Bedin I Explained

Bedin I
Epoch:J2000
Constellation Name:Pavo
Dist Ly: Mpc
Appmag V:19.94
Absmag V:−9.76
Size:840 × 340 pc
Size V:20" × 8"

Bedin I is a dwarf spheroidal galaxy located in the constellation Pavo. It is situated around 28.38 million light-years from Earth, behind the globular cluster NGC 6752. Bedin I is possibly one of the oldest galaxies known, having formed around 10–13 billion years ago, and is one of the most isolated dwarf galaxies known, situated around 2.12 million light-years away from NGC 6744, its nearest neighbor with which it may be physically associated. As such, it has been deemed by astronomers as a "fossil" from the early universe. It was accidentally discovered by Italian astronomer Luigi Bedin, whose team was studying white dwarfs in NGC 6752 using the Hubble Space Telescope in September 2018; the discovery was announced in a paper published in January 2019.

Nomenclature

Bedin I, pronounced,[1] was named by its discovery team after their leader, Luigi Bedin,[2] who is a researcher at the National Institute for Astrophysics's observatory in Padua, Italy.[2] [3] He was credited as the galaxy's sole discoverer.[4] Bedin and the team opted to avoid the galaxy being given "an anonymous identification based on its coordinates."[5]

Characteristics

Bedin I is an isolated dwarf spheroidal galaxy located around 8.7 megaparsecs, or around 28.38 million light-years, from Earth,[6] with similar characteristics to KKR 25 and the Tucana Dwarf Galaxy. It is estimated to be around 840 by 340 parsecs, or 2,700 by 1,100 light-years, in size, which is a fifth the size of the Large Magellanic Cloud. At a metallicity of −1.3, the galaxy's population is made up of metal-poor red giant stars, and its luminosity is roughly a thousand times dimmer than the Milky Way Galaxy,[4] [7] at an absolute magnitude of −9.76. Bedin I is believed to have formed around 10–13 billion years ago with no star formation having occurred since then,[8] making it one of the oldest galaxies known.[8] [9] Bedin I is also possibly the most isolated dwarf galaxy known,[8] located at least 650 kiloparsecs, or 2.12 million light-years, from its nearest neighbor, the intermediate spiral galaxy NGC 6744; the Milky Way and Andromeda galaxies are separated by a similar distance. A physical association with NGC 6744 has been speculated however, due to the close angular distance between the galaxies, and their similar physical distances from Earth. Its age, isolation, and lack of interaction with other galaxies has led to the galaxy being deemed a "fossil" from the early universe.[9] [6]

Observation

Bedin I is located in the constellation Pavo,[5] at a right ascension of and declination of . The galaxy is situated behind a group of unnamed foreground stars within the globular cluster NGC 6752.[10] Bedin I measures around 20 by 8 arcseconds across and has an apparent magnitude of 19.94, although its visibility is significantly decreased by NGC 6752, one of the brightest globular clusters in the sky with an apparent magnitude of 5.4.[11] [12] Bedin I was accidentally discovered by Luigi Bedin's team researching white dwarfs in the cluster in an effort to better determine the cluster's age.[2] [7] [10] The galaxy partially appeared in the field of view during program GO-15096 of the Hubble Space Telescope, led by principal investigator Luigi R. Bedin, which occurred between 7 and 18 September 2018. The program, which saw the Wide Field Channel (WFC) of the Advanced Camera for Surveys (ACS) pointed at NGC 6752 for 75 exposures lasting 1,270 seconds each, was conducted over 40 orbits; these exposures were able to capture objects with an apparent magnitude above 30. Five of the orbits failed however, due to poor guide star acquisition. The journal Monthly Notices of the Royal Astronomical Society: Letters published the team's three-part scientific paper on findings from the program on 31 January 2019, with the first part dedicated to the discovery of Bedin I.[9] A second program of 40 orbits, GO-15491, is currently scheduled for late 2019.

See also

References

NotesSources

  1. Bedin. Luigi. Salaris. Maurizio. Rich. R. Michael. Richer. Harvey. Anderson. Jay. Bettoni. Daniela. Nardiello. Domenico. Milone. Antonio P.. Marino. A. F.. Libralato. Mattia. Bellini. Andrea. Dieball. Andrea. Bergeron. Pierre. Burgasser. Adam J.. Apai. Daniel. The HST Large Programme on NGC 6752. I. Serendipitous discovery of a dwarf Galaxy in background. Monthly Notices of the Royal Astronomical Society: Letters. 10 January 2019. 484. 1. L54–L58. 10.1093/mnrasl/slz004. 31 January 2019. Oxford University Press. https://web.archive.org/web/20190131222539/https://academic.oup.com/mnrasl/article/484/1/L54/5288002. 31 January 2019. live. . free. 10150/634469. free.
  2. Web site: Plait. Phil. Phil Plait. Astronomers accidentally discover a nearby galaxy in a Hubble image!. Syfy Wire. 2 February 2019. https://web.archive.org/web/20190202000138/https://www.syfy.com/syfywire/astronomers-accidentally-discover-a-nearby-galaxy-in-a-hubble-image. 2 February 2019. 1 February 2019. live.

Citations

External links

Notes and References

  1. 6 February 2019. Hubble discovers nearby galaxy - Bedin 1. English. https://ghostarchive.org/varchive/youtube/20211116/yn3WWVzpT_E. 2021-11-16 . live. 21 February 2019. 3:41. Launch Pad Astronomy, YouTube. ...designated Bedin I.
  2. Web site: Wall. Mike. Hubble Telescope Discovers 'Living Fossil' Galaxy in Our Milky Way's Backyard. Space.com. 1 February 2019. https://web.archive.org/web/20190201022347/https://www.space.com/43191-hubble-telescope-living-fossil-galaxy-discovery.html. 1 February 2019. 31 January 2019. The find was fortuitous. An international team of astronomers was using Hubble's Advanced Camera for Surveys instrument to study white dwarfs [...] nicknamed Bedin 1, after discovery team leader L. R. Bedin of the INAF-Osservatorio Astronomico di Padova in Italy.... live.
  3. Web site: Instituto de Astrofísica de Canarias. After the Kepler supernova explosion, no survivors were left behind . Phys.org. 1 February 2019. https://web.archive.org/web/20190201021826/https://phys.org/news/2018-08-kepler-supernova-explosion-survivors-left.html. 1 February 2019. 1 August 2018. ...says Luigi Bedin, researcher at Osservatorio Astronomico di Padova (INAF). live. Instituto de Astrofísica de Canarias .
  4. Web site: Freeman. David. David Freeman (journalist). Tiny 'oddball' galaxy discovered lurking in our cosmic backyard. NBC News MACH. 1 February 2019. https://web.archive.org/web/20190201053923/https://www.nbcnews.com/mach/science/tiny-oddball-galaxy-discovered-lurking-our-cosmic-backyard-ncna965546. 1 February 2019. 31 January 2019. The newfound galaxy, dubbed Bedin 1 in an acknowledgment of the scientist's singular role in its discovery [...] It's about 30 times smaller than the Milky Way and a thousand times dimmer.. live.
  5. Web site: Dvorsky. George. Astronomers Accidentally Discover a Hidden Galaxy Right Next Door. Gizmodo. 2 February 2019. https://web.archive.org/web/20190202010910/https://gizmodo.com/astronomers-accidentally-discover-a-hidden-galaxy-right-1832262574?IR=T. 2 February 2019. 1 February 2019. Bedin 1 is located in the Pavo constellation [...] Bedin said he pleased with the galaxy's new name, saying it was "nice to adopt a nickname from one of its discoverers instead of an anonymous identification based on its coordinates.". live.
  6. Web site: Griffin. Andrew. Astronomers accidentally find a tiny galaxy that is nearly as old as the universe itself. The Independent. 2 February 2019. https://web.archive.org/web/20190202013609/https://www.independent.co.uk/news/science/hubble-nasa-esa-space-image-astronomers-galaxy-universe-old-as-fossil-a8758131.html. 2 February 2019. 1 February 2019. Together, those porperties led astronomers to classify it as what is called a dwarf spheroidal galaxy. [...] Because it is so distant from any other galaxies – and so has been left largely undisturbed – as well as its old age, the astronomers refer to Bedin 1 as a fossil from the beginning of the cosmos.. live.
  7. Web site: Carter. Jamie. The Milky Way Has A New Neighbor. Accidental Discovery As Ancient Galaxy Photobombs Hubble Telescope. Forbes. 1 February 2019. https://archive.today/20190201054934/https://www.forbes.com/. 1 February 2019. 31 January 2019. The astronomers that fortuitously discovered Bedin 1 were on a hunt for white dwarf stars in an effort to measure the age of NGC 6752 [...] it is roughly a thousand times dimmer than our Milky Way.. live.
  8. Web site: Bedin. Luigi. Jäger. Mathias. Hubble fortuitously discovers a new galaxy in the cosmic neighbourhood. ESA/Hubble. 1 February 2019. https://web.archive.org/web/20190201041001/https://www.spacetelescope.org/news/heic1903/. 1 February 2019. 31 January 2019. It lies about 30 million light-years from the Milky Way and 2 million light-years from the nearest plausible large galaxy host, NGC 6744. This makes it possibly the most isolated small dwarf galaxy discovered to date. [...] astronomers were able to infer that the galaxy is around 13 billion years old — nearly as old as the Universe itself.. live.
  9. Web site: Bedin. Luigi. Villard. Ray. Hubble Accidentally Discovers a New Galaxy in Cosmic Neighborhood. NASA Solar System Exploration. 1 February 2019. https://web.archive.org/web/20190201032113/https://solarsystem.nasa.gov/news/831/hubble-accidentally-discovers-a-new-galaxy-in-cosmic-neighborhood/. 1 February 2019. 31 January 2019. Because of its 13-billion-year-old age, and its isolation — which resulted in hardly any interaction with other galaxies — the dwarf is the astronomical equivalent of a living fossil from the early universe. [...] The science team's results will be published online January 31, 2019, in the Monthly Notices of the Royal Astronomical Society: Letters.. live.
  10. Web site: ESA/Hubble Information Centre. Hubble fortuitously discovers a new galaxy in the cosmic neighbourhood. Phys.org. 1 February 2019. https://web.archive.org/web/20190201050615/https://phys.org/news/2019-01-hubble-fortuitously-galaxy-cosmic-neighbourhood.html. 1 February 2019. 31 January 2019. The aim of their observations was to use these stars to measure the age of the globular cluster, [...] Bedin 1, which lies far behind the foreground globular cluster NGC 6752.. live.
  11. Web site: Bonnell. Jerry. Nemiroff. Robert J.. Robert J. Nemiroff. Globular Star Cluster NGC 6752. 12 August 2019. https://web.archive.org/web/20190812084443/https://apod.nasa.gov/apod/ap130705.html. 12 August 2019. 5 July 2013. Over 10 billion years old, NGC 6752 follows clusters Omega Centauri and 47 Tucanae as the third brightest globular in planet Earth's night sky.. live.
  12. Book: O'Meara, Stephen James. Deep-Sky Companions: Southern Gems. 8 April 2013. Cambridge University Press. 978-1-107-01501-2. 411. https://books.google.com/books?id=S5QIEKns33sC&pg=PA411. 113 The Starfish, The Windmill NGC 6752. At magnitude 5.4, it can be seen with the naked eye, and it ranks 5th among the globular clusters in total brightness..