LOOKING FOR NEW TELESCOPE TO VIEW SKY

I do not really care if March comes in like a lion and leaves like a lamb just as long as it gives me a "few" clear nights. A "few" clear nights pretty well sums up the winter weather so far this year. Every now and then I turn on my computer planetarium software and set the time advance for minutes and let it run. Just seeing the fake stars rise and set is sort of like looking at your old baby pictures. You cannot decide if you actually remember the event or you have fake memories because you looked at them so much.

March represents the last good chance to view the planets Venus, Jupiter, and Saturn. Venus turns into a giant thin crescent shape and then completely disappears at the end of the month while Jupiter and Saturn are just days away from the distorting atmosphere near the horizon. The first quarter moon is close to Saturn on the 28th and close to Jupiter on the 29th at sunset. Also at sunset the constellation Orion is high in the south just ahead of the meridian at the first of the month and just past the meridian at month's end, while the Big Dipper is high overhead around midnight.

I get quite a few questions regarding the global warming issue given its popularity in the "Speak Out" column. So here are my observations regarding the scientific evidence. The Earth is about 40 degrees warmer with our current atmosphere than it would be without one. This is because greenhouse gasses like carbon dioxide and water vapor hold the heat in. Carbon dioxide only makes up about 3 percent of the atmosphere but is responsible for at least half of the greenhouse effect. Since it is such a small amount but has a strong effect, man may have the ability to alter its concentration with unknown consequences. Even if you increase the amount of carbon dioxide (which we have) it is not clear if we get more trees, more coral in the oceans, more rain, higher temperatures, or all the above.

Geologists drilling into the polar ice caps can determine the temperature of the Earth over the last several hundred thousand years.

They see rhythmic heating and cooling of the overall Earth by 10 to 15 degrees over a few thousand years. The change that scientists are arguing about now are a few tenths of a degree. It is hard for me to understand the significance of a few tenths of a degree when we know that in the past and in the future there will be temperature changes 100 times bigger. Despite our temperature history, it just makes sense to not abuse the Earth any more than we have to.

At a recent national astronomy meeting the excitement was running high as astronomers have now discovered more than 50 planets orbiting around nearby stars. All of these have been massive, Jupiter-like planets, but NASA's director, Dr. Daniel Goldin, delivered a passionate speech asking the community to find Earth-like planets within five years and to actually image these planets in 10 to 15 years. NASA has envisioned arrays of eight meter-sized telescopes in space forming images of distant planets with enough detail to detect oceans, clouds, and land masses. Studies are already underway to determine the best filters to view the planets with. Judging by the response of the audience I would say the community enthusiastically embraced the challenge.

If the public and Congress agree that this is something we should do, we could be in for an Apollo Moon landing type program. NASA will have to develop large, plastic, thin mirrors for these large telescopes which means you and I may have a 3-foot diameter telescope in our backyard someday. Of course, you will need a "few" clear nights to make it worthwhile.

Mike Cobb is a professor in the physics department at Southeast Missouri State University and can be reached at 651-2172.