Jeff Foust, on the upcoming test of the five-segment SRB.
What a waste of money. If they insist on using these monsters for a heavy lifter, it will be so heavy that it means a new crawler and crawlerway at KSC. But they’ll get lots of jobs out of it, I guess.
…to the moon. Thoughts from Dennis Wingo (who I’ll probably see in Anaheim this week — maybe even today).
This reminds me of Mike Griffin’s ridiculous comparison of Constellation to the Interstate Highway System (not to imply that Dennis’ analogy is in any way ridiculous).
It seems to have become my full-time job to correct this kind of thing. As for the notion that the new space policy “ends human spaceflight,” I feel like I’ve been playing whack-a-mole with that nonsense since February.
Were the dinosaurs wiped out by a dual strike?
…aren’t done yet. I wonder if transonic combustion could improve the performance of rocket engines as well?
So, I was reading comments at this post from yesterday, and Ed Wright mentioned some of von Braun’s death-bed regrets. Curious, I did a little searching, but all I came up with (so far) was this bit of lunacy from Carol Rosin.
…of popular support for Apollo — a blog post by Roger Launius from a few days ago.
I would point out, per Gene DiGennaro’s comment, that the popularity of space-related toys tells us nothing about the degree of public support. If only ten percent of the kids like space toys, that’s still a huge market.
In my talk at Space Access in April on the “Impedance Matching” panel, I raised the issue of how to completely decouple atmospheric vehicles from pure in-space ones. That is, right now, all paths to LEO seem to go through a launch pad, even coming back from some place else (e.g., the moon or deep space). This is because it’s difficult and expensive to circularize there from places less deep in the well. It’s difficult to do aerobraking safely and reliably in a single pass, and multiple passes means that the maneuver can take a long time, which can be a problem for crewed vehicles. And of course, this doesn’t even address the issue of getting into the right orbital plane. But until we can fix this, we’ll always have the ugly and inelegant situation of having to come all the way back the the earth’s surface from any beyond-LEO destination, and have to spend resources relifting crew for each trip, and make a true transportation node in LEO (i.e., one that can be reached from any destination, either from the surface or in space) impractical.
Anyway, I’d like to see what kinds of ideas get kicked around in comments here, perhaps with the hope of doing a presentation at the SSI conference in October.
[Afternoon update]
Circularizing propulsively is of course an option, but it’s hard to see how it’s a cost-effective one, until propellant in space is really cheap. Assuming that one doesn’t aerobrake at all, it takes just as much delta-V to get into LEO as it does to leave it, and it would require an improbably large vehicle if the departing vehicle has to carry enough propellant to recircularize on the way back. Which, of course, again demonstrates the value of depots. With one at L-1, perhaps supplied from either the lunar surface or an asteroid, it might make sense to fuel up there for the circularization in LEO. It all comes back of course, to the point that I made in my essay last year — that reusability implies gas stations, and that it’s impractical without them. As Jon Goff demonstrated with his amusing “We don’t need no stinkin’ depots” slide at Space Access, which was a picture of his car with extra gas tanks for driving cross country, the more often you can fuel on a trip, the smaller your vehicle can be and, due to the exponential nature of the rocket equation, that goes in spades for space vehicles.
[Bumped]
Trent Waddington has a post about the potential for early asteroid missions.
Clark Lindsey has compiled a list of links to reviews of the book