STEERING PROBLEMS LEAVE SATELLITE IN A LOW ORBIT

CAPE CANAVERAL, Fla. (AP) - Atlantis' astronauts released a European satellite Sunday after an anxious day's delay, but the spacecraft ran into more trouble and was left wandering too low with its load of crystals, seeds and shrimp eggs.

Unless the $213 million Eureca satellite is raised to a higher altitude, its orbit will decay to the point where the craft cannot be retrieved by astronauts next spring as planned. The satellite would plunge through the atmosphere and burn up.

Engineers at the European Space Agency's control center in Darmstadt, Germany, struggled to understand the latest problem, which involved the satellite's steering system.

The solution may be as simple as sending up a computer program correction, said Eckart Graf, a program manager for the European Space Agency, which owns the satellite.

Eureca managers hoped to fire the satellite's on-board thrusters as early as Monday, provided the problem can be resolved by then, and boost the craft to its proper altitude of 320 miles.

"We consider it as a glitch in the procedure, as a delay. It's a very unfortunate one," Graf said. "However, we are optimistic and very confident that we will have a solution at hand very soon."

Eureca's ascent was interrupted shortly after Swiss astronaut Claude Nicollier freed the satellite from the end of the shuttle's robot arm 264 miles above Earth. The thruster burn was halted when the satellite appeared to be in the wrong position.

Eureca only got as high as 276 miles as a result of the six-minute burn, which was supposed to last four times that long.

The reusable satellite, a box-shaped structure with solar wings, contains brine shrimp eggs, bacteria and fungi spores, seeds, a crystal-growing furnace, a telescope, solar monitors and a cosmic dust catcher.

At 9,900 pounds and 66 feet across, it is the largest satellite ever built by the European Space Agency.

Graf said the biological samples would not be damaged at the current altitude. But the scientific studies cannot begin until the satellite is in a stable orbit. The jostling of thruster firings would ruin the experiments.

"We are taking all the time necessary to do trouble-shooting and find the solution," Graf said. "We are not under pressure."

Graf said the positioning problem was unrelated to the communications trouble with Eureca that arose just before the satellite was to be released Saturday. The data-relay problem was resolved in time for a Sunday send-off.

Eureca was supposed to spend nine months in the 320-mile-high orbit and then be lowered so Atlantis could swing by next April or May and return it for study. The European Space Agency paid $29 million to NASA for delivery and pickup; the entire Eureca project cost $428 million.

There were no plans for this Atlantis crew to go back and rescue Eureca. The shuttle and satellite were hundreds of miles apart by early afternoon.

As Eureca drifted farther and farther away, the astronauts beamed down video of the glistening satellite with a crescent moon in the background.

"That's one for Hollywood," said Mission Control's Bill McArthur.

The seven astronauts prepared for the tricky part of their mission - Tuesday's release of an Italian satellite that will be connected to Atlantis by 12 miles of electricity-generating cord.

The 30-hour experiment was supposed to be conducted on Monday and Tuesday, but was pushed back a day because of the delay in releasing Eureca.

NASA mission operations director Randy Stone said flight controllers double-checked the shuttle's data-relay system as a result of Saturday's communications trouble with Eureca to make sure everything was in order for the Tethered Satellite test.

"Until you get there I guess you never know for certain," Stone said. "But there is nothing that points to a problem related to (the Tethered Satellite) as a result of what we saw operating Eureca."

Flight directors may extend Atlantis' mission by one day because of the delay in releasing Eureca. As it is now, Atlantis is supposed to land at Kennedy Space Center on Friday, one week after liftoff.