Everything you always wanted to know about astronomy
August
By Bruce Dennis

Bruce Dennis is a retired science teacher from Haverling High School.

On April 26th, the world's largest airborne observatory, SOFIA, took off with its 98- inch telescope to fly above 98% of the watervapor-loaded atmosphere. This observatory is cleverly disguised as a Boeing 747 and will be tested for the next year. This will give us images similar to those we get from the Space Telescope, but it'll be easier to service and modify this telescope. In the meantime, let's look at the planets of our Solar System from our ground-based telescopes.

There will be a total Lunar eclipse on August 28th. This occurs when the Moon (which we only see by reflected light) passes into the Earth's shadow. It will probably be in the shadow for about an hour and a half - a long time for an eclipse. In the middle of the 90-minute eclipse period, the Moon will be very dark - very hard to see. More than half of the world's population will be able to witness this event - far more than have seen any other lunar eclipse in recorded history. Too bad that most of this event will occur during daylight hours for us. More on this in a few moments.

Jupiter, high in the South at Sunset, is the first 'star' to glow in the evening. It'll stop its Westward (retrograde) motion and start moving to the East. Use your binoculars to determine its changing position against the background stars. With your telescope, this is a good time to marvel at the gas bands of light and dark colors on the planet's surface.

About 1 AM, Mars will rise during the first couple weeks of August. During the next couple weeks of the month, Mars will rise about midnight. On the 7th, Mars passes closely to the Pleiades (7 Sisters). It is still very small in a telescope, but grows to more than twice its present size by December. Don't touch that dial! I'll keep you up-todate on the increasingly better views.

During the first few evenings of August, Venus (a bright beacon) is shining near the Western horizon, ready to set immediately after the Sun. During the rest of the month, Venus will be invisible to us - its on the near side of the Sun - below the horizon. By August's end, it'll be a morning 'star', rising in the East at Sunrise. It'll be a thin crescent, telescopically visible just before Sunrise very low in the East. Try to spot it.

In the beginning of August, Mercury is visible in the West just after Sunset. This image will quickly (after a few evenings) disappear as Mercury continues its path around the Sun. It revolves to a position behind the Sun, making it impossible for us to see. Saturn is 'behind the Sun' all month too, and we can not see it either.

The Moon comes close to Mars just before dawn on the 7th. The Perseid Meteor Shower peaks on the 12th, which is (coincidently) the date of the monthly New Moon. Let's hope for no clouds on this dark night. On the 21st, the Moon slowly (but fast in a telescope) passes Jupiter. On the 28th at about 6 AM, the Moon will slowly pass into the dark part of the Earth's shadow. Totality (when the Moon is entirely engulfed by the Earth's shadow) occurs between 6:52 AM and 8:23 AM. We will not be able to see the totality because the Sun will be rising before totality even starts. Go to Mexico or Western Canada to see it. The entire eclipse will be visible in California or Alaska. Take lots of pictures so you can share this experience with your friends. We'll see the beginning of the eclipse at about 4:20 AM. Happy viewing.