TOI-521 b
A confirmed exoplanet orbiting TOI-521.
Compared with Earth
- Size
- About 2 times Earth's width.
- Mass
- About 5.3 times Earth's mass.
- Temperature
- About 521 °C (970 °F) from starlight alone, against -18 °C (-1 °F) for Earth measured the same way.
- Starlight
- About 66 times the starlight Earth gets from the Sun.
- Year
- A year here lasts about 1.5 Earth days.
Planet
- Radius
- 1.98 × Earth
- Mass
- 5.3 × Earth
- Density
- 3.8 g/cm³
- Equilibrium temperature
- 794 K
- Starlight received
- 66 × Earth
- Orbital period
- 1.543 days
- Average distance from its star
- 0.0195 AU
Star
- Host star
- TOI-521
- Spectral class
- M — red dwarf
- Surface temperature
- 3,544 K
- Radius
- 0.421 × Sun
- Mass
- 0.42 × Sun
- Age
- 0.8 billion years
System
- Distance from Earth
- 198.8 light-years (60.94 parsecs)
- Stars in system
- 1
- Known planets
- 1
Discovery
- Year
- 2025
- Method
- Transit
- Facility
- Transiting Exoplanet Survey Satellite (TESS)
Data from the NASA Exoplanet Archive, synced October 14, 2026.