Mars rover transmits landing video

Nasa's Curiosity rover has transmitted a low-resolution video showing the last 150 seconds of its dive through the Mars atmosphere, giving Earthlings a sneak peek of a spacecraft landing on another world.

As thumbnails of the video flashed on a big screen, scientists and engineers at the Nasa Jet Propulsion Laboratory in Pasadena, California, let out "oohs" and "aahs".

The recording began with the protective heat shield falling away and ended with dust being kicked up as the rover was lowered by cables inside an ancient crater.

It was a sneak preview since it will take some time before full-resolution frames are beamed back depending on other priorities.

The full video "will just be exquisite", said Michael Malin, the chief scientist of the instrument.

Nasa celebrated the precision landing of a rover on Mars and marvelled over the mission's flurry of photographs - grainy black-and-white images of Martian gravel, a mountain at sunset and, most exciting of all, the spacecraft's white-knuckle plunge through the red planet's atmosphere.

Curiosity, a roving laboratory the size of a compact car, landed right on target late on Sunday night after an eight-month, 352 million-mile journey.

It parked its six wheels about four miles from its ultimate science destination - Mount Sharp rising from the floor of Gale Crater near the equator.

Extraordinary efforts were needed for the landing because the rover weighs one ton, and the thin Martian atmosphere offers little friction to slow a spacecraft down. Curiosity had to go from 13,000mph to zero in seven minutes, unfurling a parachute, then firing rockets to brake. In a Hollywood-style finish, cables delicately lowered it to the ground at 2mph.

At the end of what Nasa called "seven minutes of terror", the vehicle settled into place almost perfectly flat in the crater it was aiming for.

"We have ended one phase of the mission much to our enjoyment," mission manager Mike Watkins said. "But another part has just begun."

The nuclear-powered Curiosity will dig into the Martian surface to analyse what is there and hunt for some of the molecular building blocks of life, including carbon.

It won't start moving for a couple of weeks, because all the systems on the 2.5 billion dollar rover have to be checked out. Colour photos and panoramas will start coming in the next few days.

But first Nasa had to use tiny cameras designed to spot hazards in front of Curiosity's wheels. So early images of gravel and shadows abounded. The pictures were fuzzy, but scientists were delighted.

The photos show "a new Mars we have never seen before", Mr Watkins said. "So every one of those pictures is the most beautiful picture I have ever seen."

In one of the photos from the close-to-the-ground hazard cameras, if you squinted and looked the right way, you could see "a silhouette of Mount Sharp in the setting sun", said an excited John Grotzinger, chief mission scientist from the California Institute of Technology.

A high-resolution camera on the orbiting seven-year-old Mars Reconnaissance Orbiter, flying 211 miles directly above the plummeting Curiosity, snapped a photo of the rover dangling from its parachute about a minute from touchdown. The parachute's design can be made out in the photo.

"It's just mind-boggling to me," said Miguel San Martin, chief engineer for the landing team.

Curiosity is the heaviest piece of machinery Nasa has landed on Mars, and the success gave the space agency confidence that it can unload equipment that astronauts may need in a future manned trip to the red planet.

The landing technique was hatched in 1999 in the wake of devastating back-to-back Mars spacecraft losses. Back then, engineers had no clue how to land super-heavy spacecraft. They brainstormed different possibilities, consulting Apollo-era engineers and pilots of heavy-lift helicopters.

"I think it's engineering at its finest. What engineers do is they make the impossible possible," said former Nasa chief technologist Bobby Braun. "This thing is elegant. People say it looks crazy. Each system was designed for a very specific function."

Because of budget constraints, Nasa cancelled its joint US-European missions to Mars, scheduled for 2016 and 2018.

But if Curiosity finds something interesting, it could spur the public and Congress to provide more money for more Martian exploration.