Kepler-1398 c
Kepler-1398 c is a terrestrial planet orbiting Kepler-1398 in the constellation Cygnus. It lies about 2,780 light-years from Earth and was discovered in 2016 using the transit method.
How Big Is Kepler-1398 c?
Kepler-1398 c has a radius of 1.03 times that of Earth.
Is Kepler-1398 c in the Habitable Zone?
The position of Kepler-1398 c relative to the habitable zone of Kepler-1398 cannot be precisely determined from the available orbital data.
Habitable zone of Kepler-1398: 0.975–2.277 AU (conservative: 1.234–2.159 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-1398 c — one full orbit around Kepler-1398 — lasts 4.14 Earth days, shorter than Mercury's 88-day year.
How Was Kepler-1398 c Discovered?
Kepler-1398 c 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-1398 c?
Kepler-1398 c is 2,779.5 light-years (852.2 parsecs) from Earth. Light arriving here tonight left the planet about 2,780 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 48,919,200 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-1398 c scores 0.29, ranking #1,582 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-1398
Kepler-1398
- Surface temperature
- 6,126 K (Sun: 5,772 K)
- Mass
- 1.13 M☉
- Radius
- 1.18 R☉
- Age
- 3.1 billion years (Sun: 4.6)
The Kepler-1398 Planetary System
Kepler-1398 c is one of 2 known planets in the Kepler-1398 system. Its siblings:
- Kepler-1398 b (Terrestrial)
Kepler-1398 c — Complete Data
| Radius | 1.030 Earth radii (0.092 Jupiter radii) |
|---|---|
| Orbital period | 4.14 days |
| Earth Similarity Index | 0.29 |
| Distance from Earth | 2,779.5 light-years (852.2 parsecs) |
| Constellation | Cygnus |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2016 |
Data: NASA Exoplanet Archive, last updated 2016-05-06. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About Kepler-1398 c
Is Kepler-1398 c habitable?
Kepler-1398 c is not known to orbit within the habitable zone of Kepler-1398, and as a terrestrial planet it is an unlikely candidate for life as we know it.
How far away is Kepler-1398 c?
Kepler-1398 c is about 2,780 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 48,919,200 years to get there.
How big is Kepler-1398 c compared to Earth?
Kepler-1398 c has 1.03 times the radius of Earth.
How long is a year on Kepler-1398 c?
One orbit around Kepler-1398 takes 4.1 Earth days — short enough that 88 of its years would fit into one Earth year.
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