VVV CL001

VVVCL001
VVVCL001
	A image from the Vista Variables in the Via Lactea (VVV) survey showing VVV CL001 located inconspicuously to the left while UKS 1 is on the right
Observation data
Constellation	Sagittarius
Right ascension	17h 54m 37.17s
Declination	-24° 4' 51.34"
Distance	26,800 ly (8.22 kpc)
Physical characteristics
Estimated age	11.9 gya
Notable features	One of the most metal poor globular clusters
	See also: Globular cluster, List of globular clusters

VVV CL001 is a globular cluster located around 8.22 kiloparsecs from Earth in the constellation of Sagittarius.^[1] It is the most metal poor globular cluster discovered around the Milky Way. ^[2] It is an old globular cluster with an age of 11.9 billion years. VVV CL001 is likely an ancient relic that was left behind by a past galactic merger by a massive galaxy early in the evolution of the Milky Way galaxy.^[2] It has a mass of 1.5x10^5 solar masses.^[3]

It may be in a physical binary with another globular cluster known as UKS 1 however it is still being decided if they are an actual binary or have similar radial velocity.^[4]

Discovery

Area of the Milky Way mapped by the VVV and VVVX surveys

VVV CL001 was discovered by using the VISTA Variables in the Via Lactea (VVV) survey. It has several aims such as resolving the three-dimensional structure of the Milky Way galaxy by precisely measuring the distribution of RR Lyrae, Cepheids, and red clump stars.^[5] Another aim of the VVV survey is to accurately measure the physical parameters of known globular clusters and search for new ones. It was this which discovered VVV CL001.^[4]

References

^ [email protected]. "VISTA view of the newly discovered globular cluster VVV CL001 and its brighter companion". www.eso.org (in French). Retrieved 2025-06-12.
^ ^a ^b Fernández-Trincado, José G.; Minniti, Dante; Souza, Stefano O.; Beers, Timothy C.; Geisler, Doug; Bidin, Christian Moni; Villanova, Sandro; Majewski, Steven R.; Barbuy, Beatriz; Pérez-Villegas, Angeles; Henao, Lady; Romero-Colmenares, María; Roman-Lopes, Alexandre; Lane, Richard R. (2021). "VVV CL001: Likely the Most Metal-poor Surviving Globular Cluster in the Inner Galaxy". The Astrophysical Journal Letters. 908 (2): L42. arXiv:2102.01088. Bibcode:2021ApJ...908L..42F. doi:10.3847/2041-8213/abdf47.
^ "VVV-CL001". people.smp.uq.edu.au. Retrieved 2025-06-12.
^ ^a ^b Minniti, D.; Hempel, M.; Toledo, I.; Ivanov, V. D.; Alonso-García, J.; Saito, R. K.; Catelan, M.; Geisler, D.; Jordán, A.; Borissova, J.; Zoccali, M.; Kurtev, R.; Carraro, G.; Barbuy, B.; Clariá, J. (2011-03-01). "Discovery of VVV CL001 - A low-mass globular cluster next to UKS 1 in the direction of the Galactic bulge". Astronomy & Astrophysics. 527: A81. arXiv:1012.2450. Bibcode:2011A&A...527A..81M. doi:10.1051/0004-6361/201015795. ISSN 0004-6361.
^ Saito, R. K.; Hempel, M.; Alonso-García, J.; Lucas, P. W.; Minniti, D.; Alonso, S.; Baravalle, L.; Borissova, J.; Caceres, C.; Chené, A. N.; Cross, N. J. G.; Duplancic, F.; Garro, E. R.; Gómez, M.; Ivanov, V. D. (2024-09-01). "The VISTA Variables in the Vía Láctea extended (VVVX) ESO public survey: Completion of the observations and legacy". Astronomy & Astrophysics. 689: A148. arXiv:2406.16646. Bibcode:2024A&A...689A.148S. doi:10.1051/0004-6361/202450584. ISSN 0004-6361.