Astronomers have found a frozen exoplanet more than three times the earth's mass and circle a star that is only…
Astronomers have found a frozen exoplanet more than three times the earth’s mass and circle a star that is only six light years away. The Exoplanet circles Barnard’s star, the closest solitary star to our sun.
This makes it the second best known exoplanet for us. Previously, an exoplanet was found in the three-star Proxima Centauri system.
The exoplanet was found to have a total of 20 years of data, including 771 individual measurements, from seven instruments. The analysis that led to the discovery is detailed in a study published Wednesday in the journal Nature.
Over the years, astronomers thought they would find a planet around the nearby the star, but it disappeared.
“The biggest” fired “about this discovery is the host star,” Paul Butler, co-author and astronomer at Carnegie Department of Science, wrote in an email. “Barnard’s star is” the great whale of the hunt. “
The planet, known as Barnard’s star b, is probably slightly illuminated by its star and a little colder than Saturn. The scientists believe it is a fiery desert without floating water, a hostile environment there The average surface temperature is around minus -274 degrees Fahrenheit.
However, the red dwarf star emits only about 0.4% of our solar radiation so that the planet receives about 2% of the intensity the Earth receives from its sun. that Barnard’s star is in the class M dwarf stars, colder and less massive than our sun. It is also an old star that precedes our own solar system.
And to watch it through a telescope, the star seems to be the fastest among the others the stars on the night sky. It’s because it’s moving fast to the sun, and it’s almost a single star in heaven for us, Butler says.
“The star is called for to honor the great American astronomer Edward Emerson Barnard, who was a pioneer of star photography and astrometry, “said Butler. “He acknowledged that this star had the greatest known movement a century ago.”
The planet is about the same orbital distance from its star as mercury is from our sun and makes a full passage around the star every 233 days. This places it in the star’s “snow line”, where it is cold enough for water to freeze to solid ice. This region of a planet system is where the building blocks of planets are considered to form, collecting materials to become cores. As they move closer to their host stars, more material accumulates, they become planets.
This is the first time a planet that is small and distant from its star has been detected using the radial velocity technique, which Butler helped with the pioneer. This method is sensitive to the mass of the exoplanet and measures changes in the host star’s speed. Instruments can be used to detect small wobbles in the star’s path caused by the earth’s gravity.
“I think this discovery shows the power of the [radial velocity] technology to detect longer periods, small planets that are much more difficult or impossible to detect with missions like Kepler and TESS, focusing on finding transoplanets for shorter periods,” wrote Johanna Teske, co-authors and Hubble Fellow at Carnegie Institution for Science, in an email. “This study provides a wonderful example of collaboration and coordination between multiple groups and multiple data sets, something that does not always happen successfully in exoplanet research. It’s only by combining data and working together that this very challenging detection was possible.”
These methods have not always been available to astronauts looking for exoplanets. Over the last hundred years, the only way that the astrometric technology, where astronomers are looking for the host star to angle relative to background stars, was Butler. It only worked for the nearest stars and was achieved by taking pictures of the star and measuring their positions in relation to each other.
“This made Barnard’s star the most important star in heaven because it is closest to the single star in heaven,” Butler said.
During the 1930s, the Dutch-American astronomer Peter van de Kamp began to study Barnard’s star that lasted for most 93 years. His claims about how the planets could fit in the orbit around the star was disproved, and he died five months before the first verifiable discovery of an exoplanet was made in May 1995, Butler said.
“He worked hard to improve the only technology at the time that had a prayer to find planets, and spent decades collecting data,” Butler said. “Van de Kamp is a true pioneer in extrasolar planets.”  Due to its proximity to our solar system and its long circulation, future missions and telescopes will be able to provide new insights into Barnard’s star b.
“Future space-based telescopes like WFIRST can observe reflected light from Barnard’s star outside the planet and thus tell us something about the composition of the surface and / or atmosphere on the planet, “said Teske.