On March 14, the ExoMars mission successfully lifted off on a 7-month journey to the planet Mars but not without a little surprise. The Breeze-M upper booster stage, designed to give the craft its final kick toward Mars, exploded shortly after parting from the probe. Thankfully, it wasn’t close enough to damage the spacecraft.
Michel Denis, ExoMars flight director at the European Space Operations, Center in Darmstadt, Germany, said that the two craft were many kilometers apart at the time of the breakup, so the explosion wouldn’t have posed a risk. Still, the mission team won’t be 100% certain until all the science instruments are completely checked over in the coming weeks.
All went well during the takeoff and final separation of the probe, but then something odd happened. Breeze-M was supposed to separate cleanly into two pieces — the main body and a detachable fuel tank — and maneuver itself to a graveyard or “junk” orbit, where rockets and spacecraft are placed at the end of their useful lives, so they don’t cause trouble with operational satellites.
But instead of two pieces, tracking photos taken at the OASI Observatory in Brazil not long after the stage and probe separated show a cloud of debris, suggesting an explosion occurred that shattered the booster to pieces.
It wouldn’t be the first time a Russian Breeze-M blew up.
According to Russian space observer Anatoly Zak in a recent article in Popular Mechanics, a Breeze-M that delivered a Russian spy satellite into orbit last December exploded on January 16. Propellant in one of its fuel tanks may not have been properly vented into space; heated by the sun, the tank’s contents likely combusted and ripped the stage apart. A similar incident occurred in October 2012.
[...]
Last week, the European Space Agency (ESA) and its Russian partners celebrated a historic launch as the long-awaited ExoMars spacecraft headed off to the Red Planet to search for potential signs of life. The 4.3-ton dual spacecraft, including the Trace Gas Orbiter which will stay in orbit as well as the lander named Schiaparelli, blasted off on March 14 from the Baikonur Cosmodrome in Kazakhstan on a Russian Proton rocket.
After the launch reached the initial parking orbit around the Earth, the Proton's fourth stage (known as Briz-M, Russian for "breeze") acted as a space tug, boosting the space probe on a path to Mars with four engine firings. What happened next was a close call that could have ended the mission catastrophically. And ExoMars still isn't out of the woods.
Shortly after the separation between ExoMars and the spent Briz-M, the probe called home, and the ground control center in Darmstadt, Germany, confirmed the mission was on a path to Mars. However, astronomers tracking the flight soon spotted a cloud of debris accompanying ExoMars in space. As many as six large pieces of space junk appeared on the photos taken by the OASI observatory in Brazil.
This was strange. For one thing, the Briz-M was supposed to separate cleanly in one large piece without producing any additional fragments. Secondly, and more importantly, after the separation the space tug was programmed to fire twice to propel itself to a safe disposal orbit as far away from its former cargo as possible. The resulting "graveyard" trajectory would ensure that the "blind and deaf" space tug, now drifting through interplanetary space, would not come anywhere near Mars, where it could contaminate the planet's pristine environment with Earth's bugs. (Unlike Mars landers, rocket stages are not sterilized in accordance with strict international standards.)
According to sources in the Russian space industry, the first of Briz-M's two collision-avoidance maneuvers was to last around 12 seconds. Once it was a safe distance from ExoMars, the rocket stage would fire again, this time for around 1.5 minutes, until the engine consumed all the remaining explosive propellant aboard. Upon completion of the second maneuver, valves would open to vent the high-pressure gas used to force propellant into the engines.
That's what's supposed to happen. The initial info available to Russian tracking experts after the launch of ExoMars indicated that Briz-M had worked as planned. But the latest tracking photos indicate that something happened before the spacecraft had had a chance to go into its graveyard orbit. The situation is complicated by the fact that Russia had no tracking means in the Western section of the Southern hemisphere, over which Briz-M was suppose to perform its maneuvers. The Russian Academy of Sciences previously had agreements to use tracking telescopes in Australia and Bolivia, but both facilities were apparently out of commission at the time of the ExoMars launch.
And history includes a few examples of the Briz-M's going wrong after launch. A Briz-M that delivered a secret military satellite into orbit on December 13 then exploded on January 16. It continues to sporadically eject gas from its damaged tanks, tracking experts say. A careful analysis of visible debris from that disaster suggests that one of the high-pressure tanks on the stage was sheered off. The most likely explanation for that is the failure to vent its gas and propellants into space. Sunlight could have heated up contents, triggering an explosion.
What is especially worrying about the latest accident is that Briz-M apparently exploded after just 10.5 hours in space, when its ExoMars cargo was still in the vicinity. The good news is that ExoMars appears to be undamaged by whatever happened to its space tug, but the mission is not out of the woods yet.
[...]
Maybe it would be better if they get to the planet and destroyed by atmosphere, otherwise they could be a threat for future missions being on a heliocentric orbit, what do you think?
The worst possible (but very unlikely) scenario would be that a terrestrial bacteria survives the trip and settles on Mars. That's not going to create evil martian mutants but then it would ruin a lot of scientifical efforts on the search on life on Mars.
On a more plausible perspective, ExoMars is mostly devoted to atmospheric research, and droplets of rocket propellant on the sensors would be really bad. This is what concerns me the most.
You posted this quote:...Sources don't mention how far away ExoMars was from Briz during the explosion.
...Michel Denis, ExoMars flight director at the European Space Operations, Center in Darmstadt, Germany, said that the two craft were many kilometers apart at the time of the breakup, so the explosion wouldn’t have posed a risk...
You posted this quote:
14 April 2016
The ESA–Roscosmos ExoMars spacecraft are in excellent health following launch last month, with the orbiter sending back its first test image of a starry view taken en route to the Red Planet.
In the weeks following liftoff on 14 March, mission operators and scientists have been intensively checking the Trace Gas Orbiter (TGO) and the Schiaparelli entry, descent, and landing demonstrator to ensure they will be ready for Mars in October.
In order to precisely deliver the Schiaparelli landing demonstrator module to the martian surface and then insert ExoMars/TGO into orbit around the Red Planet, it’s necessary to pin down the spacecraft’s location to within just a few hundred metres at a distance of more than 150 million km.
To achieve this amazing level of accuracy, ESA experts are making use of ‘quasars’ – the most luminous objects in the Universe – as ‘calibrators’ in a technique known as Delta-Differential One-Way Ranging, or delta-DOR.
28 July 2016
Following a lengthy firing of its powerful engine this morning, ESA’s ExoMars Trace Gas Orbiter is on track to arrive at the Red Planet in October.
ExoMars made its first critical manoeuvre since its 14 March launch this morning, firing its engine for 52 minutes to help it intercept Mars on 19 October.
11 August 2016
Schiaparelli, the Entry, Descent and Landing Demonstrator Module of the joint ESA/Roscosmos ExoMars 2016 mission, will target the Meridiani Planum region for its October landing, as seen in this mosaic created from Mars Express images
British mapping agency Ordnance Survey (OS) has released an easy-to-read map of terrain from the planet Mars.
Open data published by Nasa was used to make the map, which has been posted on the OS Flickr account.
This is the first time that OS has produced a map of territory from another planet.