building the next global dust storm? 'They're fun to watch,' says Parker. And if 'seeing is good' you might catch a glimpse of some dust clouds. Right: John Nemy and Carol Legate took this recent picture of bright Mars and a meteor above their campsite on Blackcomb Mountain, Whistler, British Columbia.Įven a small telescope will reveal the planet's orange disk and its icy south polar cap. (If you live in the southern hemisphere, look northeast instead.) Mars will be there in the southern sky, a remarkably bright red star. Step outside before dawn anytime this month. Already in July Mars is a pleasing sight. It was a complete success.Īs 2003 unfolds, Earth and Mars are drawing together for their closest approach in some 60,000 years on August 27th. Then they carried on with Mariner 9's mission: to photograph the entire surface of the planet. Mission controllers simply waited a few weeks for the storm to subside. The planet was completely obscured not even the polar caps were visible. Viking data will give them a head start.įive years earlier, in 1971, the Mariner 9 spacecraft reached Mars during the biggest dust storm ever recorded. As far as researchers were concerned, it was a good opportunity to study such storms from the inside-something Mars colonists may do again one day for themselves. The Viking landers of 1976, for instance, weathered two big dust storms without being damaged. NASA spacecraft have encountered Mars dust before. Will dust storms cause problems for those missions? They include three landers and two orbiters. Northern-hemisphere sky watchers should look south southern-hemisphere sky watchers should look northeast to find the bright red planet.Ī total of four spacecraft from NASA, the European Space Agency and Japan are en route to Mars now. 'This means the season for dust storms is just beginning,' says Bell.Ībove: Mars lies in the constellation Aquarius, which is best seen this month during the hours before local sunrise. During the weeks around perihelion, sunlight striking Mars will be 20% more intense than the annual average. Mars reaches perihelion-its closest approach to the sun-on August 30th. The planet goes around the sun in a 9%-elliptical orbit with one end 40 million km closer to the sun than the other. Sunlight on Mars is about to become unusually intense. (For comparison, the reflectivity of typical martian terrain is 10% to 15%.) These fine grains reflect 20% to 25% of the sunlight that hits them that's why the clouds look bright. 'Airborne dust on Mars is about as fine as cigarette smoke,' says Bell.

Solar heating warms the martian atmosphere and causes the air to move, lifting dust off the ground.īecause the martian atmosphere is thin-about 1% as dense as Earth's at sea level-only the smallest dust grains hang in the air. Īll dust storms on Mars, no matter what size, are powered by sunshine. Left: An orange billiard ball: a world-wide dust storm on Mars in 2001 blurred the planet's normally sharp features. 'Only 10 global or planet-encircling dust storms have been reported since 1877,' notes Parker. Rarely do they become a planet-wide event. They persist for a few days or weeks, then dissipate. Mars Global Surveyor and Mars Odyssey, two NASA spacecraft circling Mars, have seen many 'regional storms' like the cloud near Hellas Basin now.

Face of mars nasa