They did a full nine-engine static test of the Falcon 9 yesterday. No mention of burn duration, but I assume that it wasn’t a simulation of a full ascent. I also assume that they have run individual engines at full duration. If they launch Falcon 1 this weekend or early next week, it will have been a pretty momentous week for New Space, with the WK2 rollout, the rocket racer debut, and the SpaceX achievements.
Category Archives: Space
Unresolved
Clark Lindsey has the press release from Scaled about last summer’s fatal accident. Short version, by my reading: we still don’t know what happened and probably never will, so we’re just going to be a lot more careful in the future.
I still think that they continue to overestimate the safety of hybrids, and that it wasn’t a great choice for propulsion. I suspect that if Burt were starting from scratch now, he’d go with a liquid, but shifting to one at this stage would involve too large of a redesign of the airframe.
We Knew This Was Coming
John Glenn is arguing for an extension of the Shuttle program. I don’t really give a rip what he thinks, but a lot of people on the Hill (particularly on the Democrat side) will take him seriously. The problem is that it’s not just a matter of coming up with more money. NASA has to do pad modifications at 39 A and B to accommodate the new vehicles, and they can’t do that if they continue to fly Shuttle. I suspect that it will also start to get pretty crowded in the VAB if they’re doing Ares and Shuttle simultaneously.
Sometimes, I think that the best thing that could happen to American space policy would be a Cat 5 hurricane hitting the Cape, and scraping it clean.
[Update a few minutes later]
Here’s more from Robert Block at the Orlando Sentinel. Note the comment about there being no appetite on the Hill for a Shuttle extension.
[Update a few more minutes later]
Mark Whittington once again demonstrates his legendary prowess at reading miscomprehension. I agree with Jon (though I’m not going to vote for Bob Barr). As I said, probably the most effective (and perhaps necessary) step toward a revitalization of NASA would be a Cat 5 at the Cape. I don’t think that anything less can shake the space industrial complex up sufficiently to get any kind of new thinking or direction.
Missing The Point
Swashbucklers In Space
Alan Boyle has another report from Oshkosh (some people get the best gigs).
Griffin downplayed media reports about vibration problems with the Ares 1 rocket, saying that there were “half a dozen means to mitigate that” and that two top strategies would be selected for further study next month. “Let me put it this way: I hope this is the worst problem we have in developing a new system,” he said.
Of course he did. That doesn’t mean they aren’t true. I haven’t seen any ways to mitigate it that don’t involve a lot more weight and performance penalty on a vehicle that’s already out of margins. I too hope that it’s the worst problem they have, because if they have any that are worse, the program is in deep, deep kimchi.
Overhype?
Is this really as big a deal as NASA is making of it?
Data from recent missions to Mars has been building toward a confirmation of the presence of water ice. However, “this would be the first time we held it in our hands, so to speak,” says Bryan DeBates, a senior aerospace education specialist at the Space Foundation. Evidence from other locations in the solar system, including Earth’s moon, Saturn’s Enceladus moon and Jupiter’s Europa moon, have strongly hinted at the presence of water–NASA confirmed a liquid lake on Saturn’s Titan moon on Wednesday–but no direct observation of water has been made.
Haven’t we been pretty certain for years that there was ice on Mars (and outer planet moons, and comets)? What’s the big deal here? If there’s a story at all, it seems to me that it’s about the amount of water available, not the fact that we have “direct confirmation.”
To The Moon, Alice
One of the nice things about having a blog is that you can self publish. This is the original piece that I submitted to Popular Mechanics, which inspired them to ask for a “revision” which they then edited to what was actually published. I thought that readers here might appreciate it.
Location, location, location.
Those are the proverbial three rules of real estate. They aren’t restricted to terrestrial transactions–location matters a lot, sometimes a lot more, in space.
Recently, Michael Benson, a guest columnist at the Washington Post, proposed that the problem with the International Space Station is that it is in the wrong place. He proposes that it be refitted as an interplanetary spaceship.
It’s a novel proposal, and he’s in good company–a lot of people are thinking about what to do with the ISS after 2015, for which there is currently no official US policy. The foreign partners and other stakeholders recently met to discuss the issue, though if this particular option was discussed, there is no mention of it in the reporting, or the joint statement they provided after the meeting. There’s probably a good reason for that.
Mr. Benson is clearly earnest, but the concept is not as well thought out as he seems to think. The ISS is designed for operations in low earth orbit (LEO), but that is a unique environment, and had trips beyond that been its intended use, both the requirements and the design would have looked very different.
What does NASA think?
I called Mike Curie, in the NASA Public Affairs Office for the ISS, to get the official agency response. It was predictable, concise, and (in my opinion) correct: “We welcome and share Mr. Benson’s enthusiasm for the space station program, but the proposal is not feasible.”
He suggested that I talk to Tom Jones, four-time Shuttle astronaut (and Pop Mechanics space consultant) for further elaboration, so I did.
The idea has several problems,” he told me. “If you do it with chemical propellant, the structure won’t be able to take those high thrust levels, particularly the fragile solar panels that were designed for zero gee. Also, the Station isn’t designed to operate for long periods of time without resupply of things like food, water, and spare parts for maintenance. You’d have to develop a duplicate interplanetary system just to deliver the supplies and rotate the crew.”
“Once out in deep space, the ISS doesn’t have the radiation shielding it would need for either lunar operations, or even traversing through the Van Allen belts, particularly if you did it slowly with a low-thrust system, as he suggests.”
“The Station is also overdesigned for an interplanetary mission in some ways. It’s a laboratory facility designed to rely on frequent resupply and contact with Earth. This is not an operational space vehicle. It’s more of a technology test bed, to learn how to do things in space, and take advantage of the near-Earth space environment. It’s really better and more cost effective to keep it here and use it for what it was designed.”
In fairness, Mr. Benson attempted to anticipate these objections:
It’s easy to predict what skeptics both inside and outside NASA will say to this idea. They’ll point out that the new Constellation program is already supposed to have at least the beginnings of interplanetary ability. They’ll say that the ISS needs to be resupplied too frequently for long missions. They’ll worry about the amount of propellant needed to push the ISS’s 1,040,000 pounds anywhere — not to mention bringing them all back.
There are good answers to all these objections.
Well, he has answers, but they don’t seem to be very good ones. One wonders if he actually ran any numbers.
How much propellant would it take? Well, to leave LEO and go almost anywhere else, you need to have escape velocity. In orbit, that means adding about forty percent to your current speed of twenty-five thousand ft/sec, or about ten thousand ft/sec. The station weighs on the order of a million pounds. Assuming that you could provide the necessary thrust without snapping off the solar arrays, using liquid oxygen/hydrogen (the most efficient practical propellant combination we have today at a generous specific impulse (Isp) of 480 seconds (not far from theoretical), it would take almost as much propellant as the payload (over 900,000 lbs).
Now that’s not necessarily a lot–it would be a couple dozen launches of, say, a Delta IV, which might cost a few billion dollars. But the problem is that all that does is get the ISS out of earth orbit. It doesn’t have any way to park in orbit when it gets to the moon or Mars, or even an asteroid encounter. To do that it needs (in Mr. Benson’s words) a “drive system and steerage module” (whatever that means) which he hand waves off as “technicalities.”
You also need propellant. A lot of it.
That means that we not only have to accelerate the ISS itself out of LEO, but also all of the propellant that it will need at its destination as well, which would likely be many hundreds of thousands of more pounds. So we have to recalculate our escape, and now we need, say, a million pounds of propellant to send with the station to its destination, and another two million to blast the whole lot out of earth orbit. So now we’re up to many billions of dollars for the propellant delivery to LEO, even ignoring the “technicalities.”
Ah, you say, but he suggested using low-thrust high-Isp ion-propulsion systems, which will require much less propellant.
So he did, but he didn’t consider the radiation problem, as Tom Jones noted. You’d fry the crew and the electronics, including solar panels, in short order, even if you’re lucky enough not to be hit by a solar flare in all that time.
Considering all the other factors he explained, clearly, the ISS is built for LEO, and it should stay in LEO.
But that raises another question. Is it in the right LEO?
The ISS is in a 52-degree inclination orbit. This location was chosen in 1991, when it was decided to bring the Russians into the program, using some of their modules as the core of the station. At the time (and now) their primary launch site was Baikonur, and that was the lowest inclination to which they could launch from that location. The Shuttle pays a high payload penalty to reach that orbit (the original space station plan was to have it at 28.5 degrees, the same as the Cape’s latitude, so they could get there with a due-east launch and maximum payload). In fact, every vehicle that goes to the ISS would deliver more payload if it were in a lower inclination. With Russian plans to start launching Soyuz out of the Arianespace launch site in Kourou, near the equator, they will have the capability to get to almost any inclination, so the old Baikonur constraint will be gone.
It might be worth doing a trade study to see if its inclination could be lowered, using ion propulsion, over a period of months or years, as I suggested several years ago. This would avoid the radiation problems of sending it out of LEO by this technique, because the whole trip would remain in LEO, and in fact the radiation reduces with the inclination. This would not only save money on resupply costs (or rather, provide more payload for the same amount of money, because the cost of the flights is fixed, while their payload can vary), but also perhaps put it in a more desirable location to serve as a way station to beyond LEO. It would also put it to use as the test bed that Tom Jones pointed out that it truly is, proving out long-duration ion thrusters that might allow future vehicles to operate more effectively.
So it might be time to consider a move to a better neighborhood–just not one quite as out of this world as Mr. Benson suggests.
Debut Of The Rocket Racer
Alan Boyle has the story of yesterday’s demo in Oshkosh.
Whither ISS?
I have a new piece up over at Popular Mechanics on the future of the space station.
Also, it’s the fiftieth anniversary of the signing of the Space Act, creating NASA.
[2 PM Update]
Here’s another rollout story at PM, with a lot of pics. It’s the current front page of the on-line version, along with my ISS story.
Potemkin Rocket Test
More on the “flight test” of Ares 1-X, which seems to be mostly for show. Though if it’s as risky as indicated here, it may be a more spectacular performance than they count on.
Unfortunately, the same folks who think a flight dynamics test of a four segment SRB with a different propellant, old-style grain design, and inert (that is to say, non-sloshing and stiff) upper pieces is a good idea also thought they could grab a bunch of used equipment (Atlas avionics software, Peacekeeper hardware, etc.), chewing gum, and duct tape (perhaps FEMA is helping the minions) and use it to demonstrate how something “like” ARES-1X might get off the ground after “the gap” has widened to its furthest extent.
And, like all of the shortcuts the Emperor’s minions have taken to date, this approach, too, is soon to come back and bite them. The list of critical components going into ARES-1X that are either beyond shelf life or being put to work in an environment for which they were not intended is astounding. And the risks that are being accepted, because of schedule and budget pressures, are equally marvelous.
Hey, it’s OK. That’s what waivers are for.