Did the U.S. intentionally, inadvertently or even have anything to do with interfering with Russia's Phobos-Grunt Mars probe, which was launched in Nov. 2011 but failed to enter orbit and fell back to Earth last week?
On Wednesday, 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-Grunt space probe. All the while, NASA's 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.
Adding to the he-said she-said argument, Aviation Week (via Gizmodo) reported some interesting developments from the website Space Track, which is managed by U.S. Strategic Command, tracking orbiting man-made objects and providing data on these objects to more than 39,000 users on its password-protected site. Aviation Week reports that while Space Track published information about Phobos-Grunt's expected fall back to Earth on Jan. 12 and tracked its progress in the days following, it broke protocol when some information was deleted.
Aviation Week explains further:
But the military deviated from normal practice when it removed links to the spacecraft’s reentry predictions while neglecting to publish final reentry data for the defunct probe Jan. 15. Instead, the site posted a vague statement asserting Phobos-Grunt “decayed within the forecast period of 16:59-17:47” GMT.
Stratcom officials were not immediately available for comment. But the forecast period in question is likely a reference to the Jan. 12-14 predictions posted to Space Track but later removed. Currently, the only Phobos-Grunt data available on the website is a statement at the top of the main orbital-reentry page that reads, “Information regarding the Phobos-Grunt (SCC# 37872) is being accomplished in a different format. This format is different from standard entries posted to Space Track.”
Aviation Week reports that users of Space Track find the deviation from normal protocol on the site confusing:
“There are links to other recent reentries from the past 30 days, six or seven objects, including one that is slated to come down in the next day or so,” says Brian Weeden, an orbital analyst and space situational awareness expert with the Washington-based Safer World Foundation.
Weeden, a former U.S. Air Force officer who directed the Joint Space Operations Center’s orbital analyst training program, has no idea what would motivate the U.S. military to break with standard protocol for Phobos-Grunt. But he says the unusual steps taken by the military raise questions about the reliability of its data with regard to high-profile or important events such as Phobos-Grunt.
“This also appears to run counter to the expressed policy of the U.S. government to improve its data-sharing efforts on space situational awareness, and undermines efforts by other U.S. government agencies such as NASA and the State Department to communicate with the public and other countries on reentries,” Weeden says.
While the Russians look into the possibility of a U.S. radar system messing with their probe's launch, U.S. experts have suggested looking for failure problems at home first.
"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.
New Scientists has considered the feasibility of U.S. radar interfering with the probe but the expert it quotes says the likelihood of this happening is slim:
According to Boris Smeds, a former radio engineer at the European Space Agency, it is highly unlikely. Deep space communications, such as those you would expect Phobos-Grunt to use, use different frequencies from those of space-observation radars, and spacecrafts' receivers are built to filter out unwanted frequencies. It is just conceivable that a badly filtered radio receiver on Phobos-Grunt was damaged by a radar beam from the US military base, but it is extremely unclear how that damage could affect the power system of the spacecraft.
Smeds conceded that it could interfere with radio reception, temporarily "deafening" a spacecraft. Still though, the firing of Phobos-Grunt's upper stage was supposed to be automatic, pre-programmed into the spacecraft before launch, so would not have relied on receiving a radio signal.
New Scientist reports that the findings from the Russian investigation are due to the public on Jan. 26. Perhaps there will be more answers to what really happened to the probe then.
The Associated Press contributed to this report.