The Carlisle Mosquito Online

Friday, January 7, 2005


Comet Machholz: naked-eye comet ?

By the time you read this, Comet Machholz, discovered in August 2004, will be ideally positioned for viewing high in the sky to the south. On January 7, it passes within two degrees west of the Pleiades (the full moon is 1/2 degree in diameter) so it should be easy to locate with a pair of binoculars. It crosses the meridian (due south) about 9 p.m. at an elevation of about 70 degrees. This also is the date when it is predicted to be the brightest and there is no moon. Of course any other time during the evening when you can find the Pleiades the comet should be visible. So, rather uniquely for sky events, all the conditions favorable for viewing come together in early January, weather permitting.

If you miss it one night, try on following nights as it remains high in the sky and dims only slowly in January and February. After January 7-8, Machholz moves away from the Pleiades, so it may be more difficult to find. As an aid the table below gives the approximate times when it crosses the meridian and its elevation at crossing.

Date Time Elevation

Jan. 9 9:00 73 degrees
Jan. 15 8:25 85
Jan. 20 7:50 94*
Jan. 25 7:20 102*
Jan. 30 7:00 108*

* Now over the zenith and to the north.

Binoculars or a low-power telescope would be the perfect way to observe the comet. So called "night glasses," 7x50 binoculars, are the binoculars of choice because they allow the most light to be gathered into the eyes. But daytime binoculars should work well also; I found the comet on December 17 and January 1 with a pair of 12x36 binoculars but was unable to see it with my unaided eyes. No tail was seen, just a fuzzy ball.

Whether or not you will be able to see the comet will depend upon how dark the sky is, and usually in Carlisle we are bothered by skylight from the surrounding towns.

See for further information and photos showing a blue gas tail and yellowish dust tail.

2005 The Carlisle Mosquito