NASA (Exoplanet Catalog artwork)PSR B1620-26 b
also named MethuselahThe oldest known planet, almost as old as the Universe
Overview
PSR B1620-26 b is an exoplanet located approximately 12,400 light-years from Earth in the constellation of Scorpius. It bears the unofficial nicknames "Methuselah" and "the Genesis planet" due to its extreme age. The planet is in a circumbinary orbit around the two stars of PSR B1620-26 and is the first circumbinary planet ever confirmed. It is also the first planet found in a globular cluster. The planet is one of the oldest known extrasolar planets, believed to be about 12.7 billion years old.
Source: Wikipedia
NASA: PSR B1620-26 b is a gas giant exoplanet that orbits a Pulsar-type star. Its mass is 2.5 Jupiters, it takes 95 years to complete one orbit of its star, and is 23 AU from its star. Its discovery was announced in 2003.
Why it matters
- Estimated at about 12.7 billion years old, it orbits a pulsar and a white dwarf in the globular cluster M4.
- Roughly 2.5 Jupiter masses, circling the pair about once a century.
- Shows that planets could form in the metal-poor early Universe.
NASA puts it this way: “PSR B1620-26 b is a gas giant exoplanet that orbits an unknown-type star. Its mass is 2.5 Jupiters, it takes 95 years to complete one orbit of its star, and is 23.0 AU from its star. Its discovery was announced in 2003.”
Discovery & system
- Discovered
- 2003 · Pulsar Timing · Hubble Space Telescope
- Discovery paper
- Sigurdsson et al. 2003
- Discoverers
- S. E. Thorsett
- Host star
- PSR B1620-26 · 1.35 M☉
- System
- 1 known planet, 2 stars (circumbinary)
The system
| World | Period | Distance | Radius | Mass | Temp. |
|---|---|---|---|---|---|
| PSR B1620-26 b | 94.9 yr | 23 AU | 1.19 R♃ | 2.5 M♃ | — |
By the numbers
- Radius
- 1.19 R♃13.3 R⊕
- Mass
- 2.5 M♃795 M⊕
- Orbital period
- 68 yr
- Distance from star
- 23 AU3,441 million km
- Eccentricity
- 0.13elliptical
- Distance from Earth
- 5,871 ly1,800 pc
- Density
- 1.86 g/cm³0.34 × 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.