What is a meteor?
A meteor is a small particle which enters the Earth's atmosphere
and burns up before reaching the Earth. Most meteors are no larger
than a grain of sand although the most spectacular ones will be
small rocks. Most of the debris that becomes meteors is believed
to have come from Comets. Meteors, also known as shooting stars,
appear as bright white or blue streaks in the sky as they burn up
from the heat of friction from the atmosphere. Occasionally they
appear as other colours, notably orange or yellow and sometimes
red or green. Meteors travel at around 70 kilometres per second
(almost 160,000 miles per hour). Most meteors completely burn up
at around 70 miles from the Earth and they are often visible for
less than a second.
One of the most amazing scenes I have ever witnessed was the Leonids
storm of 1998. Where one could expect to see thirty or forty meteors
on a good night, (4 or 5 of which might be classed as spectacular),
on 16th November 1998 at around one o'clock in the morning I was
stunned by the frequency and beauty of the storm I witnessed from
the field behind my house. I saw around 200 meteors within an hour
and of those about 50 were superb. If you are lucky enough to see
a really bright meteor with a long tail you too will be hooked.
The Leonids shower is at its best every 33 years so you might have quite a wait for the next really spectacular show.
What is the difference between a meteor and a
A meteorite is a particle large enough to survive the passage through
the atmosphere. Every year many thousands of meteorites hit the
Earth. Because most of the Earth's surface is covered by water or
uninhabited wilderness or farmland they do not often come to the
attention of man.
What do I need to see meteors?
No special equipment is needed to watch meteors successfully. Telescopes
and binoculars are useless because you need to be scanning as much
of the sky as possible. The best technique is to find an open space
with good all round visibility, place a large blanket on the ground
and lie down flat on your back. Move your eyes around the sky watching
for the familiar streak of light from a meteor. Remember to wear
warm clothes, a hat and gloves may also be worthwhile. The best
nights for meteor spotting are when the sky is clearest - unfortunately
these also tend to be the coldest nights.
How is it possible to predict when meteors will
Because the Earth travels round the Sun once per year, we pass through
the same areas of debris on the same date every twelve months. It
is therefore possible to say exactly when a good meteor shower is
likely to occur. Meteor showers are rated - you will see an nnn
per hour figure in our diary listing. This is more accurately described
as ZHR (Zenithal Hourly Rate) which is the number of meteors which
could be seen by someone in ideal conditions. A figure of over 25
per hour is worth taking a look outside and around 100 per hour
is worth a special effort.
What if I don't see anything?
Don't give up - sometimes it is just because the predictions are
wrong. Alternatively it may just be the wrong time of the night
- just as the moon rises at different times of the night so do the
meteor storms. The right part of the night sky may not be visible
from your area when you are ready to go outside and look so be patient.
The other common problems are cloudy skies or a bright moon.
If there are no meteor showers due then find out when to look out for the International Space Station (ISS) in Swallowcliffe. The space station is the brightest satellite in the skies and orbits the Earth every hour and a half (17,500 mph) at a height of about 220 miles (it varies). The structure is 108 metres wide (the same as the wingspan of two Jumbo Jets side by side) and when completed in 2010 will weigh about 400,000 Kg (441 tons).
One of the biggest problems for meteor watchers is light pollution.
In the UK there are only three decent sized areas which are relatively
free of light pollution. These are Scotland, Wales and the South
West (particularly Salisbury Plain and surrounding area). There
is also a moderately unpolluted area in East Anglia. Visit the Campaign
for Dark Skies web site for more information. To see how bad
light pollution is take a look at this satellite
image of the UK at night or this light
pollution map of Europe.
When do the best meteor showers occur?
July 17 - Aug 24
Nov 14 - 20
20 - 100+
Dec 7 - 17
View the Swallowcliffe
diary for the latest activities
Other interesting stuff:
By: Chris Stanbury
How Satellites work - http://science.howstuffworks.com/satellite3.htm
International Space Station visibility - http://www.heavens-above.com
More about Meteors - http://www.cbc.ca/news/background/meteors
Even more about Meteors - http://www.astronomy.com/asy/default.aspx?c=ss&id=77