Updates ExoMars News & Updates

[Nicholas Kang]

The director seems annoyed?

---------- Post added at 04:22 PM ---------- Previous post was at 04:20 PM ----------

He is absent now.

---------- Post added at 04:23 PM ---------- Previous post was at 04:22 PM ----------

2020 mission already funded, not affected.

---------- Post added at 04:24 PM ---------- Previous post was at 04:23 PM ----------

About 50s time gap between lost of signal and expected landing time.

---------- Post added at 04:26 PM ---------- Previous post was at 04:24 PM ----------

Speed nominal until post-parachute phase.

---------- Post added at 04:28 PM ---------- Previous post was at 04:26 PM ----------

Parachute phase may have terminated too early.

Lander might be far too low.

Again, not enough data to conclude.

 

[RGClark]

European Spacecraft May Be Lost on Mars.
The Schiaparelli lander’s failure to phone home has scientists fearing the worst.
By Lee Billings on October 19, 2016
https://www.scientificamerican.com/article/european-spacecraft-may-be-lost-on-mars/

The signal was lost during the retrorocket firing part of the descent. So what could have gone wrong? It could have simply been a case of loss of attitude control where it couldn't maintain signal lock.

Bob Clark

 

[Nicholas Kang]

David is concluding the conference now!

Exploration is hard, that is one of the reasons we do it!

Conference ended!

 

[Urwumpe]

I wonder if the navigation system had a failure. Some words from the press conference sound like EDM data and MEX doppler data diverge.

 

[Notebook]

http://www.esa.int/Our_Activities/Space_Science/ExoMars/Schiaparelli_descent_data_decoding_underway

20 October 2016
Essential data from the ExoMars Schiaparelli lander sent to its mothership Trace Gas Orbiter during the module’s descent to the Red Planet’s surface yesterday has been downlinked to Earth and is currently being analysed by experts.

“In terms of the Schiaparelli test module, we have data coming back that allow us to fully understand the steps that did occur, and why the soft landing did not occur,” said David Parker, ESA’s Director of Human Spaceflight and Robotic Exploration.
 “From the engineering standpoint, it’s what we want from a test, and we have extremely valuable data to work with. We will have an enquiry board to dig deeper into the data and we cannot speculate further at this time.” 

 

[Notebook]

http://www.bbc.co.uk/news/science-environment-37715202

Schiaparelli Mars probe's parachute 'jettisoned too early'

 

[fred18]

"Why the soft landing did not occur" so no more hopes of communication issues, we can say that Schiaparelli has crashed then...

 

[Ravenous]

Also from that BBC page:

In the downlinked telemetry, Schiaparelli is seen to continue transmitting a radio signal for 19 seconds after the apparent thruster shutoff.

19 seconds free fall under Mars gravity (plus whatever the initial downward velocity was) - oh well, it was only a test after all

On the bright side the orbiter always was the important thing. So still worth a beer.

 

[Fabri91]

It's the Soviet-Russian Mars Curse striking again.

 

[Ravenous]

By the way the lander apparently had a very small retroreflector on it. Wonder if that survived and is usable. (Though I'm not sure there's anything in orbit that can do laser ranging on it at the moment.)

 

[Urwumpe]

So, it dropped at least 670 meters and impacted at at least 70 m/s (assuming zero downward velocity).

 

[GLS]

So, it dropped at least 670 meters and impacted at at least 70 m/s (assuming zero downward velocity).

That's gotta hurt, I don't care which planet you're landing in.

 

[Enjo]

So it seems that the whole procedure was preprogrammed like a pitch program, not as a closed loop system - ie. the parachute deploying earlier didn't mean that it would be held for longer to bleed off energy, but for the same amount of time as if it was deployed on time...
Am I missing something or was it a typical case of hard-coding?

 

[GLS]

So it seems that the whole procedure was preprogrammed like a pitch program, not as a closed loop system - ie. the parachute deploying earlier didn't mean that it would be held for longer to bleed off energy, but for the same amount of time as if it was deployed on time...
Am I missing something or was it a typical case of hard-coding?

I think a radar failure/obstruction could also account for what happened.

 

[Ravenous]

We could probably think of a hundred possible failure causes. (And the actual cause will turn out to be number 101.)

Let them work out the data themselves.

By the way - I did search around for technical info on the lander some time ago, and found very little. Typically for NASA/JPL spacecraft you can find some published information with a lot of searching, but for a typical ESA project it seems to be harder to find. (I'm thinking of decent drawings, some technical information etc.) Not sure if there's a reason for this, or if things are regarded as more "proprietary" at ESA. (Just an observation, I'm not making a complaint.)

 

[Urwumpe]

We could probably think of a hundred possible failure causes. (And the actual cause will turn out to be number 101.)

Let them work out the data themselves.

By the way - I did search around for technical info on the lander some time ago, and found very little. Typically for NASA/JPL spacecraft you can find some published information with a lot of searching, but for a typical ESA project it seems to be harder to find. (I'm thinking of decent drawings, some technical information etc.) Not sure if there's a reason for this, or if things are regarded as more "proprietary" at ESA. (Just an observation, I'm not making a complaint.)

Its typical for ESA. You need to dig a lot more, because contrary to NASA, the work of ESA is not automatically considered public domain, but copyright protected. Same applies to data - if you want to get satellite data from the USA, you just need to ask for it, they always have some sort of basic access for free and for all. For ESA, its very uncommon that you can get even just this basic access without a university as sponsor.

Its pretty annoying at times, because WE paid for it.

 

[Notebook]

Friend of mine asked "Why don't they do the rocket firing(Mars Orbit Insertion) on the side of Mars facing Earth". I could probably confuse him and myself, anyone point me in a good explanation of why not?

Thanks, N.

 

[Enjo]

Friend of mine asked "Why don't they do the rocket firing(Mars Orbit Insertion) on the side of Mars facing Earth". I could probably confuse him and myself, anyone point me in a good explanation of why not?

Thanks, N.

Because this would put the orbiter into a retrograde orbit - rarely needed.
Why retrograde? Because most planets (except Venus) rotate in the same direction as their orbital motion around Sun. So you can imagine such a rotating planet in the same direction, and to orbit it in the same direction, you have to approach it "from behind".

 

[Urwumpe]

Friend of mine asked "Why don't they do the rocket firing(Mars Orbit Insertion) on the side of Mars facing Earth". I could probably confuse him and myself, anyone point me in a good explanation of why not?

Thanks, N.

In brief: Because it requires less fuel.

You could of course place the point of the closest Mars approach on the side facing Earth. But for that, you would need to encounter Mars in a pretty strange way, overshooting Mars first by a long distance, let it overtake you while you are some distance further away. And then you encounter it with a much higher velocity difference, that you need to reduce.

 

[Notebook]

Thanks both, that should be enough for him to be getting on with!

N.