The U.S. is borrowing (currently with an interest rate of about 2%, pretty much the same as the inflation rate, so zero real cost) 39% of what it is spending.
http://www.cbo.gov/ftpdocs/120xx/doc12039/HistoricalTables%5B1%5D.pdf
We went from a surplus at the end of the 1990s to where we are now, due almost completely to 1. Tax cuts started in the Bush administration and expanded in the Obama administration 2. The 2008 financial collapse, which led to people falling into the safety net and reduction in profits/revenue 3. War in Iraq and Afghanistan.
http://www.cbpp.org/cms/index.cfm?fa=view&id=3036
Without those 3 factors, we would have virtually no budget deficit right now.
The NASA budget is about 0.6 % of the federal budget. About 30% of NASA's budget goes to science programs including uncrewed planetary exploration like MER or Curiosity, and most of the rest goes toward manned space exploration.
http://lunar.colorado.edu/~jaburns/archive/astr4800dec07/Lectures/NASA_Budget_BDavis.pdf
Curiosity costs about 2.5 billion altogether, but that's around what Orion is spending every year, (admittedly, some of which is going to me). The price tag for Curiosity is so high partly because JPL messed up and missed its launch window 2 years ago because of technical problems, and so a lot of the engineers were getting paid an extra 2 years for the same program. That's the first time that a funded planetary exploration program has missed its launch window. Orion is so expensive because the manned space side of NASA is in a whole different category of inefficiency compared to the robotic side.
Mars Pathfinder was budgeted for $150 million and ended up costing about 250 million.
The price tag for The Mars Polar Lander and the Mars Climate Orbiter, together, not including the launch vehicle, was about 125 million. With the launch vehicles it was about 250 million. The team was stretched seriously thin, and that had a direct bearing on the fact that both of them failed. MER cost about 800 million, including the launch vehicles.
Getting back to the original topic....
Adrian: I appreciate your perspective and insight on this mission. It's interesting to hear about the pros & cons of the various approaches.
But, even speaking as an aerospace engineer -- wow, is that a complicated landing sequence!!!!! And, it's made vastly more complex by a) the need for 100% autonomy due to the light-time delay, and b) the impossibility of full-up testing due to the different gravity & atmospheres on Earth vs. Mars.
It seems to me that even an "old-style" lander (in the vein of Viking, or Apollo), though still complex, has the big upside of being basically a single system once the heat shield comes off. This sequence has so many different kinds of events, each based on so many different sensors and timed sequences....each requiring (I assume) redundant components....
Particularly in the very risk-averse climate that NASA and the rest of the industry operate in, I'm surprised that this landing approach was approved. Was the weight penalty of an "old-style" lander really that severe? I would think that the descent stage needs to carry nearly the same amount of fuel whether it hovers 60' above ground for a minute or so and then flies away vs. actually landing.
For spacecraft that don't have to move around after landing, then I agree a fixed propulsion system is the way to go. The main reason why Viking/MPL/Phoenix style landing wouldn't work for this mission is because the payload is a really big rover.
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As complicated as Curiosity is, MER was actually significantly worse. In addition to the airbags, it had a big lander structure to protect it under the airbags, a Rover that had 56 (!) motors in order to unfold it from being packaged in that tetrahedron, a landing radar, 3 solid rocket motors, a tether that lowered the lander from the backshell, a camera vision system that adjusted the angle of the solid retro rocket motors to compensate for horizontal velocity, motors to reel in the airbags, motors to unfold the petals, a whole active cooling loop to keep the rover cool inside its airbag cocoon on the way to Mars, and I could go on and on. Check out this video:
Seriously, when are we going to put a Jeep up there and do some donuts? Enough with the R/C cars.
Edward
Anybody got any drawings showing how the Apollo moon buggy folded up and fit with the lander? It seems relatively large, but it would be nice to see a comparison of it vs. current Mars rovers, in terms of size, weight, unfolding complexity, etc.
-Ken
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