HN Peg b: Photographed, Not Inferred
Gas giant around HN Peg
It is 1.05 times Jupiter's radius, closest in size to Jupiter, and 6991.6 times Earth's mass.
Radius
11.78 Earth radii
Mass
6991.6 Earth masses
Orbit radius
773.0000 AU
Distance
59 light-years
Known and unknown, as the archive has it
A radius from transit photometry. Yes.
A weight, not just a width. Yes.
A density, so rock and gas can be told apart. No.
An orbital distance. Yes.
A temperature someone observed rather than calculated. No.
An eccentricity, so the orbit shape is known. No.
What seeing it actually provides
A position, a brightness, and light that can be split into a spectrum.
Found by Spitzer Space Telescope in 2006.
This is one of the rare planets that has actually been photographed. Fewer than a hundred of the thousands known were found this way, and they are mostly young giants far from their stars.
Fewer than a hundred planets have been photographed rather than inferred. Does \
seeing one directly change how real it feels to you?
