Kepler-441 b
Kepler-441 b is a super-Earth orbiting Kepler-441 in the constellation Draco. It lies about 874 light-years from Earth and was discovered in 2015 using the transit method.
How Big Is Kepler-441 b?
Kepler-441 b has a radius of 1.64 times that of Earth.
Is Kepler-441 b in the Habitable Zone?
Kepler-441 b orbits beyond the outer edge of the habitable zone of Kepler-441. At that distance, any surface water would almost certainly be frozen.
Habitable zone of Kepler-441: 0.240–0.597 AU (conservative: 0.304–0.566 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 ›
Temperature on Kepler-441 b
Kepler-441 b receives 0.21 times the stellar energy that Earth gets from the Sun.
Orbit and Year Length
A year on Kepler-441 b — one full orbit around Kepler-441 — lasts 207.2 Earth days, between the years of Mercury (88 days) and Earth (365 days). It orbits at an average distance of 0.640 AU — comparable to the inner Solar System. Its orbit is mildly elliptical (eccentricity 0.10).
How Was Kepler-441 b Discovered?
Kepler-441 b was discovered in 2015 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-441 b?
Kepler-441 b is 874.1 light-years (268.0 parsecs) from Earth. Light arriving here tonight left the planet around the year 1152. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 15,384,160 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-441 b scores 0.51, ranking #239 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-441
Kepler-441
- Surface temperature
- 4,340 K (Sun: 5,772 K)
- Mass
- 0.57 M☉
- Radius
- 0.55 R☉
- Luminosity
- 0.0889 L☉
- Age
- 1.9 billion years (Sun: 4.6)
Planetary System
Kepler-441 b is the only planet known to orbit Kepler-441 so far.
Kepler-441 b — Complete Data
| Radius | 1.640 Earth radii (0.150 Jupiter radii) |
|---|---|
| Orbital period | 207.25 days |
| Orbital distance | 0.640 AU |
| Eccentricity | 0.100 |
| Stellar irradiation | 0.21× Earth |
| Earth Similarity Index | 0.51 |
| Distance from Earth | 874.1 light-years (268.0 parsecs) |
| Constellation | Draco |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2015 |
Data: NASA Exoplanet Archive, last updated 2015-01-06. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About Kepler-441 b
Is Kepler-441 b habitable?
No — Kepler-441 b orbits outside the habitable zone of Kepler-441 and is likely too cold for liquid water on its surface.
How far away is Kepler-441 b?
Kepler-441 b is about 874 light-years from Earth in the constellation Draco. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 15,384,160 years to get there.
How big is Kepler-441 b compared to Earth?
Kepler-441 b has 1.64 times the radius of Earth.
How long is a year on Kepler-441 b?
One orbit around Kepler-441 takes 207.2 Earth days.
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