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BD+15 2940 b

Cold Gas Giant Serpens

BD+15 2940 b is a cold gas giant orbiting the K0 star BD+15 2940 in the constellation Serpens. It lies about 1,391 light-years from Earth and was discovered in 2013 using the radial velocity method.

353×Earth mass
137 dOrbital period
0.07Earth similarity
1,391 lyDistance
2013Discovered

Is BD+15 2940 b in the Habitable Zone?

BD+15 2940 b orbits inside the inner edge of the habitable zone of BD+15 2940. So close to its star, surface conditions are far too hot for liquid water.

BD+15 2940 b
Too hot Optimistic habitable zone Conservative habitable zone Too cold

Habitable zone of BD+15 2940: 7.997–19.498 AU (conservative: 10.129–18.486 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 ›

Orbit and Year Length

A year on BD+15 2940 b — one full orbit around BD+15 2940 — lasts 137.5 Earth days, between the years of Mercury (88 days) and Earth (365 days). It orbits at an average distance of 0.539 AU — comparable to the inner Solar System. Its orbit is mildly elliptical (eccentricity 0.26).

How Was BD+15 2940 b Discovered?

BD+15 2940 b was discovered in 2013 using the radial velocity method, with observations from McDonald Observatory.

The radial velocity method measures the subtle wobble of a star caused by the gravitational pull of an orbiting planet, visible as periodic shifts in the star's light spectrum. The size of the wobble reveals the planet's minimum mass.

How Far Away Is BD+15 2940 b?

BD+15 2940 b is 1,390.8 light-years (426.4 parsecs) from Earth. Light arriving here tonight left the planet about 1,391 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 24,478,080 years to make the journey.

Earth Similarity Index

The Earth Similarity Index (ESI) scores how physically similar a planet is to Earth, from 0 to 1, based on radius, density, escape velocity and surface temperature. BD+15 2940 b scores 0.07, ranking #4,972 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.

The Host Star: BD+15 2940

BD+15 2940

Spectral type
K0
Surface temperature
4,796 K (Sun: 5,772 K)
Mass
1.10 M☉
Radius
14.70 R☉
Luminosity
102.3293 L☉
Age
7.1 billion years (Sun: 4.6)

Planetary System

BD+15 2940 b is the only planet known to orbit BD+15 2940 so far.

BD+15 2940 b — Complete Data

Mass (best estimate)352.78 Earth masses
Orbital period137.48 days
Orbital distance0.539 AU
Eccentricity0.260
Earth Similarity Index0.07
Distance from Earth1,390.8 light-years (426.4 parsecs)
ConstellationSerpens
Discovery methodRadial Velocity
Discovery facilityMcDonald Observatory
Discovery year2013

Data: NASA Exoplanet Archive, last updated 2014-05-14. Earth Similarity Index: PHL @ UPR Arecibo.

Frequently Asked Questions About BD+15 2940 b

Is BD+15 2940 b habitable?

No — BD+15 2940 b orbits too close to its star and is too hot for liquid water to exist on its surface.

How far away is BD+15 2940 b?

BD+15 2940 b is about 1,391 light-years from Earth in the constellation Serpens. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 24,478,080 years to get there.

How long is a year on BD+15 2940 b?

One orbit around BD+15 2940 takes 137.5 Earth days.

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