T Boötis is believed to have been a

nova A nova ( novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", Latin for "new") that slowly fades over weeks or months. All observed novae involve white ...

. It was observed by only one person, Joseph Baxendell, on 9, 11 and 22 April 1860, but has not been seen since. It is located less than half a degree from

Arcturus , - bgcolor="#FFFAFA" , Note (category: variability): , , H and K emission vary. Arcturus is a red giant star in the Northern celestial hemisphere, northern constellation of Boötes, and the brightest star in the constellation. It ha ...

in the

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

Boötes Boötes ( ) is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from , which comes from 'herder, herdsman' or 'plowman' (literally, 'o ...

and was at magnitude 9.75 when first seen, and magnitude 12.8 when last seen. Other astronomers, including Friedrich Winnecke,

Edward Charles Pickering Edward Charles Pickering (July 19, 1846 – February 3, 1919) was an American astronomer and physicist and the older brother of William Henry Pickering. Along with Carl Vogel, Pickering discovered the first spectroscopic binary stars. He wrote ' ...

Ernst Hartwig Carl Ernst Albrecht Hartwig (14 January 1851 in Frankfurt – 3 May 1923 in Bamberg) was a German astronomer. On 20 August 1885, Hartwig discovered a new star, SN 1885A (S Andromedae), in the Andromeda Galaxy, which was the first supernova ...

and

Ernst Zinner Ernst Zinner (2 February 1886 in Goldberg, Silesia – 30 August 1970) was a German astronomer and noted historian of astronomy. He was a director of the observatory at Bamberg. His major work was on the diffusion of Copernican ideas. Duri ...

looked for a star in this location without success. Despite being usually referred to as a nova, it had characteristics that set it apart from other novae: an amplitude of at least 7 magnitudes, an unusually rapid decline in brightness and a location unusually far from the

Galactic plane The galactic plane is the plane (geometry), plane on which the majority of a disk-shaped galaxy's mass lies. The directions perpendicular to the galactic plane point to the galactic poles. In actual usage, the terms ''galactic plane'' and ''galac ...

Joseph Ashbrook Joseph Ashbrook (April 4, 1918 – August 4, 1980) was an American astronomer. Biography Ashbrook was born in Philadelphia, Pennsylvania. He received a doctorate from Harvard University in 1947 and taught at Yale University from 1946 to 1950, and ...

suggested in 1953 that it may be a recurrent nova which has been observed only once.

References

Novae Boötes 1860 in science Bootis, T {{var-star-stub