RAY SUAREZ: These are the last images that the "NEAR" spacecraft sent back before its near perfect landing Monday on the asteroid Eros. The craft is still transmitting radio signals to Earth as it hitches a ride on this rock hurtling through space. "NEAR" stands for Near Earth Asteroid Rendezvous, it was launched five years ago. The original mission was to orbit Eros and collect information about its composition. "NEAR" did that, and much more. Scientists say it will take decades to analyze the 160,000 photos and reams of data that "NEAR" gathered. An asteroid is too small to be a planet, but also orbits the Sun. They are like comets, but with no glowing tail of gas. Most are much smaller than the 21-mile long Eros. Robert Farquhar is the NEAR mission director.
ROBERT FARQUHAR: To get an idea of the size of it, you can see that this is Manhattan Island under here, and you see that this asteroid is about, well we say it's twice the size of this, well it doesn't look like it, maybe it's one-and-a-half times the size of Manhattan Island.
RAY SUAREZ: It took "near" four years to reach Eros. Last year, on Valentine's Day, the 1,100 pound spacecraft began orbiting the potato-shaped asteroid named for the Greek God of Love. This week, the spacecraft's mission was complete. Its fuel, and its time, were running out. Scientists decided to attempt a controlled descent. It's a risky maneuver for a craft not designed to land on anything; for a craft with no landing gear of any kind. One engineer compared it to flying between the blades of a spinning propeller, Eros is in constant rotation and has no gravity of its own. "NEAR" fired its rockets five times, enabling it to drop from its 15-mile high orbit. It hit at a speed of less than four miles per hour and bounced off the rocky, barren surface before landing again.
ROBERT FARQUHAR: I'm happy to report that the "NEAR" spacecraft has touched down on the surface of Eros. This is the first time that any spacecraft has landed on a small body. (Applause)
RAY SUAREZ: These pictures, from 200 million miles away, light up a hidden world for scientists. Eros has thousands of large craters on its surface, indicating impacts with other objects. The asteroid is littered with more than one million huge boulders, some as large as Houses.
ANDREW CHENG: Oh, we have learned much more than we ever set out to. This mission has been a fantastic success -- and it has met all of its science objectives and we have been surprised and delighted with the results that have come back.
RAY SUAREZ: At a press conference, astronomers provided insights about what they learned.
JOSEPH VEVERKA: What's intriguing about the surface is that the surface at the resolution we see is covered by boulders, and apparently in many places by much finer debris. And one of the issues is: Where does this stuff come from? We also know, amazingly, as you saw, there are no small craters. One hypothesis, which I personally think is unlikely, is it's not being hit by anything to produce small craters, okay, I don't believe that, okay? So that, to me, says there is something very efficient if you're a very small crater, you don't last long enough to be caught by a glimpse such as we've obtained. Having answered a few questions these images have presented us with a bag full of mysteries that will keep us scratching our heads for years to come.
RAY SUAREZ: Since "NEAR" gets its power from the sun, it may continue to send signals back to earth for several months; the mission has been extended for ten more days to get some of that data, but after that, no one on Earth will be listening.