Watch video of the Asteroid Eros in orbit , captured by the NEAR-Shoemaker spacecraft.
APL built NEAR and serves as mission control for the asteroid-surveying space probe.
"We're being cautious. We want to get a better handle on the gravity field as we fly in so low. The main purpose is to get higher-resolution pictures and gather other important data too," he said.
After NEAR completes its surface-skimming passes in October, the spacecraft would be placed into a 125 mile by 125 mile ( 200 kilometer by 200 kilometer) orbit around Eros.
How low can you go?
Meeting June 26 at APL, NEAR science team members also approved a plan to do as many close passes as possible above Eros between January 10 to February 14.
Those are NEAR's final weeks where the on-board fuel level and funding conspire to bring the space probe's mission to a finale.
"We're likely to run out of fuel part way through this scenario. So when the thing likely crashes, we don't want the public to think we had a failure. It won't be scattered all over the place. It's likely to be a highway accident. Toward the end, we'll be running on fumes," Farquhar said.
"Those flybys would be riskier. This is a proposal that still has to be cleared with NASA Headquarters," Farquhar said. A minimum altitude that NEAR would reach to swoop close to Eros is 1,640 feet (500 meters), he said.
Images snapped of Eros toward mission's end may reveal details on the
surface down to 10 centimeters or less. "That's pretty high resolution," Farquhar said. "We might have to come in as though we're going to land, but stop it short, maybe at a half-kilometer (0.3 mile) above Eros," he said.On July 7, APL ground controllers are set to fly NEAR down to 22 miles (35 kilometers) radius to Eros. In doing so, NEAR will whisk by Eros, at closest approach, about 10 miles (16 kilometers) above its dusty and cratered surface.
Ridges, troughs and boulders
Lucy McFadden, a NEAR science team member from the University of Maryland in College Park, said the NEAR navigation team presented the options for the sequence of low-altitude flyovers.
"We liked the options, even the possibilities of hovering over Eros, even though they can't hover for very long," McFadden said.
There have been a variety of features pictured by NEAR, even though it's such a small body, she said. "There are various intriguing things we're seeing. So getting closer would be useful."
For the flyovers, the science team has given a list of potential targets deserved of close-up inspection.
"Any low-altitude flyover is going to find something interesting. We want to look at the smooth floor in the area we call the Saddle. Then there are various ridges, troughs and boulders. We gave them a list of five or six things that we want to look at," McFadden said.
Southern exposure
As of June 25, NEAR was on a course that takes it over Eros' southern hemisphere. To date, most of the spacecraft's instruments were trained on the northern regions of the space rock -- terrain that was bathed in sunlight.
"We're moving into the southern hemisphere. We're looking at the other half," McFadden said.
Now NEAR can click away at the illuminated areas. "We want to see if ridges continue all the way around, from the northern hemisphere to the southern hemisphere," she said.
As for the science data being gleaned by NEAR so far, McFadden said "we're really in Fat City, I think."
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