No chance now to save Phobos-Grunt Mars mission
Duff Russian probe continues to stubbornly circle Earth
The window to contact the stranded Phobos-Grunt and send it on its mission to the Martian moon has now closed.
The craft could still fly by the Red Planet, but it will no longer be able to complete its exploration of the Martian moon Phobos and return to Earth, space industry sources told Russian state news agency RIA Novosti.
Over the last two weeks, there was no clear response from attempts to get in contact with the Mars probe, which got stuck in Earth's orbit when its engines failed to fire and send it on its way to the Red Planet.
If Russia wants to try again to get a spaceship to Mars, or indeed has the billion or so rubles it will need to try again, the next opportunity will be 2014.
Russian space boffins have been trying for weeks to rescue the Phobos-Grunt, which launched successfully but never set out from Earth's orbit on its mission.
The attempt was always something of a long shot, since establishing any contact was difficult given the small windows during which it was in range of an earth-to-space communication centre, and even if they got in touch, there was no guarantee they could get the engines going.
A Russian space expert said last week that if the probe failed to get to Mars, the space agency should still keep trying to get in touch because it could maybe make it to Earth's Moon instead.
Failing that, just getting the craft to land on Earth instead of crashing through the atmosphere could allow the agency to recover equipment from the ship and even readings from its instruments.
If all attempts to contact the Phobos-Grunt fail, it will eventually fall out of Earth's orbit and crash through the atmosphere.
Vladimir Popovkin, head of the Russian space agency, has dismissed fears that it could crash into civilian areas, saying that the 7.5 metric tonnes of fuel aboard the craft in aluminium tanks would ensure it exploded on re-entry.
However, earlier today a source told RIA Novosti that some heat-resistant parts of the probe could fall to earth.
Russian space sources have also variously given the Phobos-Grunt until December, January or even March to fall out of the sky. ®
Just send up a Space Shuttle on a recovery mission and... Oh wait... Forgot about them canceling that program.
Maybe the military can use a space based target for their High Energy Weapons Tests.
Andus, it is possible to escape the earth's gravity without reaching escape velocity, going "slowly" as you say. However, this would be much less fuel efficient, since most of the fuel would be spent on the hovering portion instead of propelling the craft further from earth. Moreover, since more fuel would have to be burnt at higher altitude in order to keep the craft hovering, that same fuel would have to be carried along, requiring even more fuel to be carried through the lower altitudes. Below a certain speed, this would become impossible with conventional rockets, as the thrust of the rockets would be unable to lift the amount of fuel required from the ground. So, yes with a yet-to-be-invented light anti-gravity device with near infinite energy, you could slowly rise into orbit. Until then, we need to boost the rocket to escape velocity as low down as possible, burn up almost all the fuel (except that required later for maneuvering) and jettison the spent engine for additional weight loss.
The spacecraft contains an amount of fuel to provide it with a Delta-V (change of velocity) sufficient to reach escape velocity plus a bit more.
The craft currently has an orbital velocity of about 28000 kph. It needs about 40000 to attain escape velocity. If it were possible to use the engines in a braking maneuver instead (it isn't) then the most it could reduce velocity is to a mere 12000 kph. Reentry would then take place at *only* around mach 10 or so (instead of mach 25). Not enough to turn it into plasma but far more than enough to melt most of the components and shred it into confetti before it explodes. It has the aerodynamic qualities of a bird's nest attached to a brick of C4..