Scientists watching the arrival of the first close-up image of Mars from the University of Arizona's HiRISE camera Friday afternoon said the picture exceeded their expectations. But they said it's too early to draw conclusions about the geologic processes that formed the remarkably clear features visible in the photograph.

"If you were there, we could see you," said Alfred McEwen, principal investigator on the High Resolution Imaging Science Experiment, about the resolution, or level of detail, of the digital pictures taken by the camera, developed at the UA.

HiRISE is, essentially, a camera using 14 chips not unlike those in consumer digital cameras, but with a telescope for a lens. It's one of six instruments aboard the Mars Reconnaissance Orbiter, or MRO.

McEwen, pointing out details on a 30-inch widescreen computer monitor in the HiRISE Operation Center on the UA campus, HiROC, said the some of the smallest features visible were about the size of a filing cabinet.

That resolution is crucial as checking out landing sites for the Phoenix Mission's lander, set to launch in August 2007 and set down on Mars in May 2008, is at the top of the HiRISE camera's to-do list. McEwen said earlier this week that, until HiRISE, orbiting cameras haven't had the resolution to pick out objects, such as boulders, that would make a lander touchdown unsafe.

The first image, taken from about 200 miles up of an area about 650 yards wide, was 2,000 pixels wide with each pixel representing about a foot of Mars, said McEwen.

The area, Ius Chasma, part of the Valles Marineris — Mars' Grand Canyon — is near the planet's equator.

McEwen says it was chosen because it was an area of known geologic interest that happened to be in the camera's path on its first orbit.

The image showed areas that appeared to be dunes and others that looked like like they had been formed by flowing water.

Nearby were a series of craters, roughly 75 feet in diameter.

Another section showed what looked like a cliff bisected by a fault line. The two sections of the cliff appeared to be offset at the fault by roughly 300 feet.

There were also many relatively small craterlike impressions.

Lisa McFarlane, a HiRISE targeting specialist, said it wasn't possible to draw solid conclusions about the area without more information. She said some of that information will come from the other imaging and remote-sensing devices on MRO. She said when more information is needed, coordinated observations will be set up so that HiRISE and one or more of the other MRO devices can take images of the same areas.

HiRISE information is expected to begin arriving in a fairly constant stream as the camera photographs roughly 1 percent of the planet's surface in its first year of operation as it passes high above the planet in a polar orbit — roughly from pole to pole as the planet spins below.

The first picture released to the public, a very small part of the total first image, is in black and white. McEwen said the images would be processed later to reveal color. He said the HiRISE camera can only produce color from chips in the middle of the elongated 14-chip array.

The mood in the command center was partylike, with team members moving between computer screens as sections of the first image were magnified and examined.

Scientists no longer have to wait weeks for images to be sent back from planetary missions and processed, as in earlier days of the space program. Unlike early space cameras, HiRISE provides almost instant gratification.

And with photos from Mars posted on the Internet within hours of when they're received, HiRISE is in some ways a space webcam.

Soon it will become an interactive space webcam.

McEwen says the HiRISE team intends take public requests for areas to have HiRISE — aka "The People's Camera" — photograph on Mars.

The crowd at HiROC was a mix of veteran planetary scientists and young students, including some undergraduate students.

"A lot of people, you look at their faces and it's like a kid at Christmastime," said Ben Pearson, a HiRISE team computer programmer and UA electrical engineering major.

"I'm going to be missing class," Pearson said as he decided to stick with the imaging group effort.

"It's incredible," Pearson said of the quality of the images. "We knew somewhere in our minds that this was what it was capable of. But, when you actually see it …"

On StarNet: For a photo slideshow of the HiRISE images, visit azstarnet.com/ slideshows

● View and download Mars photos taken by HiRISE at the HiRISE Operations Center (HiROC) Web site: hiroc.lpl.arizona.edu

"It's incredible. We knew somewhere in our minds that this was what it was capable of. But, when you actually see it …"