May 2003

By Steve Stefanik

This month of May will host two spectacular celestial events, a transit of the planet Mercury across the face of the sun and a total lunar eclipse of the moon.

The first event will occur early in the morning as the sun rises in the east this coming Wednesday the 7^th. Because Mercury is the closest planet to the sun and never strays far from it, occasionally (14 times in the next 100 years) it passes in front of the sun from our perspective and can be seen as a tiny black "dot" silhouetted against the bright orange disk of the sun. There will be two problems in viewing the event however! The first is the danger in looking directly at the sun through a telescope, binoculars, or even with just your eyes. You will need a special filter to block out the sun’s harmful radiation. DO NOT USE photographic film negatives or anything less than number 7 welder’s glass! The second problem is that when the sun rises at approximately 5:30 a.m. EDT, the transit already be underway with only an hour remaining before "last contact" when it will move away from in front of the sun. Therefore, the sun will be at a very low altitude (less than 10 degrees) above the horizon, which means you will have to be at a location that has no hills, mountains, or buildings that will obscure the view. The seacoast will be the best vantage point.

The second event will occur on the evening of the 15^th when the full moon will past through the earth’s shadow resulting in a total lunar eclipse. The event will begin at approximately 9:00 p.m. EDT when the leading edge of the moon makes first contact with the penumbra (the lighter portion of the earth’s shadow). You’ll notice the moon partially darkened by a deep amber glow by 10:05 p.m. or so. At about 11:15 p.m., totality will start when the moon enters the umbra (the darker portion of the earth’s shadow) and reach totality at approximately 11:40 p.m. when it will be immersed in an eerie brownish red hue. Then the moon will begin move out of the umbra and into the penumbra once again at 12:05 a.m. ending totality. The remaining partial phase will fade back to normalcy ending at 2:15 a.m. the following morning.

So what is there to see the rest of the month? Plenty! The planets Juipter and Saturn are still visible in the western sky. Saturn is still in the constellation Taurus the bull shining at 0 magnitude. It sets at about 11:30 p.m. Jupiter is much higher in the sky and easy to spot at –2.0 magnitude to the right of the constellation Leo the lion and doesn’t set for a couple of hours after midnight.

The planet Mars is rising in the east about the time Jupiter is setting in the west. Look for the 0 magnitude golden globe among the dim stars of the constellation Capricorn.

The planets Uranus and Neptune are near Mars although you will need a telescope to spot them at +5.8 and +7.9 respectively.

Last to rise is the planet Venus low on the eastern horizon about an hour before the sun does. The good news is that you shouldn’t have any difficult spotting it because of it’s blazing –3.9 brilliance.