astronomy Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...

, first light is the first use of a

telescope A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to obse ...

(or, in general, a new instrument) to take an astronomical image after it has been constructed. This is often not the first viewing using the telescope; optical tests will probably have been performed to adjust the components.

Characteristics

The first light image is normally of little scientific interest and is of poor quality, since the various telescope elements are yet to be adjusted for optimum efficiency. Despite this, a first light is always a moment of great excitement, both for the people who design and build the telescope and for the astronomical community, who may have anticipated the moment for many years while the telescope was under construction. A well-known and spectacular astronomical object is usually chosen as a subject.

Historical examples

The famous Hale Telescope of Palomar Observatory saw first light on 26 January 1949, targeting NGC 2261 under the direction of American astronomer

Edwin Powell Hubble Edwin Powell Hubble (November 20, 1889 – September 28, 1953) was an American astronomer. He played a crucial role in establishing the fields of extragalactic astronomy and observational cosmology. Hubble proved that many objects previous ...

. The image was published in many magazines and is available on Caltech Archives. The Isaac Newton Telescope had two first lights: one in England in 1965 with its original mirror, and another in 1984 at La Palma island. The second first light was done with a video camera that showed the Crab Pulsar flashing. Elation at first light images by the

Hubble Space Telescope The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most vers ...

in 1990 soon gave way to initial disappointment when a flaw prevented adjustments for proper operation. The expected first light image quality was finally achieved after a 1993 servicing mission by Space Shuttle ''Endeavour''. The Large Binocular Telescope had its first light with a single primary mirror on 12 October 2005, which was a view of NGC 891. The second primary mirror was installed in January 2006 and became fully operational in January 2008. The

Gran Telescopio Canarias The Gran Telescopio Canarias (GranTeCan or GTC) is a reflecting telescope located at the Roque de los Muchachos Observatory on the island of La Palma, in the Canaries, Spain. It is the world's largest single-aperture optical telescope. Con ...

had a first light image of Tycho 1205081 on 14 July 2007. The IRIS solar space observatory achieved first light on 17 July 2013. The PI noted:

"The quality of images and spectra we are receiving from IRIS is amazing. This is just what we were hoping for ..."

On 4 February 2022, the first light viewed by the James Webb Space Telescope (JWST) was from the star

HD 84406 The James Webb Space Telescope (JWST) is a space telescope which conducts infrared astronomy. As the largest optical telescope in space, its high resolution and sensitivity allow it to view objects too old, distant, or faint for the Hubble ...

for the purpose of testing and aligning the focus of the telescope's 18 mirrors. On 11 February 2022. ''

The New York Times ''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid ...

'' reported that "first light" images from the James Webb Space Telescope were released - as well as a relate
NASA alignment video (2/11/2022; 3:00)
On 6 July 2022, NASA released a test image from the JWST's Fine Guidance Sensor. NASA released the first official JWST image on 11 July 2022. Later, in an official ceremony, the first collection of five JWST science images were released on Tuesday, 12 July 2022 (NASA-TV live; 10:30 am/et/usa).

Gallery

File:NGC 5317 (also NGC 5364).jpg, Very Large Telescope's wide field imager VIMOS takes its first light image of

NGC 5364 NGC 5364 is a grand design spiral galaxy located 54.5 million light years away in the constellation Virgo. It is inclined to the line of sight from the Earth at an angle of 47° along a position angle of 25°. It is a member of the NGC 5364 ...

. File:Hubble First Light, First Released Image (STScI-1990-04a).png,

's first light with its impaired WFPC, 1990 File:Tarantula Nebula TRAPPIST.jpg, First light of the Tarantula Nebula by TRAPPIST File:WISPR first light image.png, First light of

WISPR The Wide-Field Imager for Solar Probe (WISPR) is an imaging instrument of the '' Parker Solar Probe'' mission to the Sun, launched in August 2018. Imaging targets include visible light images of the corona, solar wind, shocks, solar ejecta, etc. De ...

on the Parker Solar Probe, September 2018

References

{{reflist, 2 Telescopes Astronomical imaging