# "Bouncing-down" on Mars: What's the advantage? **URL:** \ **Category:** Factual Questions\ **Created:** [January 3, 2004, 6:22pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493 "2004-01-03T18:22:34Z")\ **Posts on this page:** 19\ **Page:** 1
**Author:** ![MEBuckner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mebuckner/32/2896_2.png) [@MEBuckner](https://boards.straightdope.com/u/MEBuckner)\ **Post date:** [January 3, 2004, 6:22pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/1 "2004-01-03T18:22:34Z")
Bouncing all over the landscape on giant inflatable rubber balloons (or so I understand the process) seems to be all the rage for Mars landers these days. IIRC the Viking probes back in the '70’s landed using retro-rockets and maybe parachutes, like the Apollo Lunar Modules (obviously sans parachutes in the case of the Apollo program). Is this method of landing probes better in the sense of making it more likely the probe will survive the landing, or is solely it a case of economics: “better, faster, _ **cheaper** _?” ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 3, 2004, 6:24pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/2 "2004-01-03T18:24:31Z")
It’s the latter. Dropping the thing in the general vicinity of where you want it is a lot cheaper than a precision powered landing. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [January 3, 2004, 6:57pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/3 "2004-01-03T18:57:45Z")
Also it means you don’t have to carry any fuel for the landing rockets. ---
**Author:** ![Horatio\_Hellpop](https://avatars.discourse-cdn.com/v4/letter/h/e5b9ba/32.png) [@Horatio\_Hellpop](https://boards.straightdope.com/u/Horatio_Hellpop)\ **Post date:** [January 3, 2004, 8:50pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/4 "2004-01-03T20:50:31Z")
Parachutes don’t work well on Mars. Between the thin atmosphere (which would require a huge 'chute) and the incredibly high winds (which wuld catch that huge 'chute right away), the balloons look very attractive as an alternative. ---
**Author:** ![Doomtrain](https://avatars.discourse-cdn.com/v4/letter/d/0ea827/32.png) [@Doomtrain](https://boards.straightdope.com/u/Doomtrain)\ **Post date:** [January 3, 2004, 9:16pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/5 "2004-01-03T21:16:53Z")
I wonder. Maybe it’s less complicated, too? Put a few balloons and a big ol container of air and you have a fairly simply landing system with less stuff to break than rockets, parachutes, etc. Just speculation. ---
**Author:** ![stuyguy](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@stuyguy](https://boards.straightdope.com/u/stuyguy)\ **Post date:** [January 3, 2004, 9:47pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/6 "2004-01-03T21:47:46Z")
Total, total hijack here… but isn’t the NASA animation of the landing the coolest ever? Not steady, clean and robotic like previous animations. It really looks, well… real! ---
**Author:** ![Nanoda](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Nanoda](https://boards.straightdope.com/u/Nanoda)\ **Post date:** [January 3, 2004, 10:35pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/7 "2004-01-03T22:35:16Z")
It’s just much easier to [land](http://marsrovers.jpl.nasa.gov/mission/tl_entry1.html) this way. You don’t have to worry about strong winds tumbling your craft on touchdown, avoiding [rocks](http://www.cnn.com/TECH/9706/pathfinder/mission/technology/) that tip it over, stuff like that. The only downside I’ve ever seen about it is that after you land, the bags might get in the way. I saw an episode on Discovery about the animation… IIRC, it’s the work of mostly one guy, who actually went to see how the things got built, so his representations of it would be that much more accurate. (Things don’t deploy perfectly smoothly, everything isn’t stiff, etc). He made a fairly long, detailed movie, not just the short [clips](http://marsrovers.jpl.nasa.gov/gallery/video/animation.html) [NASA](http://marsrovers.jpl.nasa.gov/home/index.html) has up. I think [these](http://dsc.discovery.com/news/features/mars/media/marsvideo.html) might be from it too, I dunno. Aha! [Here’s the guy](http://www.maasdigital.com/mervideo-tech.html). Dan Maas. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [January 3, 2004, 10:54pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/8 "2004-01-03T22:54:22Z")
Also until recently it had a 100% percent success rate ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [January 4, 2004, 4:32am UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/9 "2004-01-04T04:32:10Z")
Here’s a quick little cheat on downloading that movie. The Quicktime download is a 18MB low res version. The only other one is a huge 320MB DVD quality one (and also requires a download client to be installed). A nice compromise is to save the LARGE Fast Broadband playable one. After it starts playing, pause it, and wait for the black bar, which moves ahead of the playtime arrow, to reach the end. Then copy the 64MB .mov file from your Temporary Internet Files folder. ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [January 4, 2004, 5:31pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/10 "2004-01-04T17:31:16Z")
Seems to me it would reduce peak G’s on landing, by allowing deceleration of the spacecraft over a larger distance (the compression of the balloons) than with a parachute-type impact. That allows some combination of improved likelihood of survival, and designing the spacecraft smaller / putting more stuff in. ---
**Author:** ![Bryan\_Ekers](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bryan_ekers/32/183_2.png) [@Bryan\_Ekers](https://boards.straightdope.com/u/Bryan_Ekers)\ **Post date:** [January 4, 2004, 5:38pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/11 "2004-01-04T17:38:05Z")
I just hope there aren’t any children or short people aboard. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [January 4, 2004, 5:53pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/12 "2004-01-04T17:53:27Z")
> [@](#): > > \*Originally posted by stuyguy \* > \*\*but isn’t the NASA animation of the landing the coolest ever? Not steady, clean and robotic like previous animations. It really looks, well… real! \*\* I’m sure they can afford the latest in CGI technology. IIRC, NASA projects are required to spend at least 1% of the budget for public outreach. ---
**Author:** ![Diceman](https://avatars.discourse-cdn.com/v4/letter/d/22d042/32.png) [@Diceman](https://boards.straightdope.com/u/Diceman)\ **Post date:** [January 4, 2004, 8:57pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/13 "2004-01-04T20:57:16Z")
I can’t help but imagine the lander coming to rest on the surface of Mars, and then a giant hand emerges from the top and begins popping the bubble wrap to free the robot inside. ---
**Author:** ![user\_hostile](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/user_hostile/32/474_2.png) [@user\_hostile](https://boards.straightdope.com/u/user_hostile)\ **Post date:** [January 5, 2004, 12:00am UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/14 "2004-01-05T00:00:41Z")
Nah, they use a Daisy Red-Eye B-B Gun with a compass in the stock (space-rated of course). ---
**Author:** ![NoGoodNamesLeft](https://avatars.discourse-cdn.com/v4/letter/n/8797f3/32.png) [@NoGoodNamesLeft](https://boards.straightdope.com/u/NoGoodNamesLeft)\ **Post date:** [January 5, 2004, 2:21pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/15 "2004-01-05T14:21:17Z")
…and this thing that tells time? ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [January 5, 2004, 2:56pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/16 "2004-01-05T14:56:06Z")
> [@](#): > > \*Originally posted by Hail Ants \* > \*\*Here’s a quick little cheat on downloading that movie. The Quicktime download is a 18MB low res version. The only other one is a huge 320MB DVD quality one (and also requires a download client to be installed). > > A nice compromise is to save the LARGE Fast Broadband playable one. After it starts playing, pause it, and wait for the black bar, which moves ahead of the playtime arrow, to reach the end. Then copy the 64MB .mov file from your Temporary Internet Files folder. \*\* I couldn’t find a link to the 320MB (or even the broadband playable) version; am missing something? ---
**Author:** ![Nanoda](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Nanoda](https://boards.straightdope.com/u/Nanoda)\ **Post date:** [January 7, 2004, 8:01am UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/17 "2004-01-07T08:01:12Z")
Yes, you are. And you’ll need BitTorrent to Dl it. The link page is [here](http://www.maasdigital.com/bittorrent/index.html). ---
**Author:** ![Moe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moe/32/2972_2.png) [@Moe](https://boards.straightdope.com/u/Moe)\ **Post date:** [January 7, 2004, 4:53pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/18 "2004-01-07T16:53:35Z")
From **Nanoda’s** [link](http://marsrovers.jpl.nasa.gov/mission/tl_entry1.html) > [@](#): > > In only six minutes, the spacecraft will slow down from 12,000 to 0 miles per hour HOLY FLURKIN’ SHNITT!! Did a C&P that correctly? Twelve thousand miles an hour?? [Keanau Reeves] Whoa! [/KR] ---
**Author:** ![robo99](https://avatars.discourse-cdn.com/v4/letter/r/a8b319/32.png) [@robo99](https://boards.straightdope.com/u/robo99)\ **Post date:** [January 7, 2004, 5:11pm UTC](https://boards.straightdope.com/t/bouncing-down-on-mars-whats-the-advantage/222493/19 "2004-01-07T17:11:25Z")
They can send a craft to Mars but they can’t allow downloads due to low bandwidth:) They had a 1 hour documentary on Spirt on PBS last night. The most up to date doc I’ve ever seen - it had scenes from three days ago. I didn’t realise that there’s another identical rover landing in a month on the other side of the planet.