Proxima Centauri c Facts
Proxima Centauri c is a distant exoplanet candidate orbiting the closest star to the Sun, Proxima Centauri, about 4.24 light years away. It is estimated to be a super-Earth or mini-Neptune with a mass several times that of Earth and an extremely long orbital period of roughly 5.3 years. First proposed through radial velocity data, its existence is still debated, though multiple studies suggest it may be a cold, far out planet well outside the star’s habitable zone. Because of its distance from its star, Proxima Centauri c is expected to be extremely cold and unlikely to support life as we know it, but it remains one of the most intriguing possible planets in our nearest stellar system.
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Proxima Centauri c Location in the Milky Way Galaxy
Local Fluff of Local Bubble
Galactic Orion Arm Spur
26,000 LY from Galactic Center
Proxima Centauri c is 4.2421 Light Years Away from Earth
Unknown Planet Class
Proxima Centauri c
Neptunian Size
12.0 Earth Mass
Moons ?
17,437 Mile Diameter
3.162 Density
1.8885 g
Atmosphere ?
-389 F Average Temp (Frozen)
Proxima Centauri c Tilt Relative to the Plane of Proxima Centauri System
Proxima Centauri c Axial Tilt
Unknown
Unknown Axial Tilt
Proxima Centauri c Seasons
Unknown
Unknown if Seasons Exist
Proxima Centauri c Atmosphere Composition and Pressure
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown Atmospheric Pressure
It is Unknown if Proxima Centauri c has an Atmosphere Due to Extreme Flares from its Star
Proxima Centauri c Weather
Clouds
Unknown
Wind
Unknown
Rain
Unknown
Lightning
Unknown
Proxima Centauri c Surface and Internal Composition
Crust
Silicate Rocks ?
Mantle
Soft Silicates ?
Outer Core
Liquid ?
Inner Core
Solid Iron ?
Solid Nickel ?
Surface Liquid
Unknown
Surface Ice
Unknown
Sub-Surface Liquid
Unknown
Sub-Surface Ice
Unknown
Proxima Centauri c Magnetic Radiation Shield
Unknown Gauss Magnetic Field Strength
It is Unknown if Proxima Centauri c has a Magnetic Field
Proxima Centauri c Similarity to Earth
Unknown
More Data is Needed
Proxima Centauri c Alien Life Chance
Unknown
More Data is Needed
Travel Time to Proxima Centauri c
Chemical Rocket Travel Time
55,046 Earth Years
Fission Rocket Travel Time
85.37 Earth Years
Fusion Rocket Travel Time
42.68 Earth Years
Laser Light Sail Travel Time
21.34 Earth Years
Top 5 Most Asked Questions About Proxima c
(Answered Simply)
How far away is Proxima Centauri c from Earth?
Proxima Centauri c is located in the Proxima Centauri star system, which is the closest known stellar system to Earth. The entire system is about 4.24 light years away, which is roughly 40 trillion kilometers or 25 trillion miles.
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Because Proxima Centauri c orbits a star in that system, it is essentially the same distance from Earth as its host star. Even though it is relatively “close” in cosmic terms, it is still far beyond the reach of current spacecraft, taking thousands of years to travel there with today’s technology.
Is Proxima Centauri c habitable or does it have life?
Proxima Centauri c is not currently considered habitable, and there is no evidence that it hosts life. It orbits far from its star, placing it well outside the traditional “habitable zone” where liquid water could exist on the surface under Earth-like conditions.
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Because of its likely cold temperatures and uncertain atmospheric conditions, scientists think Proxima Centauri c is more likely to be a cold, possibly icy super-Earth or mini-Neptune type world rather than an Earth-like planet. So far, all observations are indirect, and no signs of life or a life supporting atmosphere have been detected.
How big is Proxima Centauri c compared to Earth?
Proxima Centauri c is estimated to be a super-Earth or possibly mini-Neptune, meaning it is significantly larger and more massive than Earth. Based on current measurements, it is thought to have a mass of roughly about 12 times Earth’s mass, though exact values are still uncertain because it hasn’t been directly imaged.
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In terms of size, Proxima Centauri c is believed to be larger in radius than Earth, but scientists don’t yet have a precise measurement of its diameter. Its higher mass suggests stronger gravity than Earth, which would make its surface conditions very different from anything we experience here.
How was Proxima Centauri c discovered?
Proxima Centauri c was discovered indirectly using a method called radial velocity detection, where astronomers look for tiny “wobbles” in a star’s motion caused by the gravitational pull of an orbiting planet. In this case, scientists analyzed long term observations of Proxima Centauri and detected a subtle, repeating signal suggesting a planet with a long orbital period.
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The discovery was first reported in 2020 after researchers combined data from multiple telescopes, including high precision spectrographs. Unlike planets that are directly imaged, Proxima Centauri c has never been seen visually; its existence is inferred entirely from how it affects the motion of its host star.
What is Proxima Centauri c made of and does it have an atmosphere?
Proxima Centauri c has not been directly observed in detail, so its exact composition is still uncertain. Based on its estimated mass, scientists think it is likely a super-Earth or mini-Neptune, meaning it could be made of rock and metal with a thick layer of ice or gas, rather than being a purely Earth-like rocky planet.
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There is currently no confirmed evidence of an atmosphere. If it does have one, it would depend on how it formed and whether it has been able to retain gases over time. Because it is far from its star and difficult to study directly, both its surface conditions and atmospheric properties remain speculative.
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