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nebob2

Banned

Registered: 2002-10-06

Posts: 67

Website

Re: Semi-Direct still primary plan to send men to Mars - Is Semi-Direct plan still being used?

Zero G or not, you also have nearly two straight years exposed to comic radiation. Shielding helps, but exposure racks up outside Earth's protective fields.

AltToWar

Member

Registered: 2002-09-28

Posts: 304

Re: Semi-Direct still primary plan to send men to Mars - Is Semi-Direct plan still being used?

Zero G or not, you also have nearly two straight years exposed to comic radiation. Shielding helps, but exposure racks up outside Earth's protective fields.

The Radiation issue is a bit overrated.  With decient shielding a mars crew will only increase their risk of cancer 10% on a trip to mars.  Thats less then the risk I take while I puff on this cigarette.

Admit it, you just want a big ol' rocket.

---

If you have built castles in the air, your work need not be lost; that is where they should be. Now put the foundations under them. -Henry David Thoreau

nebob2

Banned

Registered: 2002-10-06

Posts: 67

Website

Re: Semi-Direct still primary plan to send men to Mars - Is Semi-Direct plan still being used?

The fact is that most of the spacecraft cannot be decently shielded without rasing its mass dramaticly. Because of this most plans only contain a small 'storm shelter'. And thick shielding can actually make the damage from cosmic rays worse. The majority of the radiation risk is accumulated in transit, on Mars the atmosphere and local materials can be used to produce adaquit shielding. Space is a high radiation environment. I would not be surprised if the Energia plan racks up 150-200 rems for the crew, nearly four times what one would accumulate on a Mars Direct style mission, and 30-40 times the yearly limit in a Govt. facility.

Yes, I do support using technology to shorten trip times without increasing mass signifegently. There is no need for a huge rocket to put a little capsule on Mars.

dicktice

Member

From: Nova Scotia, Canada

Registered: 2002-11-01

Posts: 1,764

Re: Semi-Direct still primary plan to send men to Mars - Is Semi-Direct plan still being used?

How about sleeping "upright" in a 20-foot (say) diameter electric motor driven centrifuge, powered from stationary bicycle generators pumped in tadem by the awake crew?

nebob2

Banned

Registered: 2002-10-06

Posts: 67

Website

Re: Semi-Direct still primary plan to send men to Mars - Is Semi-Direct plan still being used?

It would probibly be easier and more effective to just spin the ship itself rather then work with large, bulky centrafuge systems.

lzrdking

InActive

From: Illinois

Registered: 2002-11-26

Posts: 7

Re: Semi-Direct still primary plan to send men to Mars - Is Semi-Direct plan still being used?

Hey ya if you rotated the entire capsule that help the astronauts then you could create artificial gravity equal to that of Mars so the people could be use to the gravity of Mars before they got there. I think this should be considered when making the hab.

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,433

Re: Semi-Direct still primary plan to send men to Mars - Is Semi-Direct plan still being used?

Fixed shifting and artifacts

like most topics even now its not about the title or first posts in them but drifts like a dune from Thanksgiving wishes to ... you get the picture...

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,433

Re: Semi-Direct still primary plan to send men to Mars - Is Semi-Direct plan still being used?

bump