Upsilon Andromedae b

Planet· orbits the Sun

Upsilon Andromedae b (Saffar) - a hot Jupiter (minimum mass ~0.7 Jupiter) skimming its star every 4.6 days. Found from the star's wobble, its mass is a minimum and it has never transited or been imaged.

Open in 3D viewSee Upsilon Andromedae b in the live, interactive 3D map

Key facts

Minimum mass
1.31 × 10²⁷ kg
0.688 M♃ (219 M⊕)
Year
4.62 Earth days
Distance from Upsilon Andromedae
8,856,194 km

Science

Physical

Minimum mass (m·sin i)
1.31 × 10²⁷ kg · 0.688 M♃ (219 M⊕)
Radius
Not measured

Orbital

Semi-major axis
8,856,194 km
Eccentricity
0.022
Inclination
0.00 °
Orbital period
4.6 days
Perihelion
8,661,358 km
Aphelion
9,051,030 km
Mean orbital velocity
139 km/s

Composition

Bulk composition
A hot gas giant (minimum mass ~0.7 Jupiter) of hydrogen and helium; among the first hot Jupiters found (1996). Never imaged.
Cloud appearance
Appearance based on ESO/M. Kornmesser's artist's concept. No spacecraft has imaged this world, so its real appearance is unknown — The banded clouds shown are a representation of its class, shown only in Vision mode; Realism shows a plain spectral colour.

Radiation & temperature

Insolation
956 S⊕ · 956× the sunlight Earth receives
Equilibrium temperature
1,524 K (1251 °C)

Discovery & history

Method
Radial-velocity detection (stellar wobble)
Name
Designated 'b' under the IAU convention that letters a star's planets 'b', 'c', 'd'... in the order they are discovered (the star itself is the unwritten 'a').

Discovered in 1996, among the first hot Jupiters found - the innermost of what became the first multi-planet main-sequence system.

Images

No official imagery available — this object has never been visited and no officially-licensed depiction exists.