All Sky Automated Survey for SuperNovae

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All Sky Automated Survey for SuperNovae
Alternative namesASAS-SN
Website www.astronomy.ohio-state.edu/~assassin/

The All Sky Automated Survey for SuperNovae (ASAS-SN) is an automated program to search for new supernovae and other astronomical transients, headed by astronomers from the Ohio State University, including Christopher Kochanek and Krzysztof Stanek. It has 20 robotic telescopes in both the northern and southern hemispheres. It can survey the entire sky approximately once every day. [1]

Initially, there were four ASAS-SN telescopes[ clarification needed ] at Haleakala and another four at Cerro Tololo, a Las Cumbres Observatory site. Twelve more telescopes were deployed in 2017 in Chile, South Africa and Texas, with funds from the Gordon and Betty Moore Foundation, the Ohio State University, the Mount Cuba Astronomical Foundation, China, Chile, Denmark, and Germany. All the telescopes (Nikon telephoto 400mm/F2.8 lenses) have a diameter of 14 cm and ProLine PL230 CCD cameras. The pixel resolution in the cameras is 7.8 arc seconds, so follow-up observations on other telescopes are usually required to get a more accurate location. [2]

The main goal of the project is to look for bright supernovae, and its discoveries have included the most powerful supernova event ever discovered, ASASSN-15lh. However, other transient objects are frequently discovered, including nearby tidal disruption events (TDEs) (e.g., ASASSN-19bt), Galactic novae (e.g., ASASSN-16kt, ASASSN-16ma, and ASASSN-18fv), cataclysmic variables, and stellar flares, including several of the largest flares ever seen. In July 2017 ASAS-SN discovered its first comet, ASASSN1, and in July 2019 it provided crucial data for the near-Earth asteroid 2019 OK. It can detect new objects with magnitudes between 18 and 8. [2]

Objects discovered receive designations starting with ASASSN followed by a dash, a two digit year and letters, for example ASASSN-19bt. [3]

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<span class="mw-page-title-main">V5856 Sagittarii</span> Nova that occurred in 2016

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<span class="mw-page-title-main">V407 Lupi</span> Nova that occurred in 2016

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Christopher Kochanek is an American astronomer. He works in the fields of cosmology, gravitational lensing, and supernovae. Kochanek currently is an Ohio Eminent Scholar at Ohio State University as well as an Elected Fellow of the American Association for the Advancement of Science.

<span class="mw-page-title-main">C/2017 O1 (ASASSN)</span> Comet

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<span class="mw-page-title-main">V906 Carinae</span> 2018 nova that occurred in the constellation Carina

V906 Carinae, also known as Nova Carinae 2018, was a nova in the Milky Way galaxy which appeared in the constellation Carina, near the 5th magnitude star HD 92063. It was discovered on images taken on 20.32 March 2018 by the All Sky Automated Survey for SuperNovae (ASAS-SN] telescope at the Cerro Tololo Inter-American Observatory. The ASAS-SN group assigned the name ASASSN-18fv to the object. The discovery image was saturated, allowing researchers to determine only that the object was brighter than apparent magnitude 10. An earlier image obtained by ASAS-SN on 26.32 March 2018 showed the nova was a magnitude ~10.4 object at that time, and the object was not detected on ASAS-SN images taken on 15.34 March 2018 and earlier.

<span class="mw-page-title-main">SN 2018cow</span> Supernova event of June 2018 in the constellation Hercules

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Krzysztof Stanek is a Polish observational astrophysicist and Professor and University Distinguished Scholar at Ohio State University. He was named a University Distinguished Scholar in 2018. His research focus is on the explosive deaths of massive stars.

An Intermediate Luminosity Optical Transient (ILOT) is an astronomical object which undergoes an optically detectable explosive event with an absolute magnitude (M) brighter than a classical nova (M ~ -8) but fainter than that of a supernova (M ~ -17). That nine magnitude range corresponds to a factor of nearly 4000 in luminosity, so the ILOT class may include a wide variety of objects. The term ILOT first appeared in a 2009 paper discussing the nova-like event NGC 300 OT2008-1. As the term has gained more widespread use, it has begun to be applied to some objects like KjPn 8 and CK Vulpeculae for which no transient event has been observed, but which may have been dramatically affected by an ILOT event in the past. The number of ILOTs known is expected to increase substantially when the Vera C. Rubin Observatory becomes operational.

References

  1. Dong, S.; Shappee, B. J.; Prieto, J. L.; Jha, S. W.; Stanek, K. Z.; Holoien, T. W.- S.; Kochanek, C. S.; Thompson, T. A.; Morrell, N.; Thompson, I. B.; et al. (January 15, 2016). "ASASSN-15lh: A highly super-luminous supernova". Science . 351 (6270): 257–260. arXiv: 1507.03010 . Bibcode:2016Sci...351..257D. doi:10.1126/science.aac9613. PMID   26816375. S2CID   31444274.
  2. 1 2 Holoien, Tom; Stanek, Kris (5 January 2016). "ASAS-SN's (Assassin's) Homepage". www.astronomy.ohio-state.edu. Retrieved 19 January 2016.
  3. Thomas W.-S. Holoien and 22 others Astrophysical Journal (September 26, 2019) Discovery and Early Evolution of ASASSN-19bt, the First TDE Detected by TESS Transiting Exoplanet Survey Satellite