Comet Holmes from OAN-SPM

Comet Holmes is an old folk for astronomers, discovered in 1892 and with a period of 5.9 years, it was discovered in an outburst during which the comet brigthened to a magnitude around 4-5.

A similar outburst happened last october, from magnitude 17 to 2.5! It is still visible at the dusk (or dawn) if you look at Perseus, maybe some binoculars will be necesary. I won't delve further into it because there are many posts about it in the blogosphere (1)(2)(3), rather I'll show you a nice pic of this comet.

Use this sky chart to look for Comet Holmes, it depicts the sky at a latitude adequate for most of North America and Europe.

Alan Watson, an astronomer at Centro de Radiastronomía y Astrofísica, UNAM was at OAN-SPM (National Astronomical Observatory at San Pedro Martir), and used the 1.5 meter telescope to take this nice picture of comet Holmes in the R band (meaning light was filtered to only allow "red" light arrive the detectors).

The exposition time was 10 seconds. Look at the displacement between the core and the coma.

Halley's debris

During the year, earth's orbit crosses the paths of hubris left behind by comets. When this debris enters the atmosphere it is heated by friction and it's temperature raises dramatically making them quite easy to spot, this are the so called shooting stars.

When the earth crosses a dense stream then the number of shooting stars (usually close to one per hour in the whole sky) meteor showers occur. Some well known meteor showers are the Perseids and the Leonids (usually boring, the Leonids can produce the most spectacular meteor showers evey 33 years including the meteor shower of 1833, usually considered the most spectacular ever).

Tomorrow's night (October 21-22) the Orionids will reach their peak, in the north you can expect 20 meteors per hour and 40 in the south.

Use this starmap (from meteorshowersonline) to watch the orionids, the stream of meteors will look as emerging from a radiant, the radiant is quite close to red bright star Betelgeuse.

Remember that this means 20 meteors in the full sky, and to be honest this shower isn't as reliable as the Perseids, nonetheless it is a nice weekend activity.

The source of the Orionids stream is the famous Halley's comet, so you are actually watching little pieces from this comet as they enter the earth, quite amazing if you think about it, there are even missions where high altitude planes collect this comet dust.

Watch for comet McNaught, today!

Comet McNaught has brightened this week to the point it is readily observable, even in large cities! If you are living at northern latitutes and have a clear southwestern sky you can try to watch it, it might be a very nice sight. Depending on your latitude you can watch it up to the friday or saturday.

The comet should be very low, close to the horizon, at 15-20 degrees from Venus (depending of your latitude). For more detailed instructions go to SkyTonight.com site, they also have a nice photo gallery.

Watch for earth-gazers

If you are living in New England and the eastward parts of New York State and Quebec watch out for the leonids. This are particles from the comet Temple-Tuttle and are usually a meager show, but every 33 years the Earth enters in a particullary rich part of the stream, this actually happened in the 1998-2002 period, with the 2001 leonids beeing the most remarkable meteor shower in decades, so we are out of the "sweet spot".

Despite that, today (saturday 18) the earth passes through a narrow and dense part of the filament, if you live in the zones mentioned above then at around 11:45 pm east time (04:45 UT) you can expect a nice show, Leo won't be quite high in the sky so don't expect a literal rainfall of the meteors, the nice thing about tonight's meteor shower is that the meteors will enter the atmosphere at a low angle producing very long trails known as "earth gazers". If you are lucky enough to watch this from one of this places please leave a comment!

So, stop reading this and look in the direction of the Leo constellation, now! If you don't know where to look you can use the skycharts at SkyTonight.com.Look for more details (inclyding a map of the trail) here, if you can't see the country in the map (like me) you are out of luck.