Wide-field sky survey at Palomar Observatory
TheZwicky Transient Facility (ZTF,obs. code :I41 ) is a wide-field skyastronomical survey using a new camera attached to theSamuel Oschin Telescope atPalomar Observatory inSan Diego County, California , United States. Commissioned in 2018, it supersedes the (Intermediate)Palomar Transient Factory (2009–2017) that used the same observatory code. It is named after theSwiss astronomerFritz Zwicky .[ 1]
The Samuel Oschin Telescope, used for the survey Observing in visible and infrared wavelengths,[ 2] transient objects that rapidly change in brightness, for examplesupernovae ,gamma ray bursts , and collision between twoneutron stars , and moving objects likecomets andasteroids .
The new camera is made of 16CCDs of 6144×6160 pixels each, enabling each exposure to cover an area of 47 square degrees. The Zwicky Transient Facility is designed to image the entire northern sky in three nights and scan the plane of theMilky Way twice each night to a limitingmagnitude of 20.5 (r band, 5σ).[ 3] [ 4]
The amount of data produced by ZTF is expected to be ten times larger than its predecessor, the Intermediate Palomar Transient Factory.[ 5] Vera C. Rubin Observatory (formerly Large Synoptic Survey Telescope) that is expected to be in full operation in late 2025 and will accumulate ten times more data than ZTF.[ 3] [ 1]
First light was recorded of an area in the constellationOrion on November 1, 2017.[ 6] [ 7] [ 8]
The first confirmed findings from the ZTF project were reported on 7 February 2018,[ 9] 2018 CL , a smallnear-Earth asteroid .[ 10]
On 9 May 2019, ZTF discovered its first comet, C/2019 J2 (Palomar), a long-period comet.[ 11] A search of the ZTF archive identified images of theinterstellar comet 2I/Borisov as early as December 13, 2018, extending observations back eight months.[ 12] [ 13] 594913 ꞌAylóꞌchaxnim , the first asteroid discovered whose orbit is entirely within the orbit of Venus, was discovered by ZTF during its Twilight Survey.[ 14] A search of ZTF's images identifiedcataclysmic variable star ZTF J1813+4251 , a binary with a period of under 1 hour.[ 15] AT2021lwx , a long-lasting high-energy transient with a redshift of 0.9945, was discovered on 13 April 2021.[ 16] [ 17] [ 18] A very brighttidal disruption event calledAT2022cmc with aredshift of 1.19325, among the brightest astronomical events ever observed.[ 19] [ 20] CometC/2022 E3 (ZTF) , which reached naked eye visibility in early 2023. ^a b "Zwicky Transient Facility Opens Its Eyes to the Volatile cosmos" .Zwicky Transient Facility . November 14, 2017. Archived fromthe original on November 11, 2021. RetrievedApril 13, 2018 .^ Bellm, Eric; et al. (2019)."The Zwicky Transient Facility: System Overview, Performance, and First Results" .Publications of the Astronomical Society of the Pacific .131 (995): 018002.arXiv :1902.01932 Bibcode :2019PASP..131a8002B .doi :10.1088/1538-3873/aaecbe S2CID 119410793 . ^a b Bellm, Eric; Kulkarni, Shrinivas (2017-03-02). "The unblinking eye on the sky".Nature Astronomy .1 (3): 0071.arXiv :1705.10052 Bibcode :2017NatAs...1E..71B .doi :10.1038/s41550-017-0071 .ISSN 2397-3366 .S2CID 119365778 . ^ Smith, Roger M.; Dekany, Richard G.; Bebek, Christopher; Bellm, Eric; Bui, Khanh; Cromer, John; Gardner, Paul; Hoff, Matthew; Kaye, Stephen (2014-07-14)."The Zwicky transient facility observing system" (PDF) . In Ramsay, Suzanne K; McLean, Ian S; Takami, Hideki (eds.).Ground-based and Airborne Instrumentation for Astronomy V Bibcode :2014SPIE.9147E..79S .doi :10.1117/12.2070014 .S2CID 9106668 . ^ Cao, Yi; Nugent, Peter E.;Kasliwal, Mansi M. (2016). "Intermediate Palomar Transient Factory: Realtime Image Subtraction Pipeline".Publications of the Astronomical Society of the Pacific .128 (969) 114502.arXiv :1608.01006 Bibcode :2016PASP..128k4502C .doi :10.1088/1538-3873/128/969/114502 .S2CID 39571681 . ^ Clery, Daniel (2017-11-13)."New California telescope aims to catch quickly moving celestial events" .Science . Retrieved14 November 2017 . ^ "The Zwicky Transient Facility" . The Palomar Observatory. Retrieved14 November 2017 .^ Boyle, Alan (14 November 2017)."Super-wide-angle Zwicky Transient Facility celebrates 'first light' with help from UW" .GeekWire . Retrieved14 November 2017 . ^ Kulkarni, S.R.; et al. (7 February 2018)."The Zwicky Transient Facility (ZTF) begins - ATel #11266" .Astronomer's Telegram . Retrieved8 February 2018 . ^ Ye, Quan-Zhi; et al. (8 February 2018)."First Discovery of a Small Near Earth Asteroid with ZTF (2018 CL) - ATel #11274" .Astronomer's Telegram . Retrieved8 February 2018 . ^ Williams, Gareth V."MPEC 2019-J123: COMET C/2019 J2 (Palomar)" .Minor Planet Center . Retrieved3 November 2019 . ^ Wayt Gibbs, W."Alien comets may be common, object from beyond Solar System suggests" .Science . Retrieved3 November 2019 . ^ Williams, Gareth V."MPEC 2019-V34: COMET 2I/Borisov" .Minor Planet Center . Retrieved3 November 2019 . ^ Bolin, Bryce T; Ahumada, T; van Dokkum, P; Fremling, C; Granvik, M; Hardegree-Ullman, K K; Harikane, Y; Purdum, J N; Serabyn, E; Southworth, J; Zhai, C (30 September 2022)."The discovery and characterization of (594913) 'Ayló'chaxnim, a kilometre sized asteroid inside the orbit of Venus" .Monthly Notices of the Royal Astronomical Society: Letters .517 (1):L49 – L54 .arXiv :2208.07253 doi :10.1093/mnrasl/slac089 ^ "Astronomers find a "cataclysmic" pair of stars with the shortest orbit yet" .MIT News | Massachusetts Institute of Technology . October 5, 2022.^ Subrayan, Bhagya M.; Milisavljevic, Dan; Chornock, Ryan; Margutti, Raffaella; Alexander, Kate D.; Ramakrishnan, Vandana; Duffell, Paul C.; Dickinson, Danielle A.; Lee, Kyoung-Soo; Giannios, Dimitrios; Lentner, Geoffery; Linvill, Mark; Garretson, Braden; Graham, Matthew J.; Stern, Daniel (2023-05-01)."Scary Barbie: An Extremely Energetic, Long-duration Tidal Disruption Event Candidate without a Detected Host Galaxy at z = 0.995" .The Astrophysical Journal Letters .948 (2): L19.arXiv :2302.10932 Bibcode :2023ApJ...948L..19S .doi :10.3847/2041-8213/accf1a ISSN 2041-8205 .S2CID 257079239 . ^ Wiseman, p.; Wang, Y.; Hönig, S.; Castero-Segura, N.; Clark, P.; Frohmaier, C.; Fulton, M. D.; Leloudas, G.; Middleton, M.; Müller-Bravo, T. E.; Mummery, A.; Pursiainen, M; Smartt, S. J.; Smith, K.; Sullivan, M. (July 2023)."Multiwavelength observations of the extraordinary accretion event AT2021lwx" .Monthly Notices of the Royal Astronomical Society 522 (3):3992– 4002.arXiv :2303.04412 doi :10.1093/mnras/stad1000 ^ Overbye, Dennis (12 May 2023)."The Biggest Explosion in the Cosmos Just Keeps Going - For three years, telescopes have monitored "one of the most luminous" events ever: a supermassive black hole consuming a gigantic cloud of interstellar gas" .The New York Times Archived from the original on 12 May 2023. Retrieved13 May 2023 .^ Goodwin, Adelle; Miller-Jones, James (30 November 2022)."Astronomers witness the dying flare of a star torn apart by a black hole halfway across the Universe" .The Conversation . Retrieved2022-12-27 . ^ Jonathan O'Callaghan (Nov 30, 2022)."Star ripped up by black hole is one of the brightest things ever seen" .New Scientist . 
