MARS - How do parachutes even work?

Hello!

As any good conspiracy theorist I find myself going onto YouTube looking for a recipe for salad dressing ... and end up looking at MARS LANDING IS A HOAX videos for three hours - then preparing my tin-foil hat. Joking aside, one thing I am genuinely curious about is how we could land rovers on Mars utilizing parachutes. Something I can't find addressed or asked. How do parachutes work on Mars?

Mars has 38% the gravity of Earth, according to these guys: here.

Mars has 100 times less atmosphere as Earth according to the same guys: here.

According to the US Air Force parachutes work like this:



Gravity and Air Resistance. Increase the Air Resistance, and you create enough drag to slow yourself down. Now while Mars only has 38% of the gravity it has 100 times less air resistance. How in the world would a parachute even work? Yet they used parachutes in the rover landings sans the one they used a cable crane / boosters. As seen here!

I am genuinely curious. How do parachutes even work on Mars?

a reply to: KaDeCo

By using a larger parachute, you get the same effect. The parachute used in 2003 was 40% larger than previous chutes. They're testing a parachute off Kauai that's 110 feet in diameter, designed to land people on Mars safely.

a reply to: KaDeCo

Maybe instead of watching 3 hours of Mars hoax videos, it could have been better spent reading up on what you asked..

Here's a start:

www.ssdl.gatech.edu...

They work the same way as they do on earth just less efficiency. The probe just needed to be slowed down from 9xx mph to 2xxmph and then the boosters slowed it down the rest of the way.

a reply to: KaDeCo

Good point. Doesn't add up.

Not sure whether it works this way, but compared to Earth, a parachute would only be roughly 3% as effective on Mars?

So to get the same life-saving effect it would have to be ??? 30x bigger?

I'm sure it's not quite that extreme, but even a 100' chute doesn't seem anywhere near big enough.

a reply to: Urantia1111

Which would be why a chute isn't the only slowing device used when landing on Mars.

a reply to: Zaphod58

Would it? What are the others?

What makes up for the other 97% of life-saving deceleration?

a reply to: Urantia1111

NASA has used rockets and airbags to land probes. The rocket fires a certain distance off the ground to slow it more, and the airbags deploy around the entire probe and cushion the impact. The parachute is the initial slowing device.

a reply to: Urantia1111

The Phoenix lander used friction, then a chute, then finally boosters to land.

It only doesn't add up to those who aren't interested in the science behind landing a craft on Mars.

a reply to: KaDeCo

I think they only slowed it down with shutes.

And "landing it" would'nt be the way I would describe deploying airbags and crashing it down onto the surface. Which would be how I would describe it.



I am not surprised that it still works after this many years if it was designed to "land" like that. Lol.

a reply to: Chadwickus

I am interested, hence the inquiry.

So live astronauts are going to go bouncing along the surface of Mars on airbags and they'll be ok with that?

Won't that be particularly damaging to their bodies weakened by months in space?

a reply to: Urantia1111

No, they only use that for unmanned probes. As I said, they're testing a 110 foot supersonic parachute off Kauai. That's bigger than parachutes used in the past, which will make it more effective. That combined with rockets, and whatever other technologies they develop will enable a softer landing.

originally posted by: Zaphod58
a reply to: Urantia1111

NASA has used rockets and airbags to land probes. The rocket fires a certain distance off the ground to slow it more, and the airbags deploy around the entire probe and cushion the impact. The parachute is the initial slowing device.

NASA even had a complete explanation of how this was all to be achieved.

Everything is a hoax hey.. lol

Can't imagine why on earth - no pun intended - this would even have to be a hoax.

a reply to: Urantia1111

I never mentioned airbags.

Boosters are used for the final touch down for a soft landing.

And will most likely be the method (including a parachute) for landing people on Mars

I completely understand the use of boosters and other ways to decelerate, that they considered air-bags to land and then used the crane / booster combo, but parachutes won't even deploy at 100 times less atmosphere. I guess I can understand if they have some sort of deploying device that is added to the payload on descent that then 'puffs up' the parachute, but that still does not explain how any significant drag is created.

In the documentation supplied above where the rude guy said I should read up on the statistics instead of watching videos about rocks that weren't skulls - of how they calculated they -would- in the future use sensors in descent to eliminate the uncertain variables of the radical atmosphere on Mars. It more discusses the appropriate heat shield (used to slow), and trajectory (providing as much atmosphere between object and landing) as the atmospheric anomalies in previous recordings had +/- 40% variable velocity. due to the thin atmosphere than the composition of the atmosphere itself.

But the same problem is presented: how do the parachutes work?

When I did look it up, I was thinking that the moderator was probably right a bigger chute could work - and without as much initial drag the problem of deploying the parachute higher (and then catching on fire plummeting billions of dollars into Martian sand) would be resolved, but that would have to be one big parachute. Kim Aarons, aerospace engineer stated on parachute and entry to atmosphere:

The parachutes that we currently use are designed to slow down the entry vehicle only after they have already lost most of their kinetic energy using a heat shield. However, it you were to design an incredibly large incredibly lightweight parachute and figure out a way to open it up in space before you entered the atmosphere, then it just might be possible to use it to do the job of slowing you down from orbital speed and eliminate the heat shield. The deceleration would occur much higher in the atmosphere where the air is even closer to a vacuum that where current heat shields operate. It turns out that due to the exponential decrease in density with altitude, the decelerate would be essentially the same for any ballistic coefficient. So this hypothetical parachute would still experience about 10 g's of deceleration. But because it would happen in lower density air, the dynamic pressure would be lower and so would the heating rate (W/cm^2). The problem is make this incredibly large and incredibly thin parachute take the deceleration loads.

It still is difficult for me to wrap my mind around.

a reply to: Zaphod58

Hmm. "Supersonic" eh? Maybe.

Still sounds a little sketchy.

I guess that's to be expected from a space program still in its infancy.

Well, I sincerely hope they make it down safely.

originally posted by: Chadwickus
a reply to: Urantia1111

I never mentioned airbags.

Boosters are used for the final touch down for a soft landing.

And will most likely be the method (including a parachute) for landing people on Mars

And I wasn't even really asking anything of you.

You chimed in, as usual, just to be a jagoff.

Anyway, Zaphod says there's going to be airbags and supersonic parachutes so you may wish to check with him on this.

Alright I found an answer that makes sense to me:

A chute that could lower our lander to the Martian ground at a gentle 10 m/s (22 mph) would have to have an area about 42 times larger than our "little" chute (or a diameter of 263 ft)! That's 42 times the mass (and volume) of our 10 kg chute, or 420 kg, more than the mass of our entire lander! It wouldn't fit! We would need to have a "gossamer" (ultra-light weight material) parachute and then figure out how to get it open at high speeds. So, the short answer is, parachutes don't work on Mars like they do on Earth (neither do airbags, but that is another story), but they do a great job when you need to slow down something that is whipping through the Martian atmosphere FAST!

a reply to: Zaphod58

Parachute plus rockets... 😊

Edit.. re-watch the videos.... and rockets are mentioned.😠

a reply to: Urantia1111

No, I said they used airbags. They haven't said how they're going to land people on Mars yet, besides an extremely large parachute to help slow them down.