The Ares I and Ares V rockets both are required to get rockets into orbit. The Ares I can get 22 metric tons into low Earth orbit, compared to 25 metric tons for the Space Shuttle, in part to service the space station. The Ares V can get 53 metric tons to the moon by itself and 65 when paired with an Ares I.
(Credit: NASA) To lift more weight, there are two rockets, Ares I and V, instead of Apollo's one rocket. The smaller Ares I is designed to carry the crew--as many as six, four of whom can land on the moon. The more powerful Ares V is for carrying the Altair lunar lander and anything else destined for the surface of the moon, such as a pressurized vehicle or a lunar dwelling.
The two rockets' contents will be united in orbit around the Earth, then the cargo in the tip of the Ares V, called the Earth departure stage, will carry the crew and lander to the moon, according to the plan. As with Apollo, the lander will make the descent to the moon while some crew remain above in an orbiter.
The lander itself looks as awkward as the original Apollo landers, including the four splayed legs. But it's bigger, with enough resources to keep four people on the lunar surface for a full seven days, compared to two for Apollo.
On the way back, the bottom half of the lander stays put on the moon while the ascent stage docks with the orbiter in orbit about 100 kilometers above the lunar surface. The crew is reunited, the ascent stage is discarded, and the crew return to Earth, eventually plunging through the atmosphere in a conical capsule
For Mars, things get more complicated, though details are not pinned down yet. The lunar missions are designed to let engineers work out the issues. Even under the optimistic schedule, a Mars return is set tentatively for 2030.
Meanwhile, in 2009
NASA's present work is designed to lay the groundwork for a manned moon mission with two spacecraft that were launched June 18.
First is the Lunar Reconnaissance Orbiter (LRO), which has begun mapping the lunar surface from the very low elevation of 50 kilometers, or about 31 miles. NASA plans to release its first images of proposed landing sites on Friday.
But the rocket could carry a little more payload, so piggybacking on the trip is the second craft, the Lunar Crater Observation and Sensing Satellite (Lcross). This craft will come to a deliberate and dramatic end October 9, when first the Centaur rocket that carried it and the LRO to the moon smashes into a crater at a speed of 1.55 miles per second, then Lcross itself follows shortly after.
The LRO and Lcross spacecraft are the colorful objects at the tip of this rocket. LRO has begun mapping the moon in detail, and Lcross will watch as the 5,000kg trailing Centaur rocket system smashes into the moon. After studying the resulting debris, Lcross itself will collide.
(Credit: NASA) Various Earth-bound telescopes and the Hubble will watch the plume, too. And because the plume will be visible from Earth with modestly powerful telescopes, NASA hopes amateur astronomers will send in their own photographs to help analyze the position and visibility of the plume.
So why the south pole?
The Apollo missions landed on the moon's equatorial regions, a navigationally simpler task. But there are good reasons to visit the polar reasons when it comes to human habitation resulting from the fact that some rises are in permanent sunlight and some crater interiors are in permanent shade.
Scientists have found the physical signature of hydrogen in the polar regions, leading them to believe it's possible there is ice hidden in the shade. The ice, likely the leftovers of eons of comet impacts, is useful for human consumption and, more grandly, for producing rocket fuel by splitting it into the liquid oxygen and liquid hydrogen that are today's rocket propellant of choice. And, of course, oxygen is necessary for breathing.
"If we can find water, it greatly enhances our ability to set up a long-term outpost or permanent moon base," Hunt said. Scientifically, "it'll help to fill in gaps about the early evolution of the moon and the earth-moon system and solar system if we can say yes, indeed, there's water there."
Lunar high ground on the polar regions benefit from permanent sunlight, too. That makes for an easier, balmier climate and means rotating solar panels can track the sun at all times with ease, Connolly said.
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