brown dwarfs will help scientists study exoplanets, planets outside our solar system, as the atmosphere of cool brown dwarfs is similar to what astronomers expect to find at many exoplanets.

It’s challenging to study the atmosphere of an exoplanet because there’s often a much brighter star nearby, whose light muddles observations. But we can look at the atmosphere of a brown dwarf without this difficulty,” Hallinan said.

Hallinan also hopes to measure the magnetic field of exoplanets using the newly built Owens Valley Long Wavelength Array, funded by Caltech, JPL, NASA and the National Science Foundation.

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Pass it on: New Scientist

Giant Ringed Planet Likely Cause Of Mysterious Stellar Eclipses

A giant gas planet – up to fifty times the mass of Jupiter, encircled by a ring of dust – is likely hurtling around a star more than a thousand light years away from Earth, according to new research by an international team of astronomers, led by the University of Warwick.

Hugh Osborn, a researcher from Warwick’s Astrophysics Group, has identified that the light from this rare young star is regularly blocked by a large object – and predicts that these eclipses are caused by the orbit of this as-yet undiscovered planet.

Using data from the Wide Angle Search for Planets (WASP) and Kilodegree Extremely Little Telescope (KELT), Osborn and fellow researchers from Harvard University, Vanderbilt University, and Leiden Observatory analysed fifteen years of the star’s activity.

They discovered that every two and a half years, the light from this distant star – PDS 110 in the Orion constellation, which is same temperature and slightly larger than our sun – is reduced to thirty percent for about two to three weeks. Two notable eclipses observed were in November 2008 and January 2011.

Assuming the dips in starlight are coming from an orbiting planet, the next eclipse is predicted to take place in September this year – and the star is bright enough that amateur astronomers all over the world will be able to witness it and gather new data. Only then will we be certain what is causing the mysterious eclipses.
giant ringed planet
“September’s will let us study the intricate structure around PDS 110 in detail for the first time, and hopefully prove that what we are seeing is a giant exoplanet and its moons in the process of formation,” comments Hugh Oborn.

The eclipses can also be used to discover the conditions for forming and their moons at an early time in the life of a star, providing a unique insight into forming processes that happened in our solar system.

The research, ‘Periodic Eclipses of the Young Star PDS 110 Discovered with WASP and KELT Photometry’, is due to be published in the Monthly Notices of the Royal Astronomical Society.

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