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Old August 13th 13, 06:28 PM posted to sci.space.moderated
Brad Guth[_3_]
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Default When is manned spaceflight preferred?

On Friday, June 7, 2013 1:03:05 PM UTC-7, Martha Adams wrote:
On 5/7/2008 2:03 PM, BradGuth wrote:

On Apr 7, 6:41 am, "Jeff Findley" wrote:


"Herman Rubin" wrote in message




...




Robots cannot even do a good job of surveying Mars.


Robots cannot think, and if one needs a half hour round


time to communicate, it is necessary to be very careful


near the edge of a cliff or a slope. So robots moving


at one mile per day explore little.




The two Mars rovers are often touted as a pair of cheap, unmanned, missions


able to cover more terrain than a lander. While true, they do move very


slowly. Over the years, they have covered distances that are still very


small when compared to what the Apollo astronauts did in the (obviously


manned) lunar rover.




It's also interesting to note that with a man on the spot, equipment like


the lunar rover can be made a lot "dumber" than an unmanned piece of


equipment. The man in the suit can be the control system, communications


system, and even the maintenance system for the equipment. I believe I


recall one of the rovers getting an improvised fender, installed by an


astronaut on the spot. That's more than a bit difficult to do remotely.




Here's a reference (I love Google):




http://www.lpi.usra.edu/lunar/missio...7/surface_opp/




The above shows a nice "traverse map" showing how far the Apollo 17


astronauts were able to travel with the lunar rover as well as a close up


picture showing the "repaired" fender.




The other thing to note about manned missions is that you typically plan on


bringing the astronauts back at the end of the mission, so adding "sample


return" to the mission is far easier than trying to design it into an


unmanned mission. An unmanned sample return mission would be a very good


mission to fly to Mars, but this mission always seems to be just beyond the


limits (technical and cost) of what an unmanned mission can do using today's


launch vehicles.




Jeff


--


A clever person solves a problem.


A wise person avoids it. -- Einstein




.




Most any terrestrial science technology can be safely deployed upon


the likes of Mars. However, of far better worth than even peeing on a


hot rock, is to send a robotic rigid airship to cruise efficiently


around Venus, well below them acidic clouds.




You folks do realize it's not nearly as humanly or rather ET


insurmountable as we've been told, and most certainly not


technologically insurmountable for robotics. Would you like to see


for yourselves?


. - Brad Guth




================================================== =======



How about *above* the acid clouds? Seems to me, Venus might be a good

place for a city buoyant like a blimp, floating above the clouds. I

don't know the atmosphere pressure gradient there, but from sf writing

I've seen, I've an impression a near-Terra atmosphere pressure exists

there above the clouds, making the floating city feasible. Like in Star

Wars.



A large conical reflector, and a lot of tech, would make a sub-Mercury

orbital station possible. Might be named Vulcan, of course.



Titeotwawki -- Martha Adams [Sun 2013 Jun 02]


There's not much to do above 65 km, and for the most part you'd be freezing to death at least half of the time, and seriously damn cold the other half of the time. Solar and cosmic radiation of the bad kind would also be an issue.

A composite rigid airship could operate safely and efficiently well below those acidic clouds (say 15 km), landing as often as needed. A shuttle craft gets you to/from Venus L2.

Why not utilize the best available technology in order to exploit a nearby planet like Venus?