It’s about to start. Note that this is not being done under the auspices of the socialist seabed authority under the Law of the Sea Treaty.
Category Archives: Business
Capitalism In Space
I have a piece up at National Review Online today, on the current state of play in human spaceflight.
The Lost Decade
If these stories are true, it explains a lot.
The Drug War
…is criminally insane.
Popping The Higher-Education Bubble
With Obama’s war on the suburbs.
If so, it seems like it would be poetic justice.
Meanwhile, In Mojave
In contrast to NASA’s unfortunate attempt today, Dave Masten is tweeting that they just flew Xombie 650 yards down range.
Back To The Drawing Board
Apparently Morpheus crashed and burned in its first untethered flight. Armadillo and Masten often make this stuff look easy, but it’s not.
[Update a fewminutes later]
Here’s the video. Sounds like a tank blew up after a few seconds. Single engine, so had to be a failure of the gimbal or the controller.
Statistics And The Failure Of Space Policy
Thoughts from Ed Wright on why we have to get space activities out of the hands of politicians as soon as possible.
Mars Spreadsheet Update
For anyone interested, I’ve got a new, improved version up. It’s basically more organized, with the constants grouped together, and with no references to rows below the formula.
My Mars Spreadsheet
As a response to popular request (actually, no one asked except Jon Goff), I’ve cleaned up and uploaded my spreadsheet.
Other than the astonishing results themselves, the only thing that makes me suspicious is that the total delta V required for the mission with the stop for gas is less than that required for the direct trip (about seven km/s for the latter and about six for the former). But I’ve looked at it multiple times, and don’t see anything wrong with what I did. I’m guessing that, if this is right, it has something to do with the oddities of patched conics. But it would be nice to get some more eyes looking at the problem.
[Update a few minutes later]
Don’t waste too much time looking at that. I just noticed some problems. I’ll update when I’ve fixed.
[Update a few minutes later]
OK, I’ve uploaded a new version. The good news is that I found the problem, and the total delta V is now more for the trip with the gas stop than without (which it seemed it should have been). It’s now about four and a half kilometers per second for the direct case, and about six for the gas stop. The bad news is that the advantage has dropped significantly. The propellant ratio, rather than ten and more than twenty for the EML1 and LEO cases without refueling, is now more like three and five. Still, it’s a significant improvement.
I should note that this is an excellent example of a need to have a feel for the numbers, and not just trust what comes out of a computer (as I fear too many young people do these days). If you don’t know intuitively proper orders of magnitude, or recognize suspicious results, you’re likely to make a lot of errors when doing complex calculations, particularly if you are operating in an environment of confirmation bias (I really, really liked the first, incorrect results). I’m looking at you, climate modelers…
[Update a few minutes later]
One more update to the spreadsheet. I noticed that in fixing the calculations, my delta Vs had become unbalanced, so I adjusted the gas station orbit slightly to rebalance them. The new orbit is 1.256 AU.