The Space Class lesson "Mission to Mars" is a course in basic physics
and chemistry that utilizes video and flash-based simulations.
The course is grounded in the details of NASA's preferred Mars
mission profile. There are two simulations based lab exercises.

Membrane Lab involves choosing the right semipermeable
membrane to extract carbon dioxide from the Martian atmosphere.

Freeze Lab, concerns harvesting the carbon dioxide by
freezing it in to dry ice and harvesting this mechanically.
The correct strategy is to space out the "freezes" as evenly as possible--
this corresponds to a well-known general principal of efficiency.

Hosted at: http://www.spaceclass.org/
To log in, the name password pair is: guestuser and guestpass

When you log in, you will be at:
http://www.spaceclass.org/controlpanel.aspx

click the "Virtual Lessons" link
Then, at http://www.spaceclass.org/labs.aspx
click the "Mision to Mars" link.
In the Mission to Mars Mission Map page, look at
17. Membrane Lab
and
20. Freeze Lab

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