Explosion Leaves Questions and Dead Mosquito Eggs

No people were hurt when a rocket taking supplies to the International Space Station exploded just after launching on Tuesday night - but the mosquito eggs did not survive.

Julia Ellis, 13, was across the bay from the launching pad on Wallops Island, Virginia, less than 2 miles away, watching as the rocket lifted off. Amid the 5,000 pounds of cargo was an experiment that she and four classmates at Columbia Middle School in Berkeley Heights, New Jersey, had devised to study whether mosquito larvae can grow in zero gravity.

"Everyone was just so excited and happy," she said. "You could hear everyone cheering."

Then there was a flash, and the rocket fell. "It feels like someone smacked you in the chest," she said. "You hear one small explosion, one really large explosion and then two small explosions."

On Wednesday, investigators started looking through the wreckage of the Antares rocket, built by the Orbital Sciences Corp. of Dulles, Virginia, one of two private companies that NASA relies on to take cargo to the station. Four previous Antares launches, three of which went to the space station, were successful.

During a conference call with financial analysts, David W.

Thompson, Orbital's chairman and chief executive, said the rocket experienced a catastrophic failure about 15 seconds after liftoff, destroying the rocket and its payload. "It appears that the launch complex itself was spared from any major damage," he said.

Garrett E. Pierce, the company's chief financial officer, said the failure would not affect the company's finances this year, because insurance would cover repairs to the launching site and the payments from NASA that might be held back.

Orbital has a $1.9 billion contract from NASA for eight cargo flights, or $237 million each.

NASA officials said the loss would have no immediate effect on the operations of the space station, which has several months of supplies. A Russian cargo rocket successfully launched on Wednesday, as scheduled, and docked at the space station six hours later.

Among the items lost in the Antares explosion were a suite of student experiments arranged by NanoRacks, a small company in Houston that flies commercial payloads to the space station. Also lost were 29 nanosatellites, the largest weighing about 22 pounds, that the company had arranged to be launched from the space station.

Jeffrey Manber, NanoRacks' managing director, spent the day like an airline customer service agent trying to rebook passengers from a canceled flight.

"We're sitting here right now working through the needs of our customers," Manber said. "What are the priorities of the payloads? Who can rebuild? Who's ready to go?"

SpaceX, the other company that NASA has hired to ferry cargo, completed its most recent flight to the station last week, and its next rocket is scheduled to launch in December. Manber said some of the rebuilt student experiments could be on that flight.

Thompson said he expected that the next Antares launch, set for April, would be delayed by several months.

While he said it was too early to speculate on why the Antares crashed, Thompson added: "It will likely not take very long - I think a period measured in days, not weeks - for the investigation team to define the handful of most likely causes of the accident. It may take a little longer than that to zero in on the final root cause."

Certain to be scrutinized are the two engines in the rocket's first stage. They were built in the Soviet Union in the late 1960s and early 1970s to power a giant rocket to go to the moon. After NASA's successful moon landings, the Soviets abandoned their effort, and the engines lay in storage for decades.

Then a U.S. company, Aerojet, bought and refurbished them, and Orbital incorporated them into the Antares design.

One of the engines failed during testing in May, delaying the previous Antares flight. Orbital officials said the company was considering accelerating its plans to replace the old Soviet engines.

Orbital has had two other high-profile NASA failures in recent years.

In 2009, NASA's Orbiting Carbon Observatory on top of Orbital's Taurus XL rocket was lost when the nose cone protecting the satellite failed to separate, and the satellite crashed into the ocean.

Two years later, a similar failure destroyed NASA's Glory satellite, which was to have made climate observations.