I would like to know the difference between the stars sirius,alpha centauri & proxima centauri.?

Question

I still dont know which star is closest to the earth!Is it sirius,alpha centauri,xirius or proxima centauri or are all these the names of the same stars?Or is it that alpha centauri and proxima centauri are a binary star system known as sirius?

Answer 1

The Hubblesite has tomes of data and photos on this.

@Quaternios aka AL MOSKOWITZ - lay the **** off or else.  You have no right to post a remark like that.  Everyone here knows you're a demented lunatic with a perverse motive.

Answer 2

Proxima Centauri is the closest star to Earth, it's distance is 4.2 light years away.  

Siriou, Alpha Centauri and Proxima Centauri are three different stars.  

Alpha and Proxima Centauri are both in the constellation

Centaurus.  

Sirius is the brightest star in our night sky, and even though with the naked eye we can only see one star, Sirius is actually a binary star (comprised of Sirius A and Sirius B).  Sirius is also known as the "dog star" and is located in the constellation Canis Major.

Answer 3

"Sirius is the brightest star in the night sky with a visual apparent magnitude of −1.47, almost twice as bright as Canopus, the next brightest star."

"What the naked eye perceives as a single star is actually a binary star system, consisting of a white main sequence star of spectral type A1V, termed Sirius A, and a faint white dwarf companion of spectral type DA2, termed Sirius B."

"Alpha Centauri / α Centauri / α Cen, also known as Rigil Kentaurus, Rigel Kent, or Toliman, is the brightest star in the southern constellation of Centaurus and an established binary star system, Alpha Centauri AB (α Cen AB). It appears to the naked-eye as the third brightest star in the entire night sky, being only outshone by Sirius and Canopus. By total visual magnitude Alpha Centauri AB is −0.27, which is just fractionally brighter than the fourth brightest individual star in the night sky, Arcturus."

"Proxima Centauri (Latin proximus, proxima, proximum: meaning 'next to' or 'nearest to')[7] is a red dwarf star approximately 4.22 light-years away in the constellation of Centaurus. It was discovered in 1915 by Robert Innes, the Director of the Union Observatory in South Africa. The star is thought to be part of the Alpha Centauri system and is the nearest star to the Sun.[4] Because of the star's proximity, Proxima Centauri has been proposed as a destination for interstellar travel.[8]

Proxima Centauri is categorized as a flare star, as it undergoes random increases in luminosity because of magnetic activity.[9] The magnetic field is created by convection of the entire star, and the resulting flare activity produces a total X-ray emission similar to that from the Sun.[10] Proxima Centauri only has about an eighth of the Sun's mass, and consequently it has a very low luminosity. Because of its proximity, the size of this star can be measured directly, giving a diameter only one-seventh the size of the Sun.[4] The relatively low energy production rate and convective stirring of the fuel at the core means that Proxima Centauri will remain on the main sequence—burning hydrogen fuel—for another four trillion years.[11]"

Answer 4

Do not allow this question to go up for voting. Flash Gordon has multiple user names. He is a cheat.

He also goes by Princess Leia and 169 moons.

He always votes on undecided questions 3 times for himself.

Please help me to ban this person from y/a.

Answer 5

Proxima Centauri is the closest star to Earth

Answer 6

First of all, there is no star called Xirius. The other three (Proxima Centauri, Alpha Centauri, and Sirius) are three different stars. Proxima and Alpha Centauri are both part of a single system, actually consisting of three stars, because Alpha Centauri is a double star by itself, with Proxima as a third more distant companion. Sirius is in a totally different direction and is, in fact, a double star in itself. So we have three stars in the Alpha Centauri system (Alpha A, Alpha B, and Proxima) and two in the Sirius system (Sirius A and Sirius B). Alpha A, Alpha B, and Sirius A are all quite bright stars; Proxima and Sirius B much smaller dwarf stars. All of these are quite close to our Sun; some other nearby stars (closer than Sirius) are Barnard's Star, Wolf 359, and BD +36°2147, all quite faint.

Answer 7

Alpha and Proxima Centauri are unrelated to Sirius, but they are the closest stars (other than the sun) to Earth.  Sirius is about twice as far away, but is the brightest star in the sky.  I don't believe there is any star named Xirius.

Sol's three closest stellar neighbors are located in the southeastern corner of Constellation Centaurus, the Centaur. Proxima Centauri (or Alpha Centauri C) is only 4.22 light-years (ly) away (14:29:42.95-62:40:46.14, ICRS 2000.0) but is too dim to be seen with the naked eye. The two bright stars, Alpha Centauri A and B (14:39:36.5-62:50:02.3 and 14:39:35.1-60:50:13.8, ICRS 2000.0), are a little farther away at about 4.36 ly. They form a close binary that is separated "on average" by only about 24 times the Earth-Sun distance -- 23.7 astronomical units (AUs) of an orbital semi-major axis -- which is only slightly greater than the distance between Uranus and the Sun ("Sol").

Intrinsically, Sirius is over 20 times brighter than our Sun and over twice as massive. As Sirius is 8.7 light years distant, it is not the closest star system - the Alpha Centauri system holds this distinction. Sirius is called the Dog Star because of its prominence in the constellation of Canis Majoris (Big Dog). In 1862, Sirius was discovered to be a binary star system with a (twin) companion star, Sirius B, 10,000 times dimmer than the bright primary, Sirius A. Sirius B was the first white dwarf star discovered

Answer 8

Answers above are correct-- just so you understand Alpha Centauri--   a, b, and c,  is a  triple star system about 4.3 light years away-- http://apod.nasa.gov/apod/ap051204.html

Sirius is the brightest star in the Northern sky-- and is not associated with the Alpha Centauri stars

http://www.astro.uiuc.edu/~kaler/sow/sir...

Answer 9

There is no connection between the Alpha Centauri system and the Sirius system, Sirius is about twice as far from earth as Alpha Centauri.

Sirius, also known as the Dog Star, is the furthest of the three stars you listed.  It is approximately 8.5 light years away.  It is a very young binary star system, somewhere between 200 and 300 million years old,  with the brightest star being a main sequence star about twice as massive as our sun,  while the companion is known to be a white dwarf.

Wiki says that both stars were blue stars with Sirius B evolving into a red giant and then  about 125 million years ago leaving the main sequence and becoming a white dwarf.  

I think Wiki might be incorrect on both stars being blue giants.  Astronomy News says that Sirius A is 225 and 250 million years old and that Sirius B went from the Red Giant stage to the White Dwarf stage about 125 million years ago. It could be that when Sirius A was a protostar, Sirius B expanded during its Red Giant stage causing Sirius A to reach the main sequence more quickly and make it a larger star than it would have been absent Sirius B.

Alpha Centauri is depending where you check, either a binary system or a triple star system.  Alpha Centauri the system is the closest star system to us; however Proxima Centauri, a small Red Dwarf, about a fifth of a light year away from the binary star Alpha Centauri AB, is the closest star to us at about 4.2 light years.  There is some dispute as to whether Proxima is a true member of the system or if it was partially captured but will eventually move out of the system.