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The link in the post above has an error.  It wasn't hard to find the working link, though.

The pictures in question appear to be those of the bright soil patch that the spirit rover found itself stuck in shortly after its recent wheel failure in late March.  IMHO, they indicate the very recent presence of liquid water.  The deposits are located under a very shallow layer of surface dust.  While the deposition of wind blown dust is relatively slow on Mars, it did not take three billion years to lay down a mere centimeter of dust.  It did not even require a thousand years.   

Unfortunately, contrary to what the article may say, those pictures are probably neither mud nor ice. 

The material is clearly not a frozen block of anything - Spirit got stuck in it.

The material also does not exhibit the sort of adhesion, clumping, or sagging that one would associate with mud or even unusually moist soil.  Whatever it is, there isn't enough liquid water left in it to make the grains stick together.  Other photos from that incident show that it was churned up by the working wheels, with patches of the bright material thrown up on top of the surface soil or piled on other layers in a thoroughly powdery fashion. 

But, it seems to be mostly salt, probably water soluble salts, and all that salt had to get there somehow within the last thousand years.  It did not blow in on the wind. 

The only obvious way to create that deposit is inundation with liquid brine.  Evaporation of the water content would leave a powdery layer of freeze-dried dust and salt, and I believe that is what Spirit found. 

Dust and salt are everywhere on Mars - we can't even keep them off of the rover. But water formed deposits that are this geologically young may be rare.  This deposit is less than a thousand years old, it is accessible, and Spirit will be sitting just a few meters from it for the next few months.  It is entirely possible that there may still be liquid brine only a meter or so beneath the surface at that point.  If the process that laid down that salt is still ongoing, Spirit's confinement at Low Haven may enable it to observe traces of it in action. 

I'd prefer a front end loader, but the mini thermal emission spectrometer might be sufficient given a few months of continuous observations.

I don't think a simple airfoil of just any type picked out of a hat is going to get this type of vehicle to orbit. 

The point of minimum vertical force is always waiting for anything trying to employ aerodynamic lift.  Having a net weight - not floating at equilibrium - only subtracts weight from the available vertical force, causing the minimum to come that much sooner. 

If a vehicle dependent on aerodynamic lift to maintain altitude cannot get its net weight under that minimum vertical force, it can never ascend to orbit.

Unfortunately, wings large enough to do the job are large.  Heavy too.  A simple parasail won't work because there has to be sufficient aerodynamic lift to keep it open at all times, and eventually there won't be.  Stiff wing support with compressive strength is required.  Gas filled wings would fill the bill, but wings large enough to be useful for this scheme would take several minutes to fill, and wouldn't be something you could just pop out of your rocket.  Serious vertical velocity, on the order of at least 3 km/s, would be required for the flight time to even deploy them - there'd be no talk of a checklist.

Having a high altitude rocket plane to maintain it at altitude only gets around these problems until the vehicle is cut loose and has to worry about its own drag.

It would be more practical to just add a rocket stage on the top of that booster instead of a winged vehicle.  And, BTW, if you're going to use a gas-filled anything, why not just make it a bouyant airship?

(Yes, GCNR, I'm aware that I'm becoming a vaporware apologist.  "Take up your Airship-To-Orbit and follow me", etc., etc.)

No, I don't think this could get you to orbit.

Kevin Murray's space.com article, The Accidental Space Activist, has a few good ideas for educational outreach.

I especially like the part about free goodies!

Spirit isn't going to make it to McCool Hill.

They have redirected the rover to a closer slope due to an impassable patch of sand between Spirit and McCool.  It's still 20 meters, though.

Please try to find out if the story was a novel or short story.  Also, if you can get any idea of whether the story was written before or after Mariner 4, we could narrow down the time it was published. 

I did do a quick database search for you.  So far, mixed news: In spite of the  plethora of stories about resurrected spacemen from that period (wierd!  :shock: ), I found no plot summaries that matched what you're describing.  Most of the bibliographic databases available only track these stories back to about 1980, so it proves nothing by itself, but does show that this particular dramatic device is at least rare.  So, the point about believing they're the first expedition and finding a dead astronaut when they get there might actually be sufficient to identify the story.

This is not a Ray Bradbury story. (Bradbury's stuff has apparently been catalogued to death, and, preferring resurrected spacemen, he never wrote a story along those lines.)  It's probably not a Robert Heinlein story, either.

If calcium is rare, then don't use it as a structural material.  It's required for portland cement, true, but there are many other cement blends available.  Sorel cement, for example, is a magnesia cement - a cement that uses magnesium oxide rather than calcium oxide to produce a binder.   It has about the same strength as portland cement, has a similar mix, and is produced using a similar process.  I'm not saying you just hold the quicklime out and throw the magnesia in to make sorel cement instead of portland cement, but it's darn close. 

We've found precious little magnesium carbonate on Mars so far (or anything carbonate, for that matter...   :? ), but there is clearly magnesium everywhere over there.  If you're just willing to forget about portland cement, you can have concrete on Mars.

:oops:

You might also consider the following public domain books.  They're a little old, but might still be helpful:

The Problem of Space Travel: The Rocket Motor

How to Design, Build and Test Small Liquid-Fueled Rocket Engines

Engines and Innovation: Lewis Laboratory and American Propulsion Technology

I also recommend the web pages and lecture notes available at MIT OpenCourseWare Project.

A perfect beginning.  Thank you!

All of the above.

ROTFL! 

*Sigh!*  Okay, I finally stopped laughing long enough to type. 

What we're seeing from Mexico is ultimately just another economically driven mass migration.  Sure, the Mexican government is responsible for driving its people out of their own country, and we're going to suffer a little for it.   So what?  Contrary to the current propaganda, we can absorb the influx.

In the end, they're just the new Irish.  In fifty years, their descendents will be running the country, and they'll be so assimilated that nobody will care. 

Bienvenidos to America.   8)

Would God we might see such a migration to Mars some day....

From the US National Hurricane Center at 4PM EST today:

I think the NHC's running out of things to say in their public advisories.  Hopefully we'll have at least a few months until "Alphonso".  Don't quote me on that, though...