Kepler-411 d
Kepler-411 d is a sub-Neptune orbiting the K2 V star Kepler-411 in the constellation Cygnus. It lies about 501 light-years from Earth and was discovered in 2018 using the transit method.
How Big Is Kepler-411 d?
Kepler-411 d has a radius of 3.32 times that of Earth. Its mass is 15.2 times that of Earth, giving it a density of 2.30 g/cm³ — between that of rocky and gaseous planets.
Is Kepler-411 d in the Habitable Zone?
The position of Kepler-411 d relative to the habitable zone of Kepler-411 cannot be precisely determined from the available orbital data.
Temperature on Kepler-411 d
The equilibrium temperature of Kepler-411 d is about 410 K (137 °C) — hotter than anywhere on Earth. This estimate ignores any atmosphere, which could change surface temperatures dramatically — Earth's greenhouse effect adds about 33 °C.
Orbit and Year Length
A year on Kepler-411 d — one full orbit around Kepler-411 — lasts 58.0 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.279 AU — closer to its star than Mercury is to the Sun. Its orbit is mildly elliptical (eccentricity 0.13).
How Was Kepler-411 d Discovered?
Kepler-411 d was discovered in 2018 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-411 d?
Kepler-411 d is 501.2 light-years (153.7 parsecs) from Earth. Light arriving here tonight left the planet around the year 1525. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 8,821,120 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-411 d scores 0.46, ranking #318 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-411
Kepler-411 d belongs to a system of 2 stars; it orbits Kepler-411.
Kepler-411
- Spectral type
- K2 V
- Mass
- 0.87 M☉
- Radius
- 0.82 R☉
- Age
- 0.2 billion years (Sun: 4.6)
The Kepler-411 Planetary System
Kepler-411 d is one of 4 known planets in the Kepler-411 system. Its siblings:
- Kepler-411 b (Super Earth)
- Kepler-411 c (Neptune-like)
- Kepler-411 e (Neptune-like)
Kepler-411 d — Complete Data
| Radius | 3.319 Earth radii (0.296 Jupiter radii) |
|---|---|
| Mass | 15.20 Earth masses (0.048 Jupiter masses) |
| Density | 2.30 g/cm³ (Earth: 5.51) |
| Orbital period | 58.02 days |
| Orbital distance | 0.279 AU |
| Eccentricity | 0.128 |
| Equilibrium temperature | 410 K (137 °C) |
| Earth Similarity Index | 0.46 |
| Distance from Earth | 501.2 light-years (153.7 parsecs) |
| Constellation | Cygnus |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2018 |
Data: NASA Exoplanet Archive, last updated 2019-07-19. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About Kepler-411 d
Is Kepler-411 d habitable?
Kepler-411 d is not known to orbit within the habitable zone of Kepler-411, and as a sub-Neptune it is an unlikely candidate for life as we know it.
How far away is Kepler-411 d?
Kepler-411 d is about 501 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 8,821,120 years to get there.
How big is Kepler-411 d compared to Earth?
Kepler-411 d has 3.32 times the radius of Earth and about 15.2 times its mass.
How long is a year on Kepler-411 d?
One orbit around Kepler-411 takes 58.0 Earth days.