The planetary core orbits very close to its parent star
Astronomers have found a previously unseen type of object circling a distant star.
It could be the core of a gas world like Jupiter, offering an unprecedented glimpse inside one of these giant planets.
Giant planets like Jupiter and Saturn have a solid planetary core beneath a thick envelope of hydrogen and helium gas.
But no-one has previously been able to see what these solid cores are like.
Now, a team of astronomers has discovered what they think are the rocky innards of a giant planet that’s missing its thick atmosphere. Their findings have been published in the journal Nature.
Lead author David Armstrong, from Warwick University, and colleagues had been running a programme to detect exposed planetary cores in data from the Tess space telescope.
“This was one of the candidates we picked out as something to try to observe,” he told BBC News.
“We followed it up with an instrument called the Harps spectrograph in Chile, which we used to measure the masses of these candidates. This one came out as being exceptionally massive – much more than we expected really. That’s when we started to look into what could have caused that.”
When the researchers first looked at the object, they thought it might be a binary star.
“We kept taking data and it turned out to still be a planet – just an exceptionally massive one for its size,” Dr Armstrong explained.
Its radius is about three-and-a-half times larger than Earth’s but the planet is around 39 times more massive.
The Tess spacecraft was launched in 2018