The Zwicky Transient Facility (ZTF, obs. code: I41) is a wide-field sky

astronomical survey An astronomical survey is a general celestial cartography, map or astrophotography, image of a region of the sky (or of the whole sky) that lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of image ...

using a new camera attached to the

Samuel Oschin Telescope The Samuel Oschin telescope (), also called the Oschin Schmidt, is a Schmidt camera at the Palomar Observatory in northern San Diego County, California, United States. It consists of a Schmidt corrector plate and a (f/2.5) mirror. The instrumen ...

Palomar Observatory The Palomar Observatory is an astronomical research observatory in the Palomar Mountains of San Diego County, California, United States. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observat ...

San Diego County, California San Diego County (), officially the County of San Diego, is a county (United States), county in the southwest corner of the U.S. state of California, north to its Mexico-United States border, border with Mexico. As of the 2020 United States Cen ...

, United States. Commissioned in 2018, it supersedes the (Intermediate)

Palomar Transient Factory The Palomar Transient Factory (PTF, obs. code: I41), was an astronomical survey using a wide-field survey camera designed to search for optical transient and variable sources such as variable stars, supernovae, asteroids and comets. The projec ...

(2009–2017) that used the same observatory code. It is named after the

Swiss Swiss most commonly refers to: * the adjectival form of Switzerland * Swiss people Swiss may also refer to: Places * Swiss, Missouri * Swiss, North Carolina * Swiss, West Virginia * Swiss, Wisconsin Other uses * Swiss Café, an old café located ...

astronomer

Fritz Zwicky Fritz Zwicky (; ; February 14, 1898 – February 8, 1974) was a Swiss astronomer. He worked most of his life at the California Institute of Technology in the United States of America, where he made many important contributions in theoretical an ...

Description

Observing in visible and infrared wavelengths, the Zwicky Transient Facility is designed to detect transient objects that rapidly change in brightness, for example

supernovae A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion. The original ob ...

gamma ray burst In gamma-ray astronomy, gamma-ray bursts (GRBs) are extremely energetic events occurring in distant galaxies which represent the brightest and most powerful class of explosion in the universe. These extreme electromagnetic emissions are second ...

s, and collision between two

neutron star A neutron star is the gravitationally collapsed Stellar core, core of a massive supergiant star. It results from the supernova explosion of a stellar evolution#Massive star, massive star—combined with gravitational collapse—that compresses ...

s, and moving objects like

comet A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

s and

asteroid An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

s. The new camera is made of 16 CCDs 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 the

Milky Way The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galax ...

twice each night to a limiting

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

of 20.5 (r band, 5σ). The amount of data produced by ZTF is expected to be ten times larger than its predecessor, the Intermediate Palomar Transient Factory. ZTF's large data will allow it to act as a prototype for the Vera C. Rubin Observatory (formerly Large Synoptic Survey Telescope) that is expected to be in full operation in 2024 and will accumulate ten times more data than ZTF. First light was recorded of an area in the constellation Orion on November 1, 2017. The first confirmed findings from the ZTF project were reported on 7 February 2018, with the discovery of 2018 CL, a small

near-Earth asteroid A near-Earth object (NEO) is any small Solar System body orbiting the Sun whose closest approach to the Sun (perihelion) is less than 1.3 times the Earth–Sun distance (astronomical unit, AU). This definition applies to the object's orbit aro ...

Discoveries

* On 9 May 2019, ZTF discovered its first comet, C/2019 J2 (Palomar), a long-period comet. * A search of the ZTF archive identified images of the interstellar comet

2I/Borisov 2I/Borisov, originally designated C/2019 Q4 (Borisov), is the first observed rogue comet and the second observed interstellar interloper after ʻOumuamua. It was discovered by the Crimean Amateur astronomy, amateur astronomer and telescope make ...

as early as December 13, 2018, extending observations back eight months. *

594913 ꞌAylóꞌchaxnim 594913 ꞌAylóꞌchaxnim ( provisional designation ) is a large near-Earth asteroid discovered by the Zwicky Transient Facility on 4 January 2020. It is the first asteroid discovered to have an orbit completely within Venus's orbit, and is thu ...

, the first asteroid discovered whose orbit is entirely within the orbit of Venus, was discovered by ZTF during its Twilight Survey. * A search of ZTF's images identified

cataclysmic variable star In astronomy, cataclysmic variable stars (CVs) are stars which irregularly increase in brightness by a large factor, then drop back down to a quiescent state. They were initially called novae (), since those with an outburst brightness visible t ...

ZTF J1813+4251 The Zwicky Transient Facility (ZTF, List of observatory codes, obs. code: IAU code#I41, I41) is a wide-field sky astronomical survey using a new camera attached to the Samuel Oschin Telescope at Palomar Observatory in San Diego County, Californi ...

, a binary with a period of under 1 hour. *

AT2021lwx AT 2021lwx (also known as ZTF20abrbeie or "Scary Barbie") is the most energetic non-quasar optical transient astronomical event ever observed, with a peak luminosity of 7 × 1045 erg per second (erg s−1) and a total radiated energy between 9. ...

, a long-lasting high-energy transient with a redshift of 0.9945, was discovered on 13 April 2021. * A very bright

tidal disruption event A tidal disruption event (TDE) is a time-domain astronomy, transient astronomical source produced when a star passes so close to a supermassive black hole (SMBH) that it is pulled apart by the black hole's tidal force. The star undergoes spaghett ...

called AT2022cmc with a

redshift In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and increase in frequency and e ...

of 1.19325, among the brightest astronomical events ever observed. * Comet C/2022 E3 (ZTF), which reached naked eye visibility in early 2023.

References

{{Portal bar, Astronomy, Stars, Outer space, Solar System Astronomical surveys Palomar Observatory

Description

Discoveries

See also

References