The 47 UMa System

3 planets 1 in habitable zone Ursa Major

47 UMa is a planetary system in the constellation Ursa Major hosting 3 confirmed exoplanets, about 45 light-years from Earth. One of its planets orbits within the habitable zone, where liquid water could exist on a planetary surface.

47 UMa: Star and Habitable Zone

47 UMa

Surface temperature: 5,872 K (Sun: 5,772 K)
Mass: 1.06 M☉
Radius: 1.21 R☉
Luminosity: 1.5769 L☉

47 UMa b 47 UMa c → 47 UMa d →

Too hot Optimistic habitable zone Conservative habitable zone Too cold

Habitable zone of 47 UMa: 0.937–2.202 AU (conservative: 1.187–2.088 AU), per Kopparapu et al. (2014). Earth orbits the Sun at 1 AU.

See the full interactive habitable-zone view in the Exoplanet Explorer app ›

All 3 Planets in the 47 UMa System

Planet	Type	Orbit	Radius	ESI	Discovered
47 UMa b HZ	Cold Gas Giant	1,078 d	—	0.31	1996
47 UMa c	Cold Gas Giant	2,391 d	—	0.17	2001
47 UMa d	Cold Gas Giant	14,002 d	—	0.08	2009

Discovery History

The first planet found here, 47 UMa b, was discovered in 1996 using the radial velocity method. The most recent addition, 47 UMa d, followed in 2009.

1996 — 47 UMa b (Radial Velocity)
2001 — 47 UMa c (Radial Velocity)
2009 — 47 UMa d (Radial Velocity)

Frequently Asked Questions About 47 UMa

How many planets does 47 UMa have?

47 UMa has 3 confirmed exoplanets. More may await discovery.

Are any planets in the 47 UMa system habitable?

One planet in the system orbits within the habitable zone, where liquid water could exist. Actual habitability depends on atmospheres and composition, which are not yet known.

How far away is 47 UMa?

47 UMa is about 45 light-years from Earth in the constellation Ursa Major.

Explore the 47 UMa system in the app

Browse, filter and compare 6,000+ exoplanets on iPhone, iPad and Apple Watch — with habitable-zone views, widgets and offline data.