Cosmos Redshift 7
Cosmos Redshift 7 (also known as COSMOS Redshift 7, Galaxy Cosmos Redshift 7, Galaxy CR7 or CR7) is a high-redshift Lyman-alpha emitter galaxy. At a redshift z = 6.6, the galaxy is observed as it was about 800 million years after the Big Bang, during the epoch of reionisation. With a light travel time of 12.9 billion years, it is one of the oldest, most distant galaxies known.
|Cosmos Redshift 7|
Artist’s impression of CR7.
|Observation data (Reionization epoch)|
|Right ascension||10h 00m 58.005s|
|Declination||+01° 48′ 15.251″|
|Distance||12.9 billion light-years|
|Notable features||123 Galaxy Cosmos Redshift 7 is reported to be three times brighter than the brightest distant galaxy known up to the time of its discovery and to contain some of the earliest first stars that produced the chemical elements needed for the later formation of planets and life as it is known.|
|COSMOS Redshift 7; Galaxy Cosmos Redshift 7; Galaxy CR7; CR7|
CR7 shows some of the expected signatures of Population III stars i.e. the first generation of stars produced during early galaxy formation. These signatures were detected in a bright pocket of blue stars; the rest of the galaxy contains redder Population II stars.
Galaxy Cosmos Redshift 7 contains old Population II (metal-poor) and Population III (extremely metal-poor) stars, according to astronomers, and is three times brighter than the brightest distant galaxies (redshift, z > 6) detected up to the time of its discovery.
Astronomers led by David Sobral, a Reader in Astrophysics at the University of Lancaster, used the Very Large Telescope (VLT) at the European Southern Observatory—with help from the W. M. Keck Observatory, Subaru Telescope and the NASA/ESA Hubble Space Telescope—made the discovery. The research team included members of the University of California, Riverside, University of Geneva, University of Leiden and University of Lisbon. The name of the galaxy (Cosmos Redshift 7 Galaxy) was inspired by football player Cristiano Ronaldo, who is also popularly known as CR7.
- Sobral, David; Matthee, Jorryt; Darvish, Behnam; Schaerer, Daniel; Mobasher, Bahram; Röttgering, Huub J. A.; Santos, Sérgio; Hemmati, Shoubaneh (4 June 2015). "Evidence For POPIII-Like Stellar Populations In The Most Luminous LYMAN-α Emitters At The Epoch Of Re-Ionisation: Spectroscopic Confirmation". The Astrophysical Journal. 808 (2): 139. arXiv:1504.01734. Bibcode:2015ApJ...808..139S. doi:10.1088/0004-637x/808/2/139.
- Overbye, Dennis (17 June 2015). "Astronomers Report Finding Earliest Stars That Enriched Cosmos". New York Times. Retrieved 17 June 2015.
- "Best Observational Evidence of First Generation Stars in the Universe" (Press release). European Southern Observatory. 17 June 2015.
- Staff (17 June 2015). "Brightest galaxy and first-generation stars". Earth & Sky. Retrieved 17 June 2015.
- Pittalwala, Iqbal (17 June 2015). "Astronomers Find Best Observational Evidence of First Generation Stars in the Universe". University of California, Riverside. Retrieved 17 June 2015.
- Matthee, Jorryt; Sobral, David; et al. (21 July 2015). "Identification of the brightest Lyalpha emitters at z=6.6: implications for the evolution of the luminosity function in the re-ionisation era". MNRAS. 451 (1): 4919–4936. arXiv:1502.07355. Bibcode:2015MNRAS.451..400M. doi:10.1093/mnras/stv947.
- Staff (17 June 2015). "Traces of Earliest Stars That Enriched Cosmos Are Spied". New York Times. Retrieved 17 June 2015.
- Staff (18 June 2015). "Cristiano Ronaldo: CR7 name given to discovered galaxy". BBC. Retrieved 18 June 2015.
- Staff (18 June 2015). "Cristiano Ronaldo: CR7 gets his own galaxy". CNN. Retrieved 18 June 2015.