Rendezvous with the Red Planet

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Courtesy of Griffith Observatory

Mars in all its fiery glory will be closer to Earth in the early hours of Aug. 27 than since the time of the Neanderthals, about 60,000 years ago.

At a relatively close distance, Mars will be 34.6 million miles from Earth (its maximum distance is 248.5 million miles). According to Sky & Telescope magazine, this is one of the five chances, at most, in your lifetime when you can see Mars so clearly, with spectators in North and South America and several Pacific Islands having the best views.

“It’s the brightest thing in the night sky,” said astronomer John Mosley, program director for Griffith Observatory. “It totally outshines the other stars in the sky, including Antares,” which is usually the brightest star in the southwestern sky and is located to the right of Mars.

“Those with access to a telescope, it’s a great chance to see the romantic markings on Mars” such as the south polar cap, Mosley said. “Mars is tilted so that we

are looking on the Southern Hemisphere. It’s late spring on Mars. If you have a good telescope you can see the clouds forming over the North Pole.”

Even observers with binoculars and modest telescopes can get a good view of the planet, unless a seasonal dust storm, a phenomenon caused by solar heat when Mars gets close to the sun (as it is now), obscures the planet’s surface. These ochre-hued dust clouds can be as small as a dust devil that swirls for a few days, or as large as an atmospheric blanket that covers the planet, the effects of which can last for months. Fortunately, for astronomers, these storms are considered rare.

The close proximity between Mars and Earth is due to the elliptical orbits of both planets and the speeds at which they orbit the sun. Earth is at its farthest point from the sun, Mars at its closest. The two planets will rendezvous together about half a dozen times between now and the year 3000, with the closest in 2779, at a distance of 34.58 million miles.

In some ways, Mars resembles our planet. The length of a day on Mars is nearly identical to the 24-hour day on Earth, but its calendar year is 687 Earth days. Similar to Earth, the terrain of Mars is made up of canyons, mountains, deserts and polar ice caps.

Above the Red Planet there are two moons-Phobos and Deimos. The red color suggests hot temperatures, but Mars is actually quite cold, with an average temperature of -81 degrees Fahrenheit, although temperatures can reach 50 degrees Fahrenheit at the equator. And its gravity is much less-you would weigh less than half your weight on Mars. Although this may seem desirable to many dieters, another reason we couldn’t survive on Mars is that its atmosphere is nearly oxygen-free, consisting of 95 percent carbon dioxide.

Speculation about life on Mars has been bandied about for many years, perhaps beginning with Percival Lowell of Arizona, who built a telescope in 1894 and observed what appeared to be long lines crisscrossing the planet that resembled canals. These “canals” turned out to be an optical illusion, but theories about life on the Red Planet refused to go away. The fear that Martians had landed in New Jersey was on the minds of many listeners who heard Orson Welles’ realistic but fictionalized radio broadcast, “War of the Worlds” in 1938.

We came closer to answering the life on Mars question when a rock that fell to Earth from the planet was analyzed by NASA, leading scientists in 1996 to announce there might indeed be life there. Mars will be scrutinized within the next few months more than at any other time in history due to three missions in December and January.

NASA has launched two spacecraft rovers-Spirit and Opportunity-which will land on Mars in January. The rovers with their field geology robots will photograph and analyze surface rocks to shed light on, among other things, the intriguing theory that life began on Earth via a meteorite that fell from Mars, where life originated as one-celled entities.

Great Britain has launched Mars Express and its piggyback lander, Beagle 2, which will search for signs of past life by gathering information about the terrain and atmosphere. The lander will arrive on the planet in December. And a probe from Japan, called Nozomi, is expected to reach Mars in January.

Has there ever been life on the Red Planet? Perhaps we will soon find out.

To celebrate the planet’s arrival, Griffith Observatory will host a free late-night Mars party on Aug. 26 from 10 p.m. to 1 a.m. on the south lawn of the Autry Museum of Western Heritage, 4700 Western Heritage Way. Telescopes will be available to participants.

For more information about Mars, call the Sky Report at 323.663.8171.