CSS Space News - 10/20/94

by Ross Brown

Cable Blackout

Were any of you watching TV last Monday? Were you watching a cable channel? Did it mysteriously go haywire? The cable company could do nothing about either.

What happened!?! Well, since we are nearing the winter months, and since the Earth's axis is inclined by 23 degrees off the vertical plane of the solar system, we here in North America are moving farther and farther away from the apparent celestial equator. Elementary stuff, I know, but it affects more than the weather.

The communications satellites' orbits take them directly between the Earth-bound recieving stations and the Sun at this time of the year. When your cable company's dish antanna looks up at the sky expecting to hear "I Love Lucy" reruns, it gets a megado se of microwave (and other wavelengths as well) radiation from the sun. While the communications satellites' power cells can only pump out a few watts of transmitting power, the sun can pour out thousands of watts of raw energy. Naturally the sun is goi ng to win at these times.

Also, about 12 hours later, the satellite will find itself in the shadow of the Earth. Since it runs on solar power most of the time, the satellite has to switch over to batteries. Hopefully the relays and batteries are still working after years of fai thful service in orbit...

Be on the lookout for this phenomenon next spring, when the same thing happens over again.

Landing Site Chosen for Mars Pathfinder Mission

The Mars Pathfinder, set to land on Mars in 1997, will touch down on an ancient flood plain. This flat land is the site of what look like great floods of water. These features are rather mysterious as there is little or no water on Mars today. From sp ace, these flatlands look like riverbeds or places where water has rushed through.

The landing site itself is 850 km southeast of the Viking 1 landing site (1976). It is in an area known as Ares Vallis. The site was chosen because it should shed some light on the mystery of the ancient floods, and because it should have a variety of rocks and soil to analyze.

The Pathfinder craft will contain two parts, a stationary weather station and a tiny microrover to crawl over the surface in search of interesting stuff to look at. It will use a parachute to descend to the surface, where airbags (like your car) will in flate and cushion the fall. After bouncing across the surface like an inflated ball, the craft will open like a flower and the rover will roll out. Cute 'huh?

Of Contacts and Astronauts

So you are an astronaut and can't see to well, what are you going to do about it? Glasses are a no-go on the shuttle or even the space station, if it gets launched. Can you wear contact lenses in space?

Only if you are a payload specialist or a visitor (read: influential congresscritter), and then only hard contact lenses are allowed. The problem with soft contacts are that they dry out a lot quicker in micro-gravity because of their delicate fluid balance.

The bright side is that gravity induced eye problems like astigmatism could possibly be helped by prolonged missions in space. Who knows?

---