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Thu, 31 Jan 2008 - Latest news about Comet 17P Holmes

Major comet outburst

A faint comet has amazed observers by brightening up by one million times greater than normal, bringing it well up to naked-eye visibility. The comet, known as P/Holmes, was expected to be about 17th magnitude on 24 October when a Spanish amateur, Juan Antonio HenrĂ­quez Santana, discovered that it had brightened up to 10th magnitude. During late October and November the comet was easily visible with the naked eye as a fuzzy star in Perseus. It should remain visible during January, if not with the unaided eye then with binoculars, though no one is really sure what it will do.

If you are unfamiliar with the sky, use the all-sky map below to locate Perseus, which is high up in the south at around 9 pm. The map is drawn for the UK but should apply throughout Europe and North America with minor differences. Perseus is visible throughout the night.


Here is a closeup of Perseus, with north at the top, with the comet's track marked throughout January:

Finder chart

Here is a photo of the same area taken on 2 January with a slightly different orientation. The comet is towards the bottom of the picture. Photo taken with Canon 10D camera, ISO 400, four undriven 8-sec exposures wth 50 mm f/1.8 lens combined.


Comet Holmes was discovered in 1892 when it underwent a similar outburst, followed by a subsequent decline in brightness. It is currently some 243 million km from Earth, and 368 million km from the Sun, which puts it between the orbits of Mars and Jupiter, but considerably above the ecliptic. For a 3D view of its orbit, click here.

The comet orbits the Sun every 6.88 years, and last came close to the Sun on 4 May 2007.

Observations should be sent to the Comet Section director, Jonathan Shanklin.


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