There is a star near us.
It is very far away. It is small and red. We cannot see it with our eyes. It has planets around it.
Do you like stars?
A tiny red star lives near us.
It is the closest star to our Sun. It is too dim to see with eyes.
This star is much smaller than our Sun. It can flare up and get very bright. This happens because of its magnetic force. The star has planets that move around it. One planet might even have liquid water. This star will shine for a very long time.
It is a very special neighbor in space.
Proxima Centauri is our closest star neighbor.
It is 4.25 light-years away from Earth. You cannot see it with your eyes. It is a red dwarf star. This means it is small and cool. It has only 12.5% of the Sun's mass.
The star is very dense. It is 33 times denser than our Sun.
This star is very active. It is a flare star. It has a magnetic field. This field lets out big bursts of light. We call these stellar flares. These flares can make the star look very bright.
Proxima Centauri has planets. One is named Proxima Centauri b. It is in the habitable zone. This is the area where liquid water might exist. There is also a planet named Proxima Centauri d.
The star will live for a long time. It will shine for four trillion years. It uses its fuel very slowly. This makes it a very long-lasting star.
Proxima Centauri is the closest star to our Sun.
It sits about 4.25 light-years away from Earth. You can find it in the southern constellation of Centaurus. This star is part of the Alpha Centauri star system. It is known as component Alpha Centauri C. It orbits the main pair of stars, Alpha Centauri AB. This orbit takes about 550,000 years to complete.
Because it is so far and small, you cannot see it with your naked eyes.
This star is a red dwarf, which means it is small and cool. It has only 12.5% of the mass of our Sun. However, it is much denser than the Sun. It is about 33 times as dense.
The star is also a flare star. This happens because of magnetic activity inside the star. This activity creates a magnetic field through a process called convection. Convection is when the hot plasma inside the star moves around. This movement causes the star to have sudden, bright bursts of light. These flares can reach temperatures as high as 27 million K.
Robert Innes discovered this star in 1915. Scientists have studied it many times since then. In 2002, researchers used the Very Large Telescope to measure its size. They found its diameter is about one-seventh the size of the Sun. This is about 1.5 times the size of Jupiter.
In 2020, data from the Gaia mission helped find its exact distance. Proxima Centauri has been our closest neighbor for about 32,000 years. It will stay the closest star for another 25,000 years.
Proxima Centauri has its own family of planets.
There is a planet called Proxima Centauri b. It is at least 1.06 times the mass of Earth. This planet orbits in the habitable zone. That is the area where liquid water might exist on a surface. There is also a smaller planet called Proxima Centauri d. It orbits the star every 5.1 days. Scientists also think there might be a third planet called Proxima Centauri c. This one is a candidate, which means they are still checking.
This star will last for a very long time. It will be a main-sequence star for four trillion years. This is because it uses its fuel very slowly. The convection inside the star mixes the fuel well. This helps the star burn almost all of its hydrogen.
Eventually, the star will change into a blue dwarf. Later, it will become a helium white dwarf. Even though it is small, it is a very important part of our cosmic neighborhood.
Proxima Centauri is the closest star to our Sun.
It is located 4.25 light-years away in the southern constellation of Centaurus. This star is a red dwarf, which means it is a small, low-mass star. It belongs to the main sequence on the Hertzsprung-Russell diagram. Specifically, it is classified as an M5.5 spectral type star. This classification means it is at the low-mass end of M-type dwarf stars. Its color is shifted toward red-yellow because of its effective temperature.
The star is part of the larger Alpha Centauri system. It is identified as component Alpha Centauri C. It orbits the Alpha Centauri AB star pair. This orbital period lasts about 550,000 years. Proxima Centauri is about 2.18 degrees southwest of the AB pair. This distance is about four times the angular diameter of the full Moon. Scientists believe Proxima Centauri might have been captured by the binary pair. This could have happened within a star cluster before the cluster dispersed.
The internal structure of Proxima Centauri is very different from our Sun. Because of its low mass, the star is completely convective. Convection is the physical movement of plasma throughout the stellar body. This process transfers energy to the exterior of the star. In the Sun, energy moves through both radiation and convection. In Proxima Centauri, convection circulates the fuel through the core. This means helium ash does not just accumulate in the center. Instead, the helium is mixed throughout the entire star. This efficient mixing allows the star to burn nearly all its hydrogen.
This convection also generates a strong magnetic field. This field causes the star to be a flare star. Magnetic energy is released at the surface as dramatic stellar flares. These flares can increase the star's brightness for a few minutes. Some flares can reach temperatures as high as 27 million K. On May 6, 2019, a massive flare was detected. It reached a far ultraviolet emission of 10^31 erg/s. Even during quiet times, the star's corona is very hot. It stays at 3.5 million K, which is hotter than the Sun's corona.
Proxima Centauri has very different physical measurements than the Sun. Its mass is only about 12.5% of the Sun's mass. This equals approximately 129 Jupiter masses. However, its density is about 33 times higher than the Sun's density. Its actual diameter is about one-seventh the diameter of the Sun. This is roughly 1.5 times the size of Jupiter. The surface gravity is also much higher than Earth's. It is 162 times the surface gravity found on Earth.
Several planets have been found orbiting this nearby star. The first is Proxima Centauri b, which is at least 1.06 times the mass of Earth. It orbits the star every 11.2 Earth days. This planet sits within the habitable zone. This is the region where temperatures allow liquid water to exist. There is also a smaller planet called Proxima Centauri d. It is a sub-Earth that orbits every 5.1 days. Scientists also consider Proxima Centauri c to be a candidate exoplanet. This candidate is described as a sub-Neptune.
The life of Proxima Centauri will be incredibly long. It will remain a main-sequence star for another four trillion years. As it burns hydrogen, it will gradually become a blue dwarf. During this stage, it will become smaller and hotter. It will eventually reach 2.5% of the Sun's luminosity. After the hydrogen is gone, it will become a helium white dwarf. It will not pass through a red giant phase.
Proxima Centauri has a unique place in our local history. It has been the closest star to the Sun for 32,000 years. It will remain the closest star for another 25,000 years. After that, the Alpha Centauri AB pair will take turns being closest. In about 3.5 billion years, Proxima Centauri will leave the system. It will become unbound from the Alpha Centauri pair. It will then move away into space on its own.
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