NASA (Exoplanet Catalog artwork)OGLE-2005-BLG-390Lb
'Hoth': the first cold super-Earth, found by a chance alignment of stars
Overview
OGLE-2005-BLG-390Lb is a super-Earth ice exoplanet orbiting OGLE-2005-BLG-390L, a star 21,500 ± 3,300 light-years from Earth near the center of the Milky Way, making it one of the most distant planets known. On January 25, 2006, Probing Lensing Anomalies NETwork/Robotic Telescope Network (PLANET/Robonet), Optical Gravitational Lensing Experiment (OGLE), and Microlensing Observations in Astrophysics (MOA) made a joint announcement of the discovery. The planet does not appear to meet conditions presumed necessary to support life.
Source: Wikipedia
NASA: OGLE-2005-BLG-390L b is a Neptune-like exoplanet that orbits a Unknown-type star. Its mass is 5.5 Earths, it takes 9 years to complete one orbit of its star, and is 2.6 AU from its star. Its discovery was announced in 2005.
Why it matters
- Detected in 2005 by gravitational microlensing — a one-off brightening that can never be repeated.
- About 5.5 Earth masses, orbiting a faint red dwarf near the galactic centre.
- With a surface near 50 K it was the coldest exoplanet known at the time.
NASA puts it this way: “OGLE-2005-BLG-390L b is a Neptune-like exoplanet that orbits an unknown-type star. Its mass is 5.5 Earths, it takes 9 years to complete one orbit of its star, and is 2.6 AU from its star. Its discovery was announced in 2005.”
Discovery & system
- Discovered
- 2005 · Microlensing · OGLE
- Discovery paper
- Beaulieu et al. 2006
- Discoverers
- Microlensing Observations in Astrophysics, Optical Gravitational Lensing Experiment
- Host star
- OGLE-2005-BLG-390L · 0.22 M☉
- System
- 1 known planet
The system
| World | Period | Distance | Radius | Mass | Temp. |
|---|---|---|---|---|---|
| OGLE-2005-BLG-390L b | 9 yr | 2.6 AU | 2.21 R⊕ | 5.5 M⊕ | 50 K |
By the numbers
- Radius
- 2.21 R⊕14,080 km
- Mass
- 5.5 M⊕32.85 ×10²⁴ kg
- Orbital period
- 9 yr
- Distance from star
- 2.6 AU389 million km
- Equilibrium temp.
- 50 K-223 °C
- Distance from Earth
- 21,526 ly6,600 pc
- Density
- 2.8 g/cm³0.51 × 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.