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Kepler-603 b

Mini Neptune Cygnus

Kepler-603 b is a mini-Neptune orbiting Kepler-603 in the constellation Cygnus. It lies about 5,022 light-years from Earth and was discovered in 2016 using the transit method.

2.65×Earth radius
21 dOrbital period
0.24Earth similarity
5,022 lyDistance
2016Discovered

How Big Is Kepler-603 b?

Earth1.00 R⊕Kepler-603 b2.65 R⊕
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Kepler-603 b has a radius of 2.65 times that of Earth.

Is Kepler-603 b in the Habitable Zone?

The position of Kepler-603 b relative to the habitable zone of Kepler-603 cannot be precisely determined from the available orbital data.

Too hot Optimistic habitable zone Conservative habitable zone Too cold

Habitable zone of Kepler-603: 0.764–1.800 AU (conservative: 0.968–1.706 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 Kepler-603 b — one full orbit around Kepler-603 — lasts 21.1 Earth days, shorter than Mercury's 88-day year.

How Was Kepler-603 b Discovered?

Kepler-603 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-603 b?

Kepler-603 b is 5,021.6 light-years (1,539.6 parsecs) from Earth. Light arriving here tonight left the planet about 5,022 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 88,380,160 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-603 b scores 0.24, ranking #3,408 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.

The Host Star: Kepler-603

Kepler-603

Surface temperature
5,808 K (Sun: 5,772 K)
Mass
1.01 M☉
Radius
1.01 R☉
Age
4.4 billion years (Sun: 4.6)

The Kepler-603 Planetary System

Kepler-603 b is one of 3 known planets in the Kepler-603 system. Its siblings:

Kepler-603 b — Complete Data

Radius2.650 Earth radii (0.236 Jupiter radii)
Orbital period21.05 days
Earth Similarity Index0.24
Distance from Earth5,021.6 light-years (1,539.6 parsecs)
ConstellationCygnus
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-603 b

Is Kepler-603 b habitable?

Kepler-603 b is not known to orbit within the habitable zone of Kepler-603, and as a mini-Neptune it is an unlikely candidate for life as we know it.

How far away is Kepler-603 b?

Kepler-603 b is about 5,022 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 88,380,160 years to get there.

How big is Kepler-603 b compared to Earth?

Kepler-603 b has 2.65 times the radius of Earth.

How long is a year on Kepler-603 b?

One orbit around Kepler-603 takes 21.1 Earth days — short enough that 17 of its years would fit into one Earth year.

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