Finding Earth 2.0
HAT-P-21 · G3

HAT-P-21 b

Rank #4423 of the ranked catalogue · Discovered by Transit in 2010

HZ 0%measured

0.075

Earth-2.0 index

0.123

Earth Similarity Index

0%

Habitable-zone probability

12.44 R⊕

Radius

Planet

Mass1547.832 M⊕measured
Bulk density3.634 g/cm³
Orbital period4.1245 days
Semi-major axis0.05037 au
Eccentricity0.230
Incident flux459.542 S⊕
Equilibrium temperature1176.9 K
Transit-time σ at 203010.6 minLinear propagation of published epoch and period errors; not a ranking input.
Maximum angular separation0.18 masReflected-light contrast 1.06e-5 at Aᵍ = 0.30 and Lambertian quadrature.
Composite parameter sources5 · mixedThe archive may select different publications for different parameters; mixed-source is disclosed, not automatically penalised.
Default-solution coverage67%0% median composite-to-default difference over shared parameters.

Host star & system

HostHAT-P-21
Spectral typeG3
Effective temperature5588 K
Radius1.210 R☉
Mass1.240 M☉
Distance277.3 pc / 904.4 ly
DiscoveryTransit, 2010