January 2, 2012
Mars Moon Probe To Return To Earth Next Week
The Russian probe that was to explore Mars' moon Phobos before becoming stranded in orbit is expected to fall back to Earth sometime next week, various media outlets are reporting.
Early last week, European Space Agency (ESA) space debris chief Heiner Klinkrad told Space.com columnist Leonard David that current re-entry forecasts predict that the Phobos-Grunt satellite, which was launched on November 9, could plummet through Earth's atmosphere on January 14 or 15, plus or minus five day.
Approximately 20 to 30 fragments of the nearly 14 ton probe are expected to survive re-entry and hit the Earth's surface at that time, Seattle Post-Intelligencer blogger Amy Rolph added on Wednesday. Those pieces could weigh a total of up to 400 pounds and will "probably crash into oceans or undeveloped land," she added.
Shortly after its launch, Phobos-Grunt found itself stuck in orbit around our planet after its rocket boosters failed to fire. Shortly afterwards, computer malfunctions prevented ground control to communicate with the probe, save for a brief period in late November.
The craft was to explore the Martian moon and bring back rock samples for study. Ultimately, however, the Russian national space agency (Roscosmos) was forced to abandon the mission, Guardian Science Correspondent Ian Sample wrote in a January 1 article.
"Space agencies tracking the rocket from radar stations around the world have stepped up their monitoring to once every day," Sample reported. "As the spacecraft nears re-entry, officials will track its descent hour by hour to improve predictions of where any debris might land."
"Tracking Phobos-Grunt will allow space agencies to work out when the rocket will begin re-entry, but does little to help predict where debris might land," he added. "The spacecraft is travelling so fast it completes an orbit of Earth every 90 minutes, so even a small uncertainty in its trajectory or how it breaks up can make a difference of hundreds of miles on the Earth's surface."
Despite initial concern that the toxic fuel on board Phobos-Grunt, identified by the Guardian as unsymmetrical dimethylhydrazine (UDMH) and dinitrogen tetroxide (DTO), could lead to contamination of the crash site and a potential environmental disaster, Klinkrad said that the probe's re-entry "will not be“¦ very high risk."
"[The fuel is] a very delicate structure and it will break up fairly quickly. Largely it consists of propellant to take it to Mars, which is still left in the tank, and none of that is expected to survive re-entry," he added.
Image Caption: A Zenit rocket with Phobos-Grunt is being erected onto the launch pad on November 6.
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