Posts Tagged ‘ESA’

Update: ESA’s Schiaparelli destroyed by 300km/h impact

October 21, 2016

ESA has now confirmed that pictures from NASA’s Mars Reconnaissance Orbiter now show that Schiaparelli was destroyed on impact.

ESA:

Schiaparelli entered the martian atmosphere at 14:42 GMT on 19 October for its 6-minute descent to the surface, but contact was lost shortly before expected touchdown. …..  

……. Estimates are that Schiaparelli dropped from a height of between 2 and 4 kilometres, therefore impacting at a considerable speed, greater than 300 km/h. The relatively large size of the feature would then arise from disturbed surface material. It is also possible that the lander exploded on impact, as its thruster propellant tanks were likely still full. These preliminary interpretations will be refined following further analysis.

Reuters:

Images taken by a NASA Mars orbiter indicate that a missing European space probe was destroyed on impact after plummeting to the surface of the Red Planet from a height of 2-4 km (1.2 to 2.5 miles), the European Space Agency said on Friday.

The disc-shaped, 577-kg (1,272 lb) Schiaparelli probe, part of the Russian-European ExoMars program to search for evidence of life on Mars, descended on Wednesday to test technologies for a rover that scientists hope to send to the surface of the planet in 2020.

But contact with the vehicle was lost around 50 seconds before the expected landing time, leaving its fate uncertain until the NASA images were received.

“Schiaparelli reached the ground with a velocity that was much higher than it should have been, several hundred kilometers per hour, and was then unfortunately destroyed by the impact,” ExoMars Flight Director Michel Denis told Reuters TV.

It was only the second European attempt to land a craft on Mars, after a failed mission by the British landing craft Beagle 2 in 2003.

The U.S. space agency’s Mars Reconnaissance Orbiter, which has been circling the planet for about 10 years, took low-resolution pictures that show a bright spot that ESA believes is the 12-metre parachute that Schiaparelli used to slow down. They also show a fuzzy dark patch, around 15 by 40 meters in size, about 1 km north of the parachute, which scientists interpret as having been created by the impact of the lander following a longer-than-planned free fall.

The ESA/NASA  plan to put a rover on Mars by 2021 (ExoMars Rover) is likely to be delayed considerably. NASA is also looking at another project to launch in 2020 and land a rover on Mars perhaps in 2022.

The Indian/Russian plan with Chandrayan 2 to put a lunar rover onto the moon is still on the cards for 2019.


 

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Second European Mars lander (Schiaparelli) also lost (after Beagle 2 in 2003)

October 20, 2016

While the ExoMars Trace Gas Orbiter by the European/Russian space agencies (ESA/Roscosmos) seems to have successfully entered the correct orbit around Mars, ESA’s Mars lander, Schiaparelli seems to have been lost on its way down to the surface.

schiaparelli-descent image-esa

schiaparelli-descent image-esa

BBC: 

There are growing fears a European probe that attempted to land on Mars on Wednesday has been lost. Tracking of the Schiaparelli robot’s radio signals was dropped less than a minute before it was expected to touch down on the Red Planet’s surface.

Satellites at Mars have attempted to shed light on the probe’s status, so far without success. One American satellite even called out to Schiaparelli to try to get it to respond. The fear will be that the robot has crashed and been destroyed. The European Space Agency, however, is a long way from formally calling that outcome. Its engineers will be running through “fault trees” seeking to figure out why communication was lost and what they can do next to retrieve the situation.

This approach could well last several days. 

One key insight will come from Schiaparelli’s “mothership” – the Trace Gas Orbiter (TGO). As Schiaparelli was heading down to the surface, the TGO was putting itself in a parking ellipse around Mars. But it was also receiving telemetry from the descending robot.

If the lander is indeed lost, it will be the second failure of a European Mars lander after the failure of Beagle 2 in 2003.

Beagle 2 was a British landing spacecraft that formed part of the European Space Agency’s 2003 Mars Express mission. The craft lost contact with Earth during its final descent and its fate was unknown for over twelve years. Beagle 2 is named after HMS Beagle, the ship used by Charles Darwin.

The spacecraft was successfully deployed from the Mars Express on 19 December 2003 and was scheduled to land on the surface of Mars on 25 December; however, no contact was received at the expected time of landing on Mars, with the ESA declaring the mission lost in February 2004, after numerous attempts to contact the spacecraft were made.

Beagle 2‘s fate remained a mystery until January 2015, when it was located intact on the surface of Mars in a series of images from NASA’s Mars Reconnaissance Orbiter HiRISE camera. The images suggest that two of the spacecraft’s four solar panels failed to deploy, blocking the spacecraft’s communications antenna.

The ESA’s plans and budget for landing a six-wheeled roving vehicle on Mars in 2021 will face further critical scrutiny. The rover is expected “to use some of the same technology as Schiaparelli, including its doppler radar to sense the distance to the surface on descent, and its guidance, navigation and control algorithms”.

ESA has an annual budget of about €5.25 billion.

Of course the EU sees the ESA as a matter of prestige first (and science, only second) which does help to protect the budget.

Perhaps some “frugal engineering” (a la ISRO) is called for.


 

Rosetta finds its new stone

August 8, 2014

The Original Rosetta Stone – BBC

The new stone is a comet identified as 67P/Churyumov-Gerasimenko

  • It was first observed in 1969 and named after its Russian discoverers
  • The comet is in an elliptical 6.45-year orbit that takes it from beyond Jupiter at its furthest point, to between the orbits of Mars and Earth at its closest to the Sun.
  • It is approximately 3.5 x 4 km in size, has a rotational period of 12.7 hours and a mass of 3.14±0.21×1012 kg
  • The surface temperature appears to be around -70ºC, which is warmer than expected
  • It is currently about 405 million km from earth (about 22.5 light-minutes) and moving at 55,000 km/hr

The European Space Agency’s Rosetta craft has now arrived at 67P/Churyumov-Gerasimenko after a 10 year, 6.4 billion km long journey and has entered orbit around its new stone

Rosetta is a cornerstone mission to chase, go into orbit around, and land on a comet. It will study the Jupiter-family comet 67P/Churyumov-Gerasimenko with a combination of remote sensing and in situ measurements. The spacecraft will orbit the comet and release the Philae lander, which carries a suite of instruments for imaging and sampling the comet nucleus. The mission will track the comet through perihelion, examining its behaviour before, during and after.

Rosetta Trajectories by Christian Simoes astronoo.com

Rosetta Trajectories by Christian Simoes astronoo.com

The spacecraft was launched from Kourou aboard an Ariane 5G+ on 2 March 2004. It required four gravity assists for its journey, one by Mars and three by Earth. Rosetta had already flown by the asteroids 2867 Steins (in 2008) and 21 Lutetia (in 2010), before entering deep space hibernation in June 2011.

Rosetta’s main goals will be reached in 2014. Following a planned exit from hibernation on 20 January, the spacecraft’s instruments were checked as it continued on its journey to 67P/Churyumov-Gerasimenko. The spacecraft arrives at the comet in August 2014, and deploys the lander in November 2014.

Comet 67P-CG on 3rd August 2014 ESA

Comet 67P-CG on 3rd August 2014 ESA

Rosetta is just 100 km from the comet’s surface, but it will edge closer still. Over the next six weeks, it will describe two triangular-shaped trajectories in front of the comet, first at a distance of 100 km and then at 50 km.

At the same time, more of the suite of instruments will provide a detailed scientific study of the comet, scrutinising the surface for a target site for the Philae lander.

Rosetta awakes

January 21, 2014

The European Space Agency is – justifiably – feeling pleased with itself:

Rosetta wake-up signal

It was a fairy-tale ending to a tense chapter in the story of the Rosetta space mission this evening as ESA heard from its distant spacecraft for the first time in 31 months.

Rosetta is chasing down Comet 67P/Churyumov-Gerasimenko, where it will become the first space mission to rendezvous with a comet, the first to attempt a landing on a comet’s surface, and the first to follow a comet as it swings around the Sun.

Since its launch in 2004, Rosetta has made three flybys of Earth and one of Mars to help it on course to its rendezvous with 67P/Churyumov-Gerasimenko, encountering asteroids Steins and Lutetia along the way.

Operating on solar energy alone, Rosetta was placed into a deep space slumber in June 2011 as it cruised out to a distance of nearly 800 million km from the warmth of the Sun, beyond the orbit of Jupiter.

Now, as Rosetta’s orbit has brought it back to within ‘only’ 673 million km from the Sun, there is enough solar energy to power the spacecraft fully again.

Thus today, still about 9 million km from the comet, Rosetta’s pre-programmed internal ‘alarm clock’ woke up the spacecraft. After warming up its key navigation instruments, coming out of a stabilising spin, and aiming its main radio antenna at Earth, Rosetta sent a signal to let mission operators know it had survived the most distant part of its journey.

The signal was received by both NASA’s Goldstone and Canberra ground stations at 18:18 GMT/ 19:18 CET, during the first window of opportunity the spacecraft had to communicate with Earth. It was immediately confirmed in ESA’s space operations centre in Darmstadt and the successful wake-up announced via the @ESA_Rosetta twitter account, which tweeted: “Hello, World!”

Rosetta will be woken up Monday at 1000GMT after a two-and-a-half year sleep

January 19, 2014

The European Space Agency will try and wake-up its sleeping Rosetta spacecraft on Monday at 1000 GMT. The spacecraft entered deep space hibernation in June 2011 when it was too far away from the sun to capture much solar energy. If this works it will be a considerable achievement considering that Rosetta was launched 10 years ago  and the communications technology on board is effectively at least two  “generations” old!

Rosetta trajectory till June 2011

ESA:

At 10:00 GMT on Monday, the most important alarm clock in the Solar System will wake up ESA’s sleeping Rosetta spacecraft.

Rosetta is chasing comet 67P/Churyumov–Gerasimenko and, since its launch in 2004, has made three flybys of Earth and one of Mars to build up enough speed and get on a trajectory towards the comet. It has also encountered asteroids Steins and Lutetia along the way.

Operating on solar energy alone, the spacecraft was placed into a deep space slumber in mid-2011 as it cruised far from the Sun and out towards the orbit of Jupiter. To prepare for its long sleep, Rosetta was oriented so that its solar arrays faced the Sun and put into a once per minute spin for stability.

The only devices left running were its computer and several heaters.

Thirty-one months later, Rosetta’s orbit has brought it back to within ‘only’ 673 million kilometres of the Sun, and there is finally enough solar energy to power the spacecraft fully again. It is time to wake up.

Rosetta’s computer is programmed to carry out a sequence of events to re-establish contact with Earth on 20 January, starting with an ‘alarm clock’ at 10:00 GMT.

Immediately after, the spacecraft’s startrackers will begin to warm up, taking around six hours.

Then its thrusters will fire to stop the slow rotation. A slight adjustment will be made to Rosetta’s orientation to ensure that the solar arrays are still facing directly towards the Sun, before the startrackers are switched on to determine the spacecraft’s attitude.

Once that has been established, Rosetta will turn directly towards Earth, switch on its transmitter and point its high-gain antenna to send its signal to announce that it is awake.

Because of Rosetta’s vast distance – just over 807 million kilometres from Earth – it will take 45 minutes for the signal to reach the ground stations. The first opportunity for receiving a signal on Earth is expected between 17:30 GMT and 18:30 GMT.

Graphic of mission

Rosetta Mission (ESA via BBC)


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