MASCARA-1 b
MASCARA-1 b is a hot Jupiter orbiting MASCARA-1 in the constellation Equuleus. It lies about 595 light-years from Earth and was discovered in 2017 using the transit method.
How Big Is MASCARA-1 b?
MASCARA-1 b has a radius of 17.90 times that of Earth, or 1.60 times the radius of Jupiter.
Is MASCARA-1 b in the Habitable Zone?
The position of MASCARA-1 b relative to the habitable zone of MASCARA-1 cannot be precisely determined from the available orbital data.
Temperature on MASCARA-1 b
The equilibrium temperature of MASCARA-1 b is about 2,594 K (2,321 °C) — hot enough to melt many metals. 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 MASCARA-1 b — one full orbit around MASCARA-1 — lasts 2.15 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.040 AU — closer to its star than Mercury is to the Sun. Its orbit is nearly circular (eccentricity 0.000).
How Was MASCARA-1 b Discovered?
MASCARA-1 b was discovered in 2017 using the transit method, with observations from Multiple Observatories.
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 MASCARA-1 b?
MASCARA-1 b is 594.5 light-years (182.3 parsecs) from Earth. Light arriving here tonight left the planet around the year 1432. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 10,463,200 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. MASCARA-1 b scores 0.05, ranking #5,269 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: MASCARA-1
MASCARA-1
- Surface temperature
- 7,490 K (Sun: 5,772 K)
- Mass
- 1.90 M☉
- Radius
- 2.08 R☉
- Luminosity
- 12.1001 L☉
- Age
- 0.8 billion years (Sun: 4.6)
Planetary System
MASCARA-1 b is the only planet known to orbit MASCARA-1 so far.
MASCARA-1 b — Complete Data
| Radius | 17.901 Earth radii (1.597 Jupiter radii) |
|---|---|
| Orbital period | 2.15 days |
| Orbital distance | 0.040 AU |
| Eccentricity | 0.000 |
| Equilibrium temperature | 2,594 K (2,321 °C) |
| Earth Similarity Index | 0.05 |
| Distance from Earth | 594.5 light-years (182.3 parsecs) |
| Constellation | Equuleus |
| Discovery method | Transit |
| Discovery facility | Multiple Observatories |
| Discovery year | 2017 |
Data: NASA Exoplanet Archive, last updated 2023-01-18. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About MASCARA-1 b
Is MASCARA-1 b habitable?
MASCARA-1 b is not known to orbit within the habitable zone of MASCARA-1, and as a hot Jupiter it is an unlikely candidate for life as we know it.
How far away is MASCARA-1 b?
MASCARA-1 b is about 595 light-years from Earth in the constellation Equuleus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 10,463,200 years to get there.
How big is MASCARA-1 b compared to Earth?
MASCARA-1 b has 17.90 times the radius of Earth.
How long is a year on MASCARA-1 b?
One orbit around MASCARA-1 takes 2.1 Earth days — short enough that 170 of its years would fit into one Earth year.
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