Earth to Mars: Come closer
Jupiter may be king of the mythological gods. But, among the planets, it's Mars' time to shine. When it draws closer to Earth than it has in some 60,000 years next Wednesday, it will be brighter than any planet except Venus. And, since Venus makes only a fleeting appearance at sundown, it won't steal the Red Planet's show.
At 5.52 a.m. eastern daylight time Aug. 27, Mars will be a "mere" 34,848,754 miles (55,758,006 kilometers) away. That's 1,188 miles (1,900 km) closer to Earth than Mars came in 1924.
As the Observer's Handbook of the Royal Astronomical Society of Canada points out, the opportunity to study Mars from Earth will be "as good
as it gets" over the next few weeks. The planet will reach its maximum possible angular diameter on the sky of 25.1"
Located 25 degrees south of the celestial equator, it will rise high enough above the horizon for easy viewing in many locations - 30 degrees for an observer at 45 degrees north latitude and higher up farther to the south. Mars will not come closer until Aug. 28, 2287. So grab the children on a clear evening for a rare opportunity to see Mars at its best.
You don't need a telescope to enjoy the show. Just watching the progress of the brilliant red disk through the stars in coming weeks can be fascinating. Mars has been moving backward relative to the stars. It will halt this westward motion Sept. 29 and begin to move eastward like the Moon, stars, and other planets as the relative motion of Earth and Mars changes.
The view through even a modest telescope or binoculars should be stunning. Mars is presenting much of its southern hemisphere. It's summer there, so there won't be much of a southern polar cap.
However, many prominent markings should be easily seen. You'll be looking at desert. Even the darker features - once mistakenly thought to be vegetation - are dry.
There is a caveat. Martian haze and thin ice clouds - to say nothing of a dust storm - can dim the view. So far, there's no sign of the kind of dust pall that ruined viewing during Mars' 2001 close approach.
There's help for observers with Internet access. Space.com has posted a complete viewer's guide on its website: www.SPACE.com/spacewatch/where_is_mars.html. NASA promises to make Hubble Space Telescope images available through its nasa.gov website beginning shortly after Aug. 27.
NASA expects the Hubble images to be "the sharpest views of Mars ever taken from Earth," showing details as small as 17 miles (24 km) across. Such detail can help you identify what you see with your own small telescope or binoculars.
And yes, there are other things to see in the sky - the usual stellar objects and some of the other planets. Jupiter, now dimmer than it has been, will become a morning object next month. Venus is beginning to emerge again as the "evening star." Yet this time really belongs to Mars. Look for it rising late in the evening.
• Skywatch is an occasional column.