The result of scattered sunlight passing through the Earth's atmosphere and reaching the Moon.
by Antonello Medugno
A Total Lunar Eclipse in Our August Night Skies
If you missed the magnificent sights of the total lunar eclipse on the evening of Tuesday, August 28, then unfortunately you missed the best opportunity for many years to observe one of these dazzling natural displays. According to Mike Salway, an Australian astronomer and astrophotographer, the next total lunar eclipse will not be visible in Australia until December 2010.
What is a total lunar eclipse? It happens when the sun, moon and Earth form a straight line. Mr Salway explains, "A lunar eclipse can only happen during full moon, which is when the moon and sun are on opposite sides of the Earth.
As the sun shines on the Earth, it casts a shadow behind the Earth that extends into space. As the moon orbits the Earth, every so often the full moon will pass into that shadow, causing a lunar eclipse."
The recent lunar eclipse was visible to everyone who had the full moon in their hemisphere at the time. The eclipse only lasted about five hours from start to finish, meaning those in Asia, Africa and Europe would have missed the incredible sky show.
Mr Salway explains that for West Australians, the full moon rose at approximately 6 pm on Tuesday, August 28. At this time, the eclipse was already underway and the moon had just entered totality.
The total eclipse phase lasts approximately 90 minutes so while the moon was low on the horizon it took on a striking deep red colour. This was the effect of scattered sunlight passing through the Earths atmosphere and then hitting the Moon.
Mr Salway says, "The eastern cities [Brisbane, Melbourne, Hobart and Sydney] received the best views only because they saw the eclipse in its entirety, whereas for the cities in the west, the eclipse was already underway when the moon rose.
"This total lunar eclipse was our best view in years. It was at a perfect time of night, early in the evening, when families and groups could get together to observe the eclipse".
Total lunar eclipses happen more frequently than solar eclipses, and when viewing you do not need any special filters as they are completely safe to observe with the unaided eye. Iif you missed the eclipse this time, make a note to be around for the next one in 2010.
Mr Salway is also the founder of Ice In Space.
