Rescuers admit it's a long shot, but a robotic camera dropped deep inside a Utah mountain could be the best chance officials have of finding any sign of six men missing for 21 days after a caved-in at a coal mine.

The 8-inch robot was to be lowered more than 1,500 feet through a narrow hole to scope out the "survivable space" inside the mine Sunday, although mine executives, safety officials and technology experts estimate the chances of success at less than 50 percent.

"It's a long shot, and I repeat, it's a long shot. But we owe it to the families to do everything we can to locate their loved ones," said Jack Kuzar, a district manager for the federal Mine Safety and Health Administration.

The camera arrived Friday and was tested over the weekend before plans to lower it into the mine Sunday night. Images from the camera were expected sometime Monday.

The camera is similar to the one used to search within the wreckage of the World Trade Center in New York City after the Sept. 11, 2001, terrorist attacks. It is programmed to take images in the darkened cavern from about 50 feet away with the help of a 200-watt light, can travel 1,000 feet from the end of the test hole and has some ability to move around the rubble.

Robin Murphy, director of the Institute for Safety Security Rescue Technology at the University of South Florida, said it was not clear if the 8-inch camera would fit down the 8 5/8-inch hole and into the mine, much less make it past the loose rock and other debris in the borehole.

"There's mud, there's rocks, there's things that make it unfavorable," she said.

But the brother of one of the missing miners said families were hopeful.

"We've got a lot to learn from the camera and we're all hoping it will do a good job for us," Cesar Sanchez said.

The camera was being lowered into one of six bore holes drilled through the mountain since Aug. 6, when a thunderous mountain bump caused the ribs of the mine shaft to explode, leaving miners Kerry Allred, Don Erickson, Luis Hernandez, Carlos Payan, Brandon Phillips and Manuel Sanchez trapped inside. It's unclear if the men survived the blast.

Officials also began drilling a seventh hole Sunday, hoping to break into the mine's "kitchen," an area where miners are trained to find safety during a collapse. The area is about 1,800 feet below the surface, and while mine bosses would not estimate a timetable for completion, previous drilling efforts have taken up to two days.

"Everybody, you know, was kind of smiling a little bit about the seventh hole," Sanchez said. "It brings the hope back up. We needed that and we're going to keep going until we find these guys."

Families had expected officials to halt rescue efforts Sunday, after mine co-owner Bob Murray said earlier he would shutter the mine and entomb the men if the sixth hole found no sign of life.

That announcement followed a second collapse Aug. 16 that killed three people and wounded six who were digging horizontally through massive mounds of debris inside the mine.

Federal mining officials have said the instability of the mountain makes it too risky to resume underground digging or to drill a hole wide enough to send a manned rescue capsule into the mine, something families have called for.

Seismologists describe the mountain as crumbling in upon itself, bursting support pillars as the rock shifts.

Also Monday, the state's new Mine Safety Commission met for the first time. Gov. Jon Huntsman told the panel that he wanted members to determine whether Utah should take over safety regulation of the state's 13 coal mines. A report is expected in the fall.

Utah surrendered oversight of mine safety in 1977 to the federal government. At the time, Utah had only three safety inspectors for all its coal and hard-metal mines, said Sen. Mike Dmitrich, D-Price, a member of Huntsman's panel.

The mining industry provides the economic backbone of eastern Utah's Emery and Carbon counties, where mines have been part of the landscape since the early 1900s and generations of men and women follow their relatives underground.

Since the collapse, the small, tight-knit communities here have poured out support for the families of the trapped, killed and injured men in a series of fundraising events.

Family spokesman Sonny Olsen said all of the money collected is being given to the miners' families and will not be used for any legal expenses, even though the families have retained attorneys.

Also Monday, the first meeting of the new Utah Mine Safety Commission was scheduled. The commission was organized last week by Gov. Jon Huntsman. He has charged the committee with investigating the mine accident and looking for ways to prevent future accidents.