Is Jupiter a failed star?

[lynyae]

I once saw a video of someone saying Jupiter is a failed star which also explains why its so massive. Is that true?

 

[Helio]

It’s hyperbole to grab attention, IMO.

As a protoplanet forming in a thick part of the early accretion disk, it grew quickly to a mass that allowed it to capture the great abundance of hydrogen. This is what the protosun was doing on or before this time.

But a star is the main collapsing part of the fragmented cloud. Planets are formed in the disks, though it’s common that other stars nearby will form, and are gravitationally attached.

There wasn’t likely enough mass in the disk to allow Jupiter to increase 25x in mass to become even a wimpy star.

This is also true, if one wishes to argue, that Earth is a failed star, but more so since it was too low in mass to hold hydrogen.