alt Hacker NewsWorth noting that the artist's impression is... not accurate. Both CD-35 2722 b (the brown dwarf orbiting the primary star) and CD-35 2722 b I (the exomoon orbiting the secondary) should be much closer in size. It is estimated that Jupiter is essentially the largest any gas giant can get; adding more mass will simply increase density and interior temperature until deuterium and lithium fusion and brown dwarfdom, and then at around 80 Jupiter masses, protium fusion and stardom.
Look at Barnard's Star[1], which is actually a fusing red dwarf star: it is not much bigger than Jupiter.
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they are close in size
it's just that one is farther away from the camera
One thing this implies is that the escape velocity of such objects increases linearly with mass, so the surface temperature they can sustain without losing mass increases quadratically with their mass. Massive super-jovian planets can orbit close to their star, limited only by tidal disruption. Some could even orbit within the outer envelope of the star for quite some time.
I kind of assumed the artist’s impression was working with perspective? The images shown in the sidebar seem to picture them at different relative sizes.
If a brown dwarf is right on the edge of stardom would it start protium fusion in only the part of itself that is the right pressure and then slowly burn out or would that ignition precipitate a pressure wave through the entire body forcing fusion to begin everywhere?
Nice charts in this paper that support this thesis
NASA exoplanet catalog has a neat system/star view
> It is estimated that Jupiter is essentially the largest any gas giant can get
That does not appear to be the case if we mean mass, not diameter.
It’s a perspective rendering, not orthographic. I don’t think you can reliably judge relative volume based on this image.