Gliese 581
GJ 581 · HIP 74995 · 6.22 pc · M3V · M dwarf with multiple planets
Section 01
General Information
Gliese 581 is an M3V red dwarf — the only M dwarf in the current Codex target list. Its inclusion tests whether the ATLAS9/HARPS pipeline extends to cooler stars and probes whether M dwarfs show different CHNOPS ratios than FGK dwarfs. Gl 581 e was one of the least massive exoplanets known at discovery (Mayor et al. 2009).
Stellar Parameters
| Parameter | Symbol | Value | Source |
|---|---|---|---|
| Effective temperature | Teff | ~3480 K | Literature |
| Surface gravity | log g | ~4.92 | Literature |
| Metallicity | [Fe/H] | ~−0.10 dex | Literature |
| Mass | M★ | ~0.31 M☉ | Literature |
| Spectral type | — | M3V | Red dwarf |
| Distance | d | 6.22 pc (20.3 ly) | Gaia DR3 |
Known Planets
| Planet | Mass | Type | Semi-major axis | Hab zone |
|---|---|---|---|---|
| GJ 581 e | 1.94 M⊕ | Super-Earth | 0.0285 AU | No — too hot |
| GJ 581 b | 15.65 M⊕ | Hot Neptune | 0.0406 AU | No |
| GJ 581 c | 5.57 M⊕ | Super-Earth | 0.0721 AU | Inner edge marginal |
Section 02
NASA Interactive Visualization
Section 04
Our Findings
Section 05
References & Credits
Key Literature
Mayor et al. (2009), A&A 507, 487 — Gl 581 e discovery
Udry et al. (2007) — habitable zone planets (disputed)
Robertson et al. (2014) — activity-induced signals
Data Sources
NASA/IPAC Exoplanet Archive
SIMBAD / CDS — stellar parameters
Hipparcos / Gaia — parallax & distance
Image Credits
Credit: ESO — Artist concept of the Gliese 581 system
Interactive sky: CDS Aladin Lite v3 / DSS2
NASA Eyes: NASA/JPL-Caltech
Pipeline
HARPS S1D — ESO Science Archive
Analysis: The Exoplanet Codex