Finding Earth 2.0
HD 21520

HD 21520 b

Rank #1509 of the ranked catalogue · Discovered by Transit in 2024

HZ 0%upper limit

0.100

Earth-2.0 index

0.414

Earth Similarity Index

0%

Habitable-zone probability

2.70 R⊕

Radius

Planet

Mass17.700 M⊕upper limit
Bulk density1.350 g/cm³
Orbital period25.1292 days
Semi-major axis0.17260 au
Eccentricity0.000
Incident flux25.743 S⊕
Equilibrium temperature572.6 K
Transit-time σ at 203017.2 minLinear propagation of published epoch and period errors; not a ranking input.
Maximum angular separation2.18 masReflected-light contrast 4.24e-8 at Aᵍ = 0.30 and Lambertian quadrature.
Composite parameter sources3 · mixedThe archive may select different publications for different parameters; mixed-source is disclosed, not automatically penalised.
Default-solution coverage92%0% median composite-to-default difference over shared parameters.

Host star & system

HostHD 21520
Spectral typeG
Effective temperature5871 K
Radius1.044 R☉
Mass1.090 M☉
Distance79.2 pc / 258.3 ly
DiscoveryTransit, 2024