Star Points for October, 2005; by Curtis Roelle Planet Mars, Arriving on Track Four! Mars, the fourth planet from the sun and next farthest out from ours, is making a comeback this Fall. It hasn't been closer since the Summer of 2003. Back then Mars was really close. How close? According to astronomer Guy Ottewell the two planets were the closest they had been since 57,537 BC! Although they won't be as close this time there is an advantage. Mars culminates, or is best placed for viewing during the night, higher in the sky this year than in 2003. This means that there will be less atmospheric distortion since we peer through less atmosphere when looking at higher objects than lower ones. Such close encounters occur at "opposition" when Mars' position in our sky is directly opposite from the sun. Thus, when at its closest, on the night of October 29-30, Mars rises as the sun sets, reaches its highest point in the sky around local midnight, and sets when the sun rises. Mars is smaller than Earth. Let's model them. If we let a silver or Eisenhower dollar coin represent the diameter of the Earth, then Mars would be the size of a Jefferson nickel. When closest Mars will be 43 million miles from us. At that distance its angular size will be 20.2 arc-seconds. What does that mean? It means that Mars will appear to be as big as a nickel 355 feet away. Say that you're standing on a regulation football field with 10 yard deep end zones. Ask someone standing on the outer edge of one end zone to hold up a nickel. Walk to the opposite end zone's outside edge, turn around, and take two steps back toward the nickel. Now look at the nickel being held in the opposing end zone. That is how large Mars will look from earth. Likewise, hold up your dollar so that the person holding the nickel can see how big Earth looks from Mars. How much detail can you see on the nickel? Can you tell whether you are seeing heads or tails? Does a pair of binoculars help? How about a small telescope? Experiment and find out. Speaking of telescopes, what can you see on Mars using one? The prominent telescopic features include the southern polar cap and the dark mare regions. The most prominent feature in my opinion is the dark mare named Syrtis Major. It's a region whose shape reminds me of India. Mars is easily visible to the naked eye appearing as a bright yellowish-orange "star" in the constellation Aquarius. In early October Mars rises around 9 p.m. EDT and is at its highest at around 4 a.m. At month's end with the blessed end of daylight time Mars is highest a little after midnight. Weather permitting the Westminster Astronomical Society will have telescopes set up at Bear Branch Nature Center from 8-11 p.m. on Friday, October 7. Mars will just be getting well placed about quitting time. That night there will also be shows in the nature center's planetarium at 07:30 and 08:30 p.m. Call the nature center for pricing and reservation information at 410-848-2517.