Showing posts with label amateur astronomy. Show all posts
Showing posts with label amateur astronomy. Show all posts

Saturday, October 20, 2007

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.

Saturday, November 18, 2006

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.