7.63
Apparent Mag159
Distance (ly)G0V
Spectral Type6,117
Temperature (K)HD 209458 hosts the first exoplanet discovered via the transit method. Its planet, known as Osiris, was the first to have its atmosphere detected.
Stellar Data
Apparent Magnitude7.63
Absolute Magnitude4.3
Distance159 light-years
Spectral TypeG0V
Temperature6,117 K
Luminosity1.61 L☉
Radius1.203 R☉
Mass1.148 M☉
Right Ascension22h 03m 10.8s
Declination+18° 53′ 03.5″
ConstellationPegasus
Notable Facts
- HD 209458 b (Osiris) was the first exoplanet found by the transit method
- It was the first exoplanet with a detected atmosphere
- The planet was found to be losing hydrogen from its atmosphere