I'm not trying to recreate H.G. Wells' War of the Worlds, but our night sky is under invasion from Mars. For virtually the rest of the month, our neighboring red planet will be dazzling all night long as it rises in the east at sunset and sets in the west at sunrise. It's also the brightest and closest it's been to Earth in more than two years. Mars has just passed an astronomical alignment called opposition that occurs when our Earth lies in a line between our sun and Mars. Because Mars is more distant to the sun than we are, and the fact that it takes Mars takes nearly twice as long to circle our home star, it takes nearly 780 days for Earth and Mars to reach their most immanent rendezvous. We can't exactly reach out and touch Mars because it's still 63 million miles away, but it's close enough to get your attention.
The time between Mars-Earth oppositions is called the synodic period, but not all Mars oppositions are created equal. Some opposition distances are closer than others. That's because Mars's orbit around the sun is slightly more lopsided than Earth's orbit. Unfortunately, this time around, the opposition distance between the two planets is not all that close. Back on Aug. 27, 2003, Mars and Earth were separated by less than 35 million miles. It hadn't been that close to Earth in 60,000 years.
Even though Mars is at one of its more distant oppositions this time around, it's still the fourth brightest star-like object as evening begins. Only the two bright planets Jupiter and Venus that are in a super close celestial hug in the western sky and the bright star Sirius are brighter than Mars.
By the way, I have a lot more to say about the sensational conjunction between Venus and Mars in next week's Starwatch column.
Even if you're watching Mars from the inner city in the evening, you can't miss it. It starts out after evening twilight low in the eastern sky and with even the naked eye, it'll sport a fiery red hue.
If you're a little farther out in the countyside, you'll see a formation of stars that resembles a backward question mark leaning the left. That outlines the chest and head of the constellation Leo the Lion. The star that makes the "period" of the question mark is Regulus that marks the heart of the celestial lion. It's the next brightest luminary closest to Mars.
To be totally honest, Mars will not be an awe-inspiring object, through most telescopes, but it's still worth your time. The problem is twofold. First, Mars is not all that close this opposition at 63 million miles, coupled with fact that it's only 4,000 miles in diameter. Realistically, about all you'll see is a small reddish disk through even moderate to large telescopes, but if conditions are just right, you might see dark markings on the planet that are part of its extensive system of valleys. The marking do change their positions from night to night and even hour to hour. That's because Mars rotates of its axis every 24.6 hours, a little slower than our Earth.
You may see that part of the lower edge of Mars's disk has a whitish hue to it. That's Mars's northern polar cap. It'll appear on the lower half of Mars, assuming that your telescopes, like most, give you an upside-down reverse image. Otherwise, if you get a direct view, the polar cap will be on the upper edge of the disk.
There's a great website from Sky and Telescopes Magazine that does a really nice job showing you the side of Mars that's facing Earth at any given time. Just browse Sky and Telescope Mars Profiler or go to http://www.skyandtelescope.com/observing/objects/planets/3307831.html# and set the date and time.
It's also a good idea to wait until Mars is higher in the sky to view with your telescope so you don't have to look through so much of Earth's blurring atmosphere. After about 10 p.m., Mars should be high enough in the heavens for you to get a clearer view of our ruddy neighbor.
Also, remember to take long continuous looks through your telescope to let your eye get used to the light level and to catch the times when Earth's atmosphere is a little more transparent. Upper winds are constantly changing how clearly we can see celestial targets, even if there aren't any clouds. After 10 p.m., be sure you don't confuse Mars with the bright red star Arcturus. It'll look just like Mars, but will be about 40 degrees - or about four of fist widths held at arm's length - to the lower left of Mars.
It's also a good idea to let your telescope and all the eyepieces you'll be using to sit outside for an hour before you aim it Mars so the optics can acclimate to the outside temperatures.
Thanks to all of the orbiters and rovers flying and crawling over Mars in the last 40 years, we know a whole lot more about Mars. I think the key discovery is strong evidence of liquid water underground. Where there's water, there's the possibility of life. Because of Mars's low atmospheric pressure, liquid water can't exist on the surface. One thing for sure: Mars definitely had a more watery past both on the surface and in its atmosphere.
Stay tuned; new discoveries are constantly being made.
(Lynch is an amateur astronomer and author of the book, "Pennsylvania Starwatch.")