It seems like the current fad to get things down to the red planet is to use a parachute, some week retrorockets to slow the thing down a bit, and maybe prevent tumbleing, and land on a bunch of bags, and roll to a stop.
Could this method be used to ‘reasonably’ get humans onto the surface? Meaning with a high probability of not hurting them too much (or killing them) and having them land in an area where they would be able to make it to other things we landed there such as shelter, food, water, air and a return rocket?
Given big enough parachutes, maybe they could, but it wouldn’t be a pleasant landing. After several months of zero-G en route from Earth to Mars, the craft would experience substantial deceleration forces once it entered the atmosphere. In the cases of the Mars Exploration Rovers, they decelerated from 12,000 mph to nearly zero in six minutes, which I used Google calculator to translate to an average of about 1.5g. That wouldn’t be so bad, I suppose, but once the parachute was released just above the surface, the several minutes of tumbling and bouncing that followed would be unkind to the body of an astronaut acclimated to months of weightlessness.
Electronics, like in the rovers, can be made a lot more durable than a human body, for example by potting everything in epoxy. Consider that the previous failed Mars mission included probes that would actually be embedded in the ground by impacting the surface. Bones and internal organs can’t withstand nearly the magnitudes of sustained or sudden acceleration that electronics can be made to.
It’s funny you mention that. I hadn’t been following the story and hadn’t seen the NOVA special on the landing. My husband was relating it all to me, and when he started to describe the big bouncy airbags, I waved him off and said “Oh, yeah, sure, I saw that in a movie.”
If I recall correctly, Spirit’s first bounce on the surface of Mars produced an deceleration of ~40 gravities. That would hurt living passengers. A lot.
Actually, the rover was designed to survive a 40g impact. But in the case of Opportunity, the initial data indicated an impact of only 2 - 3 g’s. Easily survivable for a human. They may get a bit woozy if they traveled to Mars in zero-g, but if they had artificial gravity during the trip the landing would be a piece of cake.
wiseass hijack Oh sure, artificial gravity. Yea we can just smack some special tiles down and have that on any of our ships. Takes about 5 hours to do and we even have a loaner spaceship so you can get to work or run errands while you wait for your new artificial gravity system. Hehe /wiseass hijack
No offense meant to RSA, but I think it would be a bit easier to lessen the impact, develop a physical training regemein to prepare the astronauts, or some special seating to make it easier on them than develop artificial gravity.
Is there any data on the Moon landing? It was done after a shorter period in space and had less gravity than Mars, but there should be some info to be gleaned from that that might help this discussion.
There are several workable methods for achieving “artificial” gravity that don’t involve developing some gravitationally-attractive floorboards. One is a cyllindrical or torus ship that spins on its axis. Another is a ship that constantly accelerates at some fraction of 1g.
While a ship that spins on its axis would be quite workable with current building techniques (thought it would probably add considerable weight, another problem in itself), a ship that constantly accelerates at any appreciable fraction of a g is not happening anytime soon, unless NASA has some new propulsion technology that they haven’t told anyone about.
But it would be really cool if they could - it would cut travel time down to darn near nothing.
