American Craft Lands on Asteroid, Still Working

COLUMBIA, Md. (AP) - A strong radio signal, interrupted only briefly during the bounce, proved that the craft that was never designed to land had, in fact, come to a featherlight touchdown on Eros, more than 196 million miles from Earth, astounding even the officials overseeing the mission.

And it was still working.

It was the first time an American craft had made an initial unmanned landing on an outer space body, officials said. Unmanned Soviet craft arrived first on the moon, Venus and Mars.

``I am happy to report that the NEAR has touched down,' mission director Robert Farquhar said in announcing the Monday landing a few minutes after 3 p.m. EST. ``We are still getting signals. It is still transmitting from the surface.'

The 1,100-pound NEAR - Near Earth Asteroid Rendezvous - beat long odds to make its spectacular landing. Engineers had said there was less than a 1 percent chance of it surviving the impact and some NASA officials had forecast a ``controlled crash,' not a soft landing.

``We thought it would be all be over when it hit,' said Farquhar. ``This was a landing, not an impact.'

NASA administrator Dan Goldin said the achievement opens the way for later missions to asteroids and comets. He also admitted he never thought the NEAR landing effort would work.

``They pushed the boundaries,' said Goldin. ``Wonderful, bold, courageous, brilliant - those are the words that come to mind.'

``They made a spacecraft that was only designed to orbit and then they put it down on an asteroid and it's still working,' said Ed Weiler, NASA's chief scientist. ``That is amazing.'

Weiler said the NEAR landing taught valuable lessons that will help in future exploration of asteroids and comets. Such missions, he said, could be important if an asteroid such as Eros ever threatens the Earth. A similar space mountain is thought to have killed the dinosaurs 65 million years ago.

``This landing gives us a lot of practice,' said Weiler. ``We'll eventually want to land on comets.'

NEAR achieved orbit of Eros, an asteroid named for the Greek god of love, on Valentine's Day last year. It's mission will officially end on Valentine's Day this year.

Operating on instructions loaded in its computer, the craft fired braking rockets Monday morning to drop it out of Eros' orbit and send it spiraling downward. Four more rockets firings slowed it further, with the final burst coming even as it touched the surface.

The last rocket thrust, along with Eros' minuscule gravity, allowed NEAR to bounce, perhaps as high as 100 meters, said some engineers, and then to settle on the surface.

Farquhar said the landing speed was about 3.5 miles an hour, equal to a fast walk and almost exactly the speed engineers had targeted.

``We landed it pretty soft,' he said with a grin.

NEAR apparently came to rest with its solar power panels pointed at the sun, and an antenna pointing at Earth. Scientists said the craft transmitted a strong carrier wave, a sort of beacon that confirms its contact with Earth.

With solar power, the craft could send signals for about three months, but the Earth may never know. Farquhar said the mission officially ends on Wednesday and there are no plans to continue listening for NEAR's lonely call.

During its descent, NEAR furiously took pictures, each one showing the asteroid looming closer and closer. The final pictures captured surface features as small as a half inch.

``The clarity of those pictures is breathtaking,' said Goldin.

Engineers watching from Mission Control monitors broke into applause at confirmation of history's first landing of a manmade object on an asteroid. The mission, controlled by the Johns Hopkins University Applied Physics Laboratory, also was the first into deep space operated by a non-NASA center.

The landing completes a five-year, 2-billion-mile mission for the robot craft and boosts the cheaper-faster-better philosophy pushed by NASA for exploring outer space.

NEAR, developed by scientists at Hopkins, was designed, built and launched in just 26 months, far shorter than most NASA missions. It's cost, $223 million, was less than expected. Hopkins returned about $3 million to NASA, Weiler said.

NEAR traveled more than 2 billion miles during its five-year mission. It was launched Feb. 17, 1996, into an independent solar orbit. NEAR swung by the Earth once to pick up speed and then streaked outward toward Eros, an asteroid in an elongated orbit that nears Mars and approaches Earth's orbit.

In December 1998, a rocket firing designed to put the craft into Eros' orbit failed and NEAR sped past the asteroid. A second rocket firing series was successful and the spacecraft eventually returned to Eros and slipped into history's first orbit of an asteroid.

The NEAR spent a year snapping photos of Eros, second-largest of the asteroids that approach the Earth's orbit, and gathering readings of the asteroid's composition, structure and chemistry.

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