Scientists have discovered the core of a giant gas planet. This is an unprecedented occurrence, which means we have a lot to learn since the interiors of these types of planets are poorly understood.
Planets like Jupiter and Saturn have a core, under their envelope of hydrogen and helium gas. However, until now, nobody has known what the cores look like.
Astronomers from the University of Warwick, published a study on Wednesday, 1 July, in the Journal Nature, detailing their observance of a planetary core.
The core, named TOI-849b, is about the same size as Neptune, and is believed to have been a gas giant which was either stripped of its gaseous atmosphere or that had not formed one at all. It was found circling a start about 730 light-years away.
First discovered by NASA’s Transiting Exoplanet Survey Satellite (TESS), the object was analysed in a program lead by the University of Warwick, using the HARPS instrument at the European Southern Observatory’s La Silla Observatory in Chile.
“While this is an unusually massive planet, it’s a long way from the most massive we know. But it is the most massive we know for its size, and extremely dense for something the size of Neptune, which tells us this planet has a very unusual history. The fact that it’s in a strange location for its mass also helps — we don’t see planets with this mass at these short orbital periods,” said Lead author Dr David Armstrong from the University of Warwick Department of Physics to Science Daily.
The planet orbits extremely close to its parent star. So close, that a year is only 18 hours and its surface temperature is approximately 1 527C, according to BBC News.
“TOI 849 b is the most massive terrestrial planet — that has an earth like density — discovered. We would expect a planet this massive to have accreted large quantities of hydrogen and helium when it formed, growing into something similar to Jupiter. The fact that we don’t see those gases lets us know this is an exposed planetary core. This is the first time that we’ve discovered an intact exposed core of a gas giant around a star,” said Armstrong.
Image: Twitter/Harald Schendera/© University of Warwick/Mark Garlick