NASA (Exoplanet Catalog artwork)Kepler-37b
A planet barely bigger than our Moon
Overview
Kepler-37b is an exoplanet orbiting the star Kepler-37 in the constellation Lyra. As of February 2013, it is the smallest planet discovered around a main-sequence star, with a radius slightly greater than that of the Moon and slightly smaller than that of Mercury. The measurements do not constrain its mass, but masses above a few times that of the Moon give unphysically high densities.
Source: Wikipedia
NASA: Kepler-37 b is a terrestrial exoplanet that orbits a G-type star. Its mass is 0.79 Earths, it takes 13.4 days to complete one orbit of its star, and is 0.1019 AU from its star. Its discovery was announced in 2013.
Why it matters
- Announced in 2013 as the smallest planet around a main-sequence star.
- About 0.3 Earth radii, orbiting a Sun-like star every 13 days.
- Found thanks to asteroseismology, which pinned down the star's size precisely.
NASA puts it this way: “Kepler-37 b is a terrestrial exoplanet that orbits a G-type star. Its mass is 0.79 Earths, it takes 13.4 days to complete one orbit of its star, and is 0.1019 AU from its star. Its discovery was announced in 2013.”
Discovery & system
- Discovered
- 2013 · Transit · Kepler
- Discovery paper
- Barclay et al. 2013
- Discoverers
- Kepler Space Telescope
- Host star
- Kepler-37 · 5,357 K · 0.79 M☉
- System
- 4 known planets
- Siblings
- Kepler-37 c, Kepler-37 d, Kepler-37 e
The system
| World | Period | Distance | Radius | Mass | Temp. |
|---|---|---|---|---|---|
| Kepler-37 b | 13.4 d | 0.102 AU | 0.31 R⊕ | 0.79 M⊕ | 718 K |
| Kepler-37 c | 21.3 d | 0.139 AU | 0.76 R⊕ | 1.3 M⊕ | 615 K |
| Kepler-37 d | 39.8 d | 0.211 AU | 2.03 R⊕ | 2 M⊕ | 499 K |
| Kepler-37 e | 51.2 d | 0.25 AU | 0.37 R⊕ | ≥ 8.1 M⊕ | 401 K |
By the numbers
- Radius
- 0.31 R⊕1,974 km
- Mass
- 0.79 M⊕4.72 ×10²⁴ kg
- Orbital period
- 13.4 d0.04 yr
- Distance from star
- 0.102 AU15 million km
- Eccentricity
- 0.098elliptical
- Equilibrium temp.
- 718 K445 °C
- Starlight received
- 45 × Earth
- Distance from Earth
- 208 ly63.9 pc
- Density
- 140 g/cm³25.41 × Earth
Sources
Image: NASA (Exoplanet Catalog artwork) · NASA media: generally free of copyright · image page
Text: Wikipedia (CC BY-SA 4.0). Taglines and highlights are editorial.