Upsilon Andromedae d
Planet· orbits Upsilon Andromedae
Upsilon Andromedae d (Majriti) - the outer giant (~10 Jupiter masses) on a wide, eccentric 3.5-year orbit near the temperate zone. Its orbit is steeply tilted relative to planet c - a fossil of past upheaval. Never imaged.
Open in 3D viewSee Upsilon Andromedae d in the live, interactive 3D map
Key facts
Mass
1.95 × 10²⁸ kg
10.3 M♃ (3,258 M⊕)
Year
3.49 Earth years
1,276 Earth days
Distance from Upsilon Andromedae
2.51 AU
Science
Physical
- Mass
- 1.95 × 10²⁸ kg · 10.3 M♃ (3,258 M⊕)
- Radius
- Not measured
- No transit — radius is a model estimate; no density is quoted.
Orbital
- Semi-major axis
- 2.51 AU
- From the NASA Exoplanet Archive (radial-velocity orbit)
- Eccentricity
- 0.299
- From the NASA Exoplanet Archive (radial-velocity orbit)
- Inclination
- 0.00 °
- From the NASA Exoplanet Archive (radial-velocity orbit)
- Orbital period
- 3.49 years
- From the NASA Exoplanet Archive (radial-velocity orbit)
- Perihelion
- 1.76 AU
- Computed from the orbital elements
- Aphelion
- 3.26 AU
- Computed from the orbital elements
- Mean orbital velocity
- 21.4 km/s
- Computed from the orbital elements
Composition
- Bulk composition
- A gas giant of true (astrometric) mass ~10 Jupiter on an orbit steeply tilted to the inner planets — a fossil of past scattering. 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 Visual mode; Realism shows a plain spectral colour.
Radiation & temperature
- Insolation
- 0.53 S⊕ · 53% of the sunlight Earth receives
- Computed from Upsilon Andromedae's luminosity and the orbital distance (inverse-square; Earth's sunlight = 1).
- Equilibrium temperature
- 234 K (-39 °C)
- Computed model value for its 3.5-year orbit near the temperate zone — not measured.
Discovery & history
- Method
- Radial-velocity detection (stellar wobble)
- Name
- Designated 'd' 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').
Announced in 1999; later shown to orbit in a plane badly misaligned with the inner planets, evidence of planet-planet scattering.
Images
No official imagery available — this object has never been visited and no officially-licensed depiction exists.