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Kepler-551 b

Mini Neptune Draco

Kepler-551 b is a mini-Neptune orbiting Kepler-551 in the constellation Draco. It lies about 1,015 light-years from Earth and was discovered in 2016 using the transit method.

2.73×Earth radius
12 dOrbital period
0.30Earth similarity
1,015 lyDistance
2016Discovered

How Big Is Kepler-551 b?

Earth1.00 R⊕Kepler-551 b2.73 R⊕
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Kepler-551 b has a radius of 2.73 times that of Earth.

Is Kepler-551 b in the Habitable Zone?

The position of Kepler-551 b relative to the habitable zone of Kepler-551 cannot be precisely determined from the available orbital data.

Too hot Optimistic habitable zone Conservative habitable zone Too cold

Habitable zone of Kepler-551: 0.279–0.697 AU (conservative: 0.354–0.660 AU), per Kopparapu et al. (2014). Earth orbits the Sun at 1 AU.

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Orbit and Year Length

A year on Kepler-551 b — one full orbit around Kepler-551 — lasts 12.4 Earth days, shorter than Mercury's 88-day year.

How Was Kepler-551 b Discovered?

Kepler-551 b was discovered in 2016 using the transit method, with observations from Kepler.

The transit method watches a star for the tiny, regular dip in brightness that occurs when a planet crosses in front of it. The depth and timing of these dips reveal the planet's size and orbital period.

How Far Away Is Kepler-551 b?

Kepler-551 b is 1,014.9 light-years (311.2 parsecs) from Earth. Light arriving here tonight left the planet around the year 1012. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 17,862,240 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. Kepler-551 b scores 0.30, ranking #1,549 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.

The Host Star: Kepler-551

Kepler-551

Surface temperature
4,286 K (Sun: 5,772 K)
Mass
0.65 M☉
Radius
0.63 R☉
Age
3.8 billion years (Sun: 4.6)

Planetary System

Kepler-551 b is the only planet known to orbit Kepler-551 so far.

Kepler-551 b — Complete Data

Radius2.730 Earth radii (0.244 Jupiter radii)
Orbital period12.38 days
Earth Similarity Index0.30
Distance from Earth1,014.9 light-years (311.2 parsecs)
ConstellationDraco
Discovery methodTransit
Discovery facilityKepler
Discovery year2016

Data: NASA Exoplanet Archive, last updated 2016-05-06. Earth Similarity Index: PHL @ UPR Arecibo.

Frequently Asked Questions About Kepler-551 b

Is Kepler-551 b habitable?

Kepler-551 b is not known to orbit within the habitable zone of Kepler-551, and as a mini-Neptune it is an unlikely candidate for life as we know it.

How far away is Kepler-551 b?

Kepler-551 b is about 1,015 light-years from Earth in the constellation Draco. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 17,862,240 years to get there.

How big is Kepler-551 b compared to Earth?

Kepler-551 b has 2.73 times the radius of Earth.

How long is a year on Kepler-551 b?

One orbit around Kepler-551 takes 12.4 Earth days — short enough that 30 of its years would fit into one Earth year.

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