NASA ’s Transitioning Exoplanet Survey Satellite , TESS , has discover a dense and gaseous world locate around a dwarf star 53 light - years away . This is the third exoplanet discovered by TESS since its launch last year and the one with the foresightful orbital period . The determination was presented at the American Astronomical Society meeting , which is taking property in Seattle this week .
The new major planet is call HD 21749b and orbits a nearby dwarf whizz . It is classify as a U-boat - Neptune . It is three times the size of Earth but has a mass 23 times that of our planet . Its dimensions hint that the planet is most in all probability gaseous with a thicker and warmer atmosphere than Neptune or Uranus .
It has a aerofoil temperature of 148 ° C ( 300 ° farad ) , which is astonishingly low for a planet orbiting so nigh to its star . Its year lasts just 36 daytime and give that its star is almost as smart as the Sun , the whole satellite is very challenging .
“ It ’s the coolest small satellite that we love of around a star this bright , ” confidential information discoverer Dr Diana Dragomir , a postdoc at MIT ’s Kavli Institute for Astrophysics and Space Research , said in astatement . “ We know a lot about ambiance of hot planet , but because it ’s very hard to find small satellite that orbit farther from their stars , and are therefore cool , we have n’t been able to learn much about these smaller , cooler planet . But here we were golden , and hitch this one , and can now study it in more detail . ”
“ We think this major planet would n’t be as gaseous as Neptune or Uranus , which are mostly H and really puffy , ” Dragomir added . “ The planet in all likelihood has a denseness of water , or a boneheaded atmosphere . ”
TESS James Henry Leigh Hunt for exoplanets using the transition method , which call for looking for change in brightness . It is studying the brightness level of 200,000 superstar to spot change triggered by potential planets passing in front of them . It is the same approach used by the now - defunctKepler scope , but it will cover four times the area . Researchers hope to also discover more ground - like cool exoplanets .
During its two - year primary mission , researchers expect to incur more than 20,000 exoplanets , over five metre the number of exoplanets presently known . Among those , they estimate that 50 planets will be land or crack - Earth size and efflorescence for follow - up studies .
“ We ’ve confirmed three planet so far , and there are so many more that are just waiting for telescope and people clock time to be confirmed , ” Dragomir enounce . “ So it ’s go really well , and TESS is already assist us to learn about the diversity of these small planets . ”
The inquiry is submitted for publication in theAstrophysical Journal Letters .
