Comet West

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Comet West formally designated C/1975 V1, 1976 VI, and 1975n, was a spectacular comet, sometimes considered to qualify for the status of "great comet".

It was discovered photographically by Richard M. West, of the European Southern Observatory, on August 10, 1975 and reached peak brightness in March 1976, attaining a brightness of -3 at perihelion. During peak brightness, observers reported that it was bright enough to study duing full daylight.

Comet West was what 1973's Comet Kohoutek should have been. Kohoutek was overhyped and underperforming, and West was the exact opposite. If anything, it was underhyped, because no one wanted to get burned again making ambitious predictions. As a result, Comet West was largely unheralded outside the astronomical community.

The comet has an estimated orbital period of 558,000 years.

[edit] Breakup

During the comet's first run into the inner solar system for the first time in 500,000 years, the nucleus of Comet West was observed to split into four fragments as it passed within 30 million km. of the sun.

The first report of the split came around 7 March 1976 12:30UT, when reports were received that the comet had broken into two pieces. These two fragments remained the only pieces until Steven O'Meara, using the 9-inch Harvard Refractor, reported that two additional fragments had formed on the morning of 18 March.

The breakup was one of very few comet breakups observed from historical times by the 1970's. Recently, comets Shoemaker-Levy 9, Schwassmann-Wachmann-3 (73/P), C/1999 S4 LINEAR, and 57/P du Toit-Neujmin-Delporte, have been observed to disintegrate.

[edit] Nomenclature

In the nomenclature of the time, it was known as Comet 1976 VI or Comet 1975n, but the modern nomenclature is C/1975 V1. (Note that "1976 VI" includes the Roman numeral VI = 6, while "C/1975 V1" is the letter V and the number 1).