Loading AI tools
Extremely metal poor star in the constellation Phoenix From Wikipedia, the free encyclopedia
HE0107-5240 is an extremely metal-poor Population II star, located roughly 36000 light-years away from Earth. It is one of the most metal-poor stars known in our Galaxy, with a metallicity [Fe/H] = −5.2±0.2;[3] i.e. it has just 1/160000 of the metal that the Sun has. Because of its very low metallicity, it is believed to be one of the earliest Population II stars to have formed. If so, then it is also very old, with an age of roughly 13 billion years. Because the star is not completely metal-free, it does not belong to the first generation of stars (the hypothetical Population III). These stars converted the pristine hydrogen, helium, and lithium formed by the Big Bang into heavier elements, such as carbon, oxygen, and metals.
The ultra-metal-poor star HE0107-5240 | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Phoenix |
| Right ascension | 01h 09m 29.1s[1] |
| Declination | −52° 24′ 20″ |
| Apparent magnitude (V) | 15.86 |
| Astrometry | |
| Proper motion (μ) | RA: +2.357[2] mas/yr Dec.: −3.826[2] mas/yr |
| Parallax (π) | 0.1064 ± 0.0195 mas[2] |
| Distance | 36000 ly |
| Details | |
| Mass | 1.789[2] M☉ |
| Radius | 3.7[2] R☉ |
| Luminosity | 14[2] L☉ |
| Temperature | 5,765[2] K |
| Metallicity [Fe/H] | −5.3 [3] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
The star is relatively small for a star of the early universe, which accounts for its old age: massive stars die quickly. To help explain why this star is so small, it is hypothesized it was once part of a binary star system.[4] [5]
HE0107-5240 was found by Norbert Christlieb and colleagues at the University of Hamburg in Germany as a byproduct of the Hamburg/ESO Survey for faint quasars with the 1m ESO Schmidt telescope. Follow-up observations were made at the Siding Spring 2.3 m Telescope and high-resolution spectra were taken at the European Southern Observatory in Chile, using one of the units of the Very Large Telescope. In 2005, a second star with an even smaller iron abundance, HE 1327-2326 ([Fe/H]=-5.4), was found, also in the Hamburg/ESO survey. In 2014 an even more metal poor star was announced: SMSS J031300.36−670839.3.[6]
Other ultra low metallicity / ultra metal poor stars
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.
