An Evening of Astronomical Importance

This Wednesday evening, while nearly three hundred Brentwood staff and students are returning to campus from a day of skiing, a rare and spectacular event will be well underway in the night sky above them. Starting around 5:40 p.m. (PST) on Wednesday February 20th, the full moon will start to slip into Earth's penumbra and a total lunar eclipse will begin. Lunar eclipses occur when the Moon passes into the shadow of the Earth. The Sun's light is partially blocked in the region called the penumbra, while fully blocked in another called the umbra. What makes a total lunar eclipse special is that the Moon passes through the umbra causing the Moon to nearly disappear from our sight. This will occur around 7:30 p.m. this Wednesday and the Moon will remain in the shadow of the Earth until just after 9 p.m. Lunar eclipses only occur when the Moon is full. However, they do not occur monthly as full moons do, which is precisely what makes this event special! The most recent total eclipse was August 28th, 2007 and the next lunar eclipse is not until December 21, 2010. Of course, to see the Moon and the lunar eclipse, it must be night at the point of observation and the skies must be clear. The moment when the Moon begins to slip into the Earth's penumbra can be identified by a colour change in the Moon from white/yellow to a red/brown. When the Moon changes from this red/brown colour to black, the Moon is moving into the Earth's umbra and the total eclipse in underway. I know what I will be doing this Wednesday evening; I hope you enjoy the astronomical event that will be taking place in your own backyard!
Josie Herman