The South African astronomy community will celebrate the centenary of the discovery of the Sun's nearest known stellar neighbour, red dwarf Proxima Centauri, tomorrow at the Johannesburg Observatory.
The South African astronomy community will celebrate the centenary of the discovery of the Sun's nearest known stellar neighbour, red dwarf Proxima Centauri, tomorrow at the Johannesburg Observatory.
2015 marks the 100th year since the major astronomy discovery in South Africa in October 1915 by the former director of the Union Observatory in Johannesburg, Dr Robert Innes.
The exact date of the discovery is not known, but evidence suggests that it was just before 5 October 1915. It has been established that the late Innes wrote a paper to announce his discovery and sent it to the printers on 5 October 1915. The paper is entitled 'A faint star of large proper motion' and is dated 12 October 1915.
Innes made this important discovery using the Franklin-Adams telescope. The Franklin-Adams telescope was built in England in 1902 and brought to South Africa to photograph the southern sky. The discovery of Proxima Centauri was a major development in astronomy because for many years it was believed that Alpha was the closest star to the Sun.
Innes’s crucial discovery disproved this long-held belief. Innes suggested that the newly-discovered star is part of the three-star Alpha Centauri System, with the other two stars being Alpha Centauri and Beta Centauri – the pointer stars of the Southern Cross. For many years astronomers believed that Alpha Centauri was the closest star to our solar system.
In 1917 Innes proposed that the new star be called Proxima Centauri. Proxima is the Latin word for “nearest”. It has the description 'red dwarf' according to a system that plots the temperature of stars against their luminosity, or their colour against their absolute magnitude.
The Union Observatory started as the Transvaal Meteorological Observatory in 1903. In 1912 it was renamed the Union Observatory and is now known as the South African Agency for Science and Technology Advancement (SAASTA) Johannesburg Observatory.
SAASTA and the National Research Foundation (NRF) are co-ordinating the 100-year celebrations. As part of the build-up to the main event on 8 October 2015, a number of events took place aimed to inform the general public about the discovery. SAASTA Manager of Science Awareness Platform Shadrack Mkansi said these included the National Research Foundation public lectures.
He said teaching materials were also distributed to science teachers. Additional source: http://astronomy.swin.edu.au/ NOW WATCH THE VIDEO:
Hubble's shot of Proxima Centauri, our nearest neighbour Shining brightly in this Hubble image is our closest stellar neighbour: Proxima Centauri. Proxima Centauri lies in the constellation of Centaurus (The Centaur), just over four light-years from Earth. Although it looks bright through the eye of Hubble, as you might expect from the nearest star to the Solar System, Proxima Centauri is not visible to the naked eye.
Its average luminosity is very low, and it is quite small compared to other stars, at only about an eighth of the mass of the sun. However, on occasion, its brightness increases.
Proxima is what is known as a flare star, meaning that convection processes within the star’s body make it prone to random and dramatic changes in brightness. The convection processes not only trigger brilliant bursts of starlight but, combined with other factors, mean that Proxima Centauri is in for a very long life.
Astronomers predict that this star will remain middle-aged — or a "main sequence" star in astronomical terms — for another four trillion years, some 300 times the age of the current Universe. These observations were taken using Hubble’s Wide Field and Planetary Camera 2 (WFPC2).
Proxima Centauri is actually part of a triple star system — its two companions, Alpha Centauri A and B, lie out of frame. Although by cosmic standards it is a close neighbour, Proxima Centauri remains a point-like object even using Hubble’s eagle-eyed vision, hinting at the vast scale of the Universe around us.
– ESA/Hubble & NASA
