At 10:31 p.m. PDT on Aug. 5, after scarcely 9 months of travel, NASA‘s Mars Science Laboratory goal (with a corsair named Curiosity) will arrive during a Red Planet.
The $2.5 billion corsair will start a two-year query to try a interior of Mars’ Gale Crater and hunt for justification of an ancient sea there. But before this hunt can begin, Curiosity has to land.
The Mars Science Laboratory landing process has been a subject of many contention even before a goal launched on Nov. 26, 2011. Nicknamed “seven mins of terror,” a spacecraft’s entry, skirmish and alighting process will need a lot of things to go ideally right — all before anyone on Earth receives even a singular signal, due to a length of time it takes for information to transport from Mars to Earth.
“By a time we get a initial vigilance that says ‘okay, I’ve now reached a tip of a atmosphere,’ in existence a corsair has already been on a aspect for 7 minutes,” pronounced Steven Sell, emissary operations led for Entry, Descent and Landing during NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “It’s like your child personification in a vast game, and we can usually lay there in a stands and watch. It’s a nail-biter all a way.”
When the Curiosity corsair arrives during Mars it will be roving during a quickness of 13,000 miles per hour (21,000 kph). Within 7 minutes, a car needs to get down to a quickness of 0 miles per hour — all in one piece, of course, and in a right spot. [Mars Rover's Sky Crane Landing (Infographic)]
The initial step in this routine will be a guided entry, during that a whole MSL booster (currently consisting of a corsair and descent stage tucked into a protecting aeroshell) will adjust a march toward a 12-by-5-mile-diameter alighting ellipse — usually an eighth a distance of a alighting targets of prior rovers.
As it impacts Mars’ atmosphere during some-more than 13,000 mph, MSL’s feverishness defense will take a brunt of a frictional heating generated by a deceleration, and will shortly feverishness white-hot with temperatures reaching 1,600 degrees Fahrenheit (870 degrees Celsius). Even by this, MSL will still be physically running itself toward Gale Crater, banishment rockets to keep it on track.
The atmosphere on Mars, 100 times thinner than Earth’s, isn’t unenlightened adequate to delayed MSL down by itself. So during this indicate a parachute will be deployed — literally a largest supersonic drogue trench ever combined — to delayed MSL down from 1,000 mph (1,600 kph) to about 200 mph (320 kph), subjecting a booster to 9 Gs of force. (That’s 9 times a lift of Earth’s gravity.)
Then, with a aspect of Mars still coming rapidly, a spacecraft’s feverishness defense will be jettisoned, exposing a tangible corsair and permitting it to use a radar running complement to establish only how high it is. This is one of a many essential tools of a descent, given it’s not until afterwards that MSL will be means to check a altitude.
“When a feverishness defense comes off and a radar turns on, we need to find a ground,” pronounced Sell. “When we initial eject a feverishness defense we’re too high for a radar to see a belligerent yet, so we have to wait a unequivocally prolonged 20 to 30 seconds, adult to a minute, until a radar can get tighten adequate to a belligerent to be means to see it. Without that resolution it doesn’t even try to do a rest of a landing.”
And once that’s all done, it’ll unequivocally start to get interesting.
Making a hold down
At scarcely 2,000 pounds (900 kg), Curiosity is simply too vast to land with airbags like prior rovers. Instead, engineers devised a process that’s never been attempted before: a sky crane.
When MSL reaches precisely a right altitude, a skirmish stage, retaining a Curiosity corsair within a sky derrick structure, will dump from a aeroshell and fast glow a thrusters, relocating it safely divided from a descending behind bombard and negligence it further.
Curiosity will be carried usually downwards by a skirmish stage, that will use a Mars Descent Imager (MARDI) camera to scheme over a aim and, once during a tallness of 20 meters (about 65 feet) use rockets to float in place while it lowers a corsair down to a aspect on bridles and an umbilical cord — all 3 of that are temperament a weight of a rover.
Although a complement has been exhaustively tested on Earth regulating simulations and unequivocally modernized mechanism models, a initial time it’s going to play out in full will be during a tangible alighting on Mars.
“It’s a ultimate margin test,” Sell said.
As shortly as Curiosity has overwhelmed down, a cords will be cut and a skirmish theatre will soar safely off to a side, crashing onto a Martian aspect distant adequate divided to poise no risk to a rover. At this indicate Curiosity, wheels down, is prepared to start a mission.
That is, as prolonged as all goes accurately and precisely as planned. On a night of Aug. 5, a whole universe — not to discuss utterly a few folks during JPL — will be examination to see how a corsair a distance of a Mini Cooper can be sent hundreds of millions of miles to hold down on a aspect of another planet.
“We’ve been scheming for this for many, many years … we’re vehement to get out there and land this thing,” Sell said.
- Mars Rover Curiosity: Mars Science Lab Coverage
- Mars Rover Landing: NASA Set for Curiosity’s Red Planet Arrival (Photos)
- The Boldest Mars Missions in History
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