TOI-1431b, also known as MASCARA-5b, was found 490 light-years from Earth. Nearly twice as large as Jupiter, the planet reaches temperatures that exceed the scorching red dwarf stars in our own Milky Way galaxy.
“This is a very hellish world - dayside temperature of … approximately 2700 degrees celcius and nightside temperature approaching … approximately 2300 degrees celcius – no life could survive in its atmosphere. In fact, the planet’s nightside temperature is the second hottest ever measured”, said Dr Brett Addison, a University of Southern Queensland astrophysicist, in a statement.
“It is a particularly interesting discovery as the host is one of the hottest stars with a transiting planet we’ve ever found, and because TOI-1431b is in such close orbit around its star, it’s one of the hottest planets surveyed.”
This temperature is significantly greater than the melting point of most metals, many of which will turn to liquid at under 2000 degrees celcius. Titanium melts at 1670 degrees, platinum at 1770 degrees, and stainless steel at between 1375 and 1530 degrees.
However, the world still does not manage to top the blistering temperatures of The Sun, which has a surface temperature of 5505 degrees.
These types of planets, known as ultra-hot Jupiters, are rarely discovered but this particular one is even more unusual due to its retrograde orbit.
“If you look at the Solar System, all the planets orbit in the same direction that the Sun rotates and they’re all along the same plane. This new planet’s orbit is tilted so much that it is actually going in the opposite direction to the rotation of its host star,” Dr Addison said.
TheTOI-1431b planet was first spotted by Nasa’s Transiting Exoplanet Survey Satellite (TESS), corroborated by observations and study from the Stellar Observation Network Group (SONG) telescope in the Canary Islands.