After 50 years of missions to Mars, scientists are unlocking some of the mysteries surrounding a planet that has captivated mankind for millenniums. Will ?humans ever leave a boot print on Mars?
A self-portrait of NASA's Mars exploration rover, 'Spirit,' in 2006. This is the cover story in the Jan. 14 edition of The Christian Science MonitorWeekly.
Courtesy: NASA/JPL-Cal Tech/Cornell/Arizona State
EnlargeThe mood among mission controllers was subdued. Scientists at the National Aeronautics and Space Administration's Jet Propulsion Laboratory (JPL), in the foothills of southern California's San Gabriel Mountains, were worried about the landing of their spacecraft on Mars.
Skip to next paragraph' +
google_ads[0].line2 + '
' +
google_ads[0].line3 + '
Subscribe Today to the Monitor
With good reason.
Three months earlier, in September 1999, the Mars Climate Orbiter had arrived at the red planet, only to burn up in the atmosphere instead of taking up its intended orbit. Now, on Dec. 3, NASA officials were nervous about the fate of the Mars Polar Lander as it approached the planet, even though they had taken all the precautions they could to prevent a similar mishap.
"The tension was palpable," recalls Scott Hubbard, then a deputy director at NASA's Ames Research Center Laboratory, who was at the event. "Everyone was on edge."
Their anxiety turned out to be prophetic. When the $110 million lander finally touched down on the planet, it did so with all the subtlety of Wile E. Coyote's anvil falling off the cliff. Investigators later posited that the most likely cause was a bogus "I've landed" signal sent to the computerized flight-control system when, in fact, the lander was still 131 feet up. It had deployed its legs as planned. But that triggered an errant signal that caused the landing rockets to shut down prematurely, leaving the craft to crash into Mars at about 50 miles per hour. Controllers were never able to make contact with the lander or the two probes it ferried.
The debacle marked a low point in NASA's decades-old quest to explore Mars. The loss of the lander was the third failure in six years. In the 13 years since, however, the effort has undergone a remarkable turnaround. The agency has overseen the most comprehensive, systematic ? and successful ? effort to investigate another planet since the dawn of the Space Age. A string of six triumphant orbiters, landers, and rovers has helped unlock mysteries about a planet that has captivated humans since the Babylonians.
Now, as the most sophisticated rover humans have ever sent into the cosmos inches its way along the planet's ruddy surface, mankind may be reaching a hinge moment in the study of Mars. Curiosity's slow journey across Gale Crater marks a shift from tracing the history of water on Mars to focusing on efforts that could help answer a question humans have been asking since Dutch astronomer Christiaan Huygens drew up the first practical sketches of the planet in the mid-1600s: Did Mars ever host life?
Curiosity's landing alone was euphoric for NASA: Its soft touchdown in August, at the end of a "sky crane" tether, heralded a new era of precision landings that was watched by millions around the world, creating a triumphant moment for an often-beleaguered space agency.
Centimeter by centimeter, Curiosity is hunting for evidence that Gale, a desiccated ding in the planet's surface with a central peak towering 18,000 feet above the crater floor, may have harbored conditions that permitted primitive life to exist early in Mars' history. But that's just one spot on the planet ? akin to trying to figure out the biological history of Earth by landing solely in rural Chile (which scientists often use as a stand-in for Mars).
1?|?2?|?3?|?4?|?5Source: http://rss.csmonitor.com/~r/feeds/science/~3/LQaDnR0_MY4/The-Mars-mystique
album of the year grammy red carpet grammy award winners the band perry grammy awards whitney houston autopsy dobie gray
কোন মন্তব্য নেই:
একটি মন্তব্য পোস্ট করুন