When we were children we would often just gaze at the sky trying to picture what it would be like to see the stars we were only catching a glimpse of from near. Of course as we grew up we understood that as light as all things needs time to reach us, all those stars we wondered about as we were children might not even exist anymore if they were far away enough so that we would see maybe what they looked like 1000 years ago. But even so, we still find exquisite beauty in what our sky offers us and from Earth we are able to see some of the biggest and brightest stars astronomers have discovered thus far. But which ones are closest to our home planet?
Well apart from our Sun which, of course, is the nearest star to Earth, Proxima Centauri is located at a mere 4.24 LY(Light Years) away. It is described as a red dwarf (a star that is relatively cool and small, of orange color, belonging to the M spectral type, having low luminosity) and it is approximately an eighth of the Sun’s mass but 40 times denser than it.
Or Rigel Kent belongs to the Centaurus constellation and appears as a single object to the unaided eye. It is however a star system that is formed of two stars that orbit around a common center of mass and their combined visual magnitude have earned Rigel Kent the third place among the brightest stars seen from Earth, after Sirius B and Canopus. It is located 4.3 LY from Earth.
This red dwarf is located about 6LY away from Earth and belongs to the Ophiuchus constellation. But in spite of its proximity, it is not visible to the naked eye (it is bright in infrared light). Aged at about 7-12 billion years, Barnard’s Star is older than the Sun and astronomers believe that it may belong to the oldest stars in our galaxy.
Situated in the Leo constellation, 7.8 LY from the Earth, this red dwarf is also not visible without a telescope as it is one of the lowest-mass stars known. It is also described as a flare star (such stars undergo sudden increases in brightness that happen every few days) and is considered by astronomers as being just above the minimum limit at which hydrogen fusion is possible through proton-proton reactions.
This binary star system, also named Gliese 65 or UV Ceti is located at approximately 8.4 LY from Earth and belongs to the Cetus Constellation. It was discovered in 1948 by Jacob Luyten and astronomers have described it as the archetype for flare stars even though it was not the first such star to be discovered.
This is the brightest star on the sky, both because of proximity and intrinsic luminosity is located at approximately 8.6 LY from Earth. Also a binary star system, it is formed by Sirius A, a white main-sequence star, and Sirius B, a white dwarf and is the brightest star on our sky, after our Sun of course. The interesting thing is that over the next 60000 years or so, it will be moving closer to our solar system and will therefore increase its luminosity.
Ross 154, Ross 248 and Ross 128
These 3 stars are situated 9.4, 10.4 respectively 10.9 LY from the Earth and are the next three stars after Sirius closest to the Earth. Ross 154 belongs to the Sagittarius constellation and is too faint to be seen without a telescope, Ross 248 is situated in the constellation of Andromeda and is also invisible to the naked eye, and Ross 128 belongs to the constellation of Virgo, also much to faint to be seen without a telescope. They are all red dwarfs.
Also known as Luyten 789-6 or Gliese 866, Ez Aquarii is a triple star system whose components are all red dwarfs belonging to the M spectral type. As Sirius, this star system is also approaching our Solar System and in about 32000 years it will be at its closest to us.
Procyon A is a white main sequence star belonging to the Procyon star system, located approximately 11.4 light years from the Earth. This star, the brightest in the Canis Minor constellation, appears so bright to us not because of its intrinsic luminosity but because of the proximity to Earth. Together with Sirius and Betelegeuse it forms the Winter Triangle.
This faint white dwarf is the second star in the Procyon binary system was visually confirmed in 1896. Procyon emits most of its light in UV spectrum and therefore the possibility that life may be possible around this star is considered unlikely.
And even if you are interested in the scientific aspects or not, there is no denying the beauty and serenity that watching the stars gives us. But the next time you watch the night’s sky consider that even if these stars seem bright on our sky, the truly luminous, large stars like Betelegeuse, RW Cephei, Mu Cephei, Anatares who range from 800 to 1600 times the Suns radius are not as luminous as other stars just because of their distance from the Earth.