back to article Let's go to Mars, dude: Euro space parachute passes maiden test

The European Space Agency (ESA) claimed today that the first test of the giant parachute destined for use by the ExoMars lander has been a success, paving the way for more ambitious trials before an eventual attempt on the Red Planet itself. The 195kg parachute assembly was lofted to 1.2km above Kiruna, Sweden, before being …

not a fluid dynamics expert but...

... given that the atmospheric density, the strength of gravity and velocity at opening are all markedly different between here and Mars, how relevant is a test carried out here at a relatively low altitude?

Or is this something where you test the design (i.e. shape, unfurling mechanism, etc.) but then use a model and some maths to make it a different size/aspect ratio/whatever for the Mars version?

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Re: not a fluid dynamics expert but...

If you go high enough up conditions are similar enough to test the systems. Well, as good as you can get without having a spare planet in the shed!

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Boffin

Re: not a fluid dynamics expert but...

I thought Mars WAS our "spare planet in the shed"!

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Re: not a fluid dynamics expert either but...

As I understand the article, the main objective of this test was to validate the pilot chute / main chute sequence. Another test in more Mars-like conditions (from 30 km altitude) is planned next.

They have also probably collected useful data from the telemetry during the descent.

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Re: not a fluid dynamics expert but...

> "If you go high enough up conditions are similar enough to test the systems."

The tripled gravity might actually be good, so as to moderately over-stress the chute components and test their mechanical integrity.

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Re: not a fluid dynamics expert but...

I am neither a fluid dynamics expert, and I wonder does gravity matter that much? The point of this thing is to slow it down at entry*, right? And it feels like there is basically three things that should affect how a parachute performs, velocity, air density and the force the payload drags it along with. Shouldn't the momentum of the thing at deployment be the main contributor of said force, and not gravity that maintains it when it has slowed down to terminal velocity?

*sounds wrong, but it can't be reentry.

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Re: not a fluid dynamics expert either but...

More useful than the data from 1969?

What was it, 11 mission splashdowns within 1 mile of the target, including the random button pushing AS13?

Funny how Project Orion, now in it's 18th year hasn't got a clue about either heat shields or parachutes either. Still, at least they admit how dangerous Van Allen belts are - they even switched off their CM cabin camera to 'protect it' for that bit of their one and only (manless) mission.

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Re: not a fluid dynamics expert but...

> "...I wonder does gravity matter that much?"

Gravity determines terminal velocity at a given pressure and cross-section. Basically the chute will be dragged thru the air more forcefully.

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Boffin

Re: not a fluid dynamics expert but...

Austin Meyer, the author of the flight simulator X-Plane set it up to simulate flights on mars:

http://www.x-plane.com/adventures/mars.html

The synopsis is that it is hard. Inertia problems are compounded by low gravity and thin air. It requires massive amounts of energy to take off and arresting gear to stop.

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From the linked article.

The Schiaparelli probe was an experiment to test the landing process on Mars.

So smirking about a test that exposed flaws in the landing process seems a little hubristic. Yes, it was an expensive test but it was still a test.

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Not quite 100% landing failure

The Beagle 2 vanished. The ESA postmortem report damned the project, especially the smaller parachute and crashbags approach to landing.

Many years later, it would appear that the Beagle 2 landed intact, but for whatever reason the solar panels didn't properly deploy. So yes, that landed fine.

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Re: Not quite 100% landing failure

It can look ok from orbit but suffered higher than planned deceleration due to "landing failure" that would cause the solar panal deployment to subsequently fail as well. I would not rule out "100%".

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Anonymous Coward

I wouldn't parachute to mars, there is no atmosphere so how would you throw a decent party?

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Coat

Surely you'd throw a descent party?

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Anonymous Coward

or a mars party. (NSFW)

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Anonymous Coward

If I could..

If I could go to Mars I would.

Heck if I could go anywhere in Space I would! Always been one of those things that has been a childhood dream, explore the universe.

But alas, I'm but a poor pirate who is bound to the sea.

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Re: If I could..

What Elon Musk never mentions about either the moon or mars is the constant hard radiation.

It makes the very ground and dust radioactive, aluminium moderates it to become X-rays and neutron showers and you can't escape because even away from the sun you have galactic and cosmic ray particles.

All caused by the lack of a proper magnetic field, which also allows the atmosphere to be blown away into space by the solar wind, only the odd weak magnetic loop allows some to linger for a while.

The 'answer' is to live in deep caves, rather easier to do on earth, so mars is impossible and totally pointless to visit. The R&D makes an excellent cover for developing rocket powered missiles for war though.

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Re: If I could..

I tried to do the math on how much uranium we would need to heat up the core to get it going again. We are talking back of the envelope calculations here, but around 300 billion tons of uranium 235. If we go for an matter-antimatter reaction we could get away with 5 million tons.

Pitch it to Elon and I bet he'll say that it can be done by 2023 or something.

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FAIL

Wtf

The Usasians have landed 3 probes successfully on Mars recently - why is the ESA pissing money up the wall with new landing systems when they can just get a working one from the Yanks?

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Stop

Re: Wtf

You are Lewis Page, and I claim my £5.

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Coffee/keyboard

Re: Wtf

I think I peed my pants a little bit.

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Re: Wtf

Why acquire a working one from the Usaians when we, Europe, can just tune into your data streams?

Copyright be damned. Does it even apply in space?

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Terminator

Re: "Copyright be damned. Does it even apply in space?"

In space, no one can hear you sue.

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Re: Wtf

@Gordon10

Because the EU needs to make its annual pork production quota?

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DJO
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Re: Wtf

get a working one from the Yanks?

So once the Yanks had one that worked why did they come up with 2 different solutions for the next 2 missions?

Every payload needs a slightly different solution, what worked for one lander wont necessarily work for any other payload so there's little advantage to be gained.

This stuff is quite complicated*, there's no "off the shelf" solutions when everything is essentially experimental.

I'm certain ESA already have full access to all the design and telemetry from the previous NASA missions and use whatever information is relevant.

* "rocket science"

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Mars Curiosity is exploring Devon Island off Freeland....BeforeItsNews website

NASA forgot to have NSA front company GooGhoul turn off their Earth image maps....

photos show NASA film crews, satellite uplink....just add red filter to images....

"Perplexing Apollo Questions for NASA" at FauxScienceSlayer.com

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Re: Wtf

That’s pretty much my point - they should stop blinking doing it. This is basically a cutting edge cottage industry. If we ever want to do space right we need to take a leaf out of Henry T Fords book and modularise and standardise. Yes the initial expense is much higher but look what happens when you do -you end up with something like SpaceX which has reduced the cost to orbit of a payload by a stupid amount.

It’s short sighted and stupid. (And regrettably human nature)

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Perplexing sanity questions for Faux Science Slayer

Why haven't you ever figured out how to create a hyperlink like this https://forums.theregister.co.uk/forum/1/2018/03/15/kepler_space_telescope_mission_ending_soon/#c_3456623?

Why do you keep pasting the same nonsense into article after article with only the most tangental connection to the subject?

Are you ever discouraged by how many downvotes your witterings receive? Or do you view it as a badge of honour "they laughed at Galileo..." etc?

Do you ever read the comments following yours, or just flap on to drop some guano in the next thread?

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Anonymous Coward

Re: Wtf

I think that they're trying to convince the Yanks to launch the B-Ark first

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Russian rocket?

"ExoMars 2020, which compromises an orbiter and a rover, is slated to launch on a Russian Proton rocket"

Hmmmm....so ESA have a current 100% lander failure rate. The Russians don't have a stellar record on Martian excursions either. Fingers and toes crossed for this one!

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"ExoMars 2020, which compromises an orbiter and a rover..."

"ExoMars 2020, which compromises an orbiter and a rover, is slated to launch on a Russian Proton rocket in 2020, with the rover due to arrive on the surface in March 2021."

It's unlikely to arrive any time if it's compromised. Maybe he means "consists of"?

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Re: "ExoMars 2020, which compromises an orbiter and a rover..."

"It's unlikely to arrive any time if it's compromised. Maybe he means "consists of"?"

More likely to be "comprises"... :-)

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Boffin

Note that space'x engine restart at c30Km let NASA cut their "supersonic retro propulsion"

project budget from about $80m to about $10m.

But yes low ground behavior is going to be tricky to simulate as Mars surface atmospheric pressure is 1/160 of that of Earth.

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Are we still supposed to believe in Apollo?

1969 and there were men jumping about playing golf on the moon, nearly 50 years later and we've managed to parachute something down?

How come nether the US or EU know how to get a man into space today?

The US are still struggling to build a rocket, yet we're supposed to buy the Apollo fairy story of a Dan Dare expedition?

Each tiny step the US/EU makes toward orbit (let alone space) reminds us how much of Apollo was total fiction and fuzzy TV studio output.

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Amusingly it turns out that with the technology of the time, it would have been harder to fake the footage than it was to actually go to the moon.

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You know we've done a lot of really cool stuff in space since Apollo, right? The scientific value of manned moon missions (or indeed Mars) are now quite low and added to the current political climate of angry tweets instead of nation state willy waving, the more or less pointless manned missions have taken a back seat.

But whatever, conspiracy this and that lol

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