Russia will look into the possibility that a U.S. radar station could have inadvertently interfered with the failed Mars moon probe that plummeted to Earth, Russian media reported Tuesday, but experts argued that any such claims were far-fetched.
NASA spokesman Bob Jacobs also said the U.S. space agency was not using the military radar equipment in question at the time of the Russian equipment failure, but instead was using radar in the Mojave desert in the western United States and in Puerto Rico.
Russia's state news agency RIA Novosti quoted Yury Koptev, former head of the Russian space agency Roscosmos, as saying investigators will conduct tests to check if U.S. radar emissions could have impacted the Phobos-Ground space probe, which was stuck in Earth's orbit for two months before crashing down near Chile and Brazil.
"The results of the experiment will allow us to prove or dismiss the possibility of the radar's impact," said Koptev, who is heading the government commission charged with investigating causes of the probe's failure.
U.S. experts suggested that the Russians should look for causes of the failure at home.
"The Russian Space Agency would do themselves and the future of Russian planetary exploration some good to look inside the project and the agency to find the cause of the Phobos-Ground mishap," said Alan Stern, former associate administrator for science at NASA and now director of the Florida Space Institute at the University of Central Florida.
The current Roscosmos head, Vladimir Popovkin, has said the craft's malfunction could have been caused by foreign interference. Deputy Prime Minister Dmitry Rogozin acknowledged U.S. radar interference as a possible cause but said it was too early to make any conclusions and suggested the problem could be the spacecraft itself.
"Practially all disruptions are due to flaws in the technologies manufactured 12 to 13 years ago," he said.
Other space experts said the possibility of U.S. interference should be considered only after investigating all other possible causes.
Alexander Zakharov, a specialist at the Space Research Institute, which developed the Phobos-Ground, called the suggestion "contrived" and doubted the United States has radar powerful enough to interfere with a spacecraft at an altitude of around 200 kilometers (124 miles).
"You can come up with a lot of exotic reasons," Zakharov told RIA Novosti. "But first you need to look at the apparatus itself, and there is a problem there."
The Phobos-Ground fell to Earth on Sunday in the vicinity of Chile and Brazil, but no confirmed impact sites have been reported.
The $170 million craft was one of the heaviest and most toxic pieces of space junk ever to crash to Earth, but space officials and experts said the risks posed by its crash were minimal because the toxic rocket fuel on board and most of the craft's structure would burn up in the atmosphere high above the ground anyway.
The Phobos-Ground probe was designed to travel to one of Mars' twin moons, Phobos, land on it, collect soil samples and fly them back to Earth in 2014 in one of the most daunting interplanetary missions ever. It got stranded in Earth's orbit after its Nov. 9 launch, and efforts by Russian and European Space Agency experts to bring it back to life failed.
Phobos-Ground was Russia's most expensive and the most ambitious space mission since Soviet times. Its mission to the crater-dented, potato-shaped Martian moon was to give scientists precious materials that could shed more light on the genesis of the solar system.
Russia's space chief has acknowledged the Phobos-Ground mission was ill-prepared, but said that Roscosmos had to give it the go-ahead so as not to miss the limited Earth-to-Mars launch window.
Associated Press writer Seth Borenstein contributed to this report from Washington, D.C.