Comet West

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There is another long-period comet West: C/1978 A1 (a.k.a. 1977 IX, 1978a).

**C/1975 V1 (West)**
Discovery

Discovered by:	Richard M. West
Discovery date:	August 10, 1975
Alternate designations:	C/1975 V1, 1976 VI, 1975n
Orbital characteristics ^A
Epoch:	2442840,5
Aphelion distance:	13560 AU
Perihelion distance:	0.58 AU
Semi-major axis:	6.780,20 AU
Eccentricity:	0,99997
Orbital period:	558306,4201 a
Inclination:	43,0664°
Last perihelion:	February 25, 1976
Next perihelion:	560.282

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 during 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 559,000 years.

[edit] Breakup

During the comet's 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 1970s. 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. When observed, many were stunned, but none more so than the discoverer, Richard Martin West. The comet broke into pieces when some distance from the sun. It exploded into four pieces, and those were scattered. Later, two pieces were spotted, and studied intently by astronomers.

[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" uses the Roman numeral VI = 6, while "C/1975 V1" is the letter V and the number 1).