[meteorite-list] Russia: Computer Crash Doomed Phobos-Grunt

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue, 7 Feb 2012 09:47:35 -0800 (PST)
Message-ID: <201202071747.q17HlZH3008485_at_zagami.jpl.nasa.gov>

http://www.spaceflightnow.com/news/n1202/06phobosgrunt/

Russia: Computer crash doomed Phobos-Grunt
BY STEPHEN CLARK
SPACEFLIGHT NOW
February 6, 2012

After floating accusations against U.S. military radars, flawed foreign
parts and space radiation, Russian space officials have concluded a
software glitch caused the failure of the Phobos-Grunt Mars probe.
 
The commission investigating the mishap says Phobos-Grunt's $165 million
mission was halted by "a programming error which led to a simultaneous
reboot of two working channels of an onboard computer," according to RIA
Novosti, a Russian news agency.

The reboot put the spacecraft in safe mode, according to the report
released by Roscosmos, the Russian space agency. The probe went into a
sun-pointing orientation to maintain an electrical charge and await
further commands, Roscosmos officials said.

The problem struck shortly after the Phobos-Grunt spacecraft launched
Nov. 8. A Zenit rocket boosted the hefty payload into low Earth orbit,
then two more rocket firings were planned several hours later to propel
the probe toward Mars.

But the craft's rocket pack never fired because of the computer reboot,
leaving the craft stranded in orbit several hundred miles above Earth.
Russian engineers were unable to establish contact with Phobos-Grunt
again, and except for two brief communications sessions with a European
Space Agency ground station, the satellite remained silent.

Tracking data indicated Phobos-Grunt raised its orbit in the days
following the anomaly, and information shows the spacecraft changed its
altitude at least 10 times, according to Ted Molczan, a respected
satellite observer based in Canada.

Molczan said the orbit maneuvers were "almost certainly" from thrusters
designed to control the probe's attitude and settle propellant before
the two burns of the craft's main engine to guide Phobos-Grunt to Mars.

The orbit change observed by U.S. military tracking assets was roughly
equivalent to 22 ullage, or propellant-settling, thruster firings as
they were planned under the mission's normal launch scenario, Molcan
posted on Satobs.org, a website for satellite tracking hobbyists.

The data could be evidence the spacecraft repeatedly tried to fire its
rocket engine and aim for Mars.

Vladimir Popovkin, head of Roscosmos, told Russian reporters radiation
damage could have caused the unexpected computer crash.

Former Planetary Society executive director Louis Friedman said
Phobos-Grunt's orbit was below the radiation belts surrounding Earth,
placing that explanation in doubt.

The root cause listed in the official failure report was the use of
computer components not qualified for spaceflight.

"Cheap parts, design shortcomings, and lack of pre-flight testing
ensured that the spacecraft would never fulfill its goals," Friedman
wrote in a posting on the Planetary Society website.

Friedman managed a Planetary Society experiment in which microbes from
Earth were launched on Phobos-Grunt to study how basic life forms can
weather an interplanetary voyage. He also has close ties with officials
at NPO Lavochkin, Phobos-Grunt's prime contractor.

Loaded with more than 11 tons of rocket propellant, Phobos-Grunt crashed
back to Earth on Jan. 15. Most of the craft burned up in the atmosphere
over the Pacific Ocean west of Chile.

Russia commissioned investigators, led by former Russian space agency
director Yuri Koptev, to look into the failure beginning in December.
The board submitted their findings to Roscosmos on Jan. 30, and a
summary was published on the Roscosmos website Feb. 3.

Koptev told Russian media in January that U.S. military radars in the
Pacific Ocean could have frazzled Phobos-Grunt's computer, but officials
later backed away from that accusation.

Phobos-Grunt was designed to release a small Chinese satellite in orbit
around Mars, then retrieve samples from Phobos, the red planet's largest
moon. The material was to be returned to Earth in 2014.
Received on Tue 07 Feb 2012 12:47:35 PM PST