Category Archives: Space

Business, Political Commentary, Space

Bad News For Commercial Space?

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Fox News is reporting that Bill Richardson is withdrawing from the Obama cabinet as Secretary of Commerce, probably over his pay-to-play problem. He was perceived by the space community as someone who would provide full support for the department for commercial space, based on his record of supporting space tourism and related ventures as governor of New Mexico. I wonder if the transition team had some backups to go to, or if it will be a while before we know who will replace him?

[Update a couple minutes later]

Jeff Foust is already on the case, with linkage.

General Science, Science And Society, Space

Free Fall

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As Clark notes, here is a very nicely written piece on parabolic flight and weightlessness. Rare is the reporter (even science reporters) who get the physics right on this, because (as he points out) they get confused by the phrase “zero gravity,” which doesn’t really exist anywhere in the universe. Only one quibble:

Each period of ‘weightlessness’ is limited to half a minute or so; otherwise we ‘zeronauts’ would continue freefalling right into the Nevada desert at 600mph. As it is, during half-a-minute’s power- dive we drop nearly 20,000ft – although inside the plane we are completely unaware of this.

This gives the impression that weightlessness only occurs when you “drop” (i.e., descend in altitude). But it actually happens on the way up as well. In both cases, you are “falling” (in the sense that there is no force acting on you other than gravity). First you fall up, then hit the top of the trajectory, then fall down, weightless all the while, and unable to discern your direction of motion. If this seems counterintuitive, it is. But consider an elliptical orbit. As you approach perigee you’re heading down (toward the earth), and once you reach it, you start heading back up (away from the earth) to apogee, but you’re in orbit, and free fall the entire orbit. A parabola in an aircraft is an orbit that, if continued, would intersect the earth’s surface (which is why it is wise to not continue it). And of course, to be more technical yet, it is only parabolic in an approximate sense (assuming flat earth). In reality, it is a tiny section of an ellipse, because the contents of the aircraft are (briefly) in orbit, within the atmosphere.

I should also note that the phrase “power dive” is also misleading. “Power dive” implies that you are diving with engines at full thrust to get down as fast as possible, but in fact, the engines are barely running above idle throughout (until the pullout). Their only function is to overcome wind resistance so that the aircraft can approximate a cannon ball falling in vacuum.

Political Commentary, Space

Shuttle, Ares and EELVs

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There are some interesting top stories over at Space News this weekend. First, there is discussion of the results of the Shuttle extension study, which says that it would be possible to extend Shuttle all the way to 2015 without impacting Ares development, as long as additional budget was provided. One of the biggest arguments against it is the risk of losing another orbiter:

According to the study, both options increase the risk of losing a crew or vehicle: The two-year extension increases the cumulative risk from a 1-in-8 probability to 1 in 6; extending operations through 2015 increases the risk to 1 in 4. The risk of losing an orbiter or crew on any given mission is 1 in 77, the report said.

I know that in the past NASA has been too optimistic about probability of crew/vehicle loss, but I think that 1 in 77 is probably too conservative now. I suspect that, post Columbia (and resolution of the foam issue and ability to inspect and safe haven at ISS for all missions other than Hubble), the Shuttle is probably as safe, or safer to fly now than it’s ever been. That’s not necessarily an argument not to retire it, but I don’t think that the risk of vehicle or crew loss is a compelling argument against extension, either.

I would seriously dispute this comment from Mike Griffin:

In a Dec. 15 interview, Griffin called reliance on Soyuz “unfortunate in the extreme,” but said NASA needs the $3 billion it spends annually on shuttle to move ahead with the replacement system.

“Every time I have spoken about [the gap] I’ve laid it at the feet of budget,” Griffin said. He emphasized that without an increase in NASA’s overall budget, extending shuttle operations will result in a corresponding delay to Orion-Ares 1.

I’ve got a better set of feet to lay it at — Mike Griffin’s decision to develop an unneeded new launch vehicle, which was not intended within the vision or the budget “sand pile.” He knew what the budget was going to be, but rather than moving out on developing actual exploration hardware, and encouraging private industry to get people to LEO via COTS D or something similar, he decided to take that money and develop Ares.

Speaking of which, he appears to be losing the battle to save it:

Griffin said NASA also explored the possibility of developing a larger rocket based on EELV hardware and systems. “We went through it and we came up with the answer that the EELV-derived solution didn’t save you any schedule, didn’t save you any money, wasn’t that safe, and when you look at going beyond the space station mission to the heavy-lift architecture, was quite a bit more expensive. So it didn’t win on any count,” Griffin said. “At this point I’m kind of wondering what has to happen to have people say, ‘OK, I guess they got it right.'”

No need to wonder, Mike. Here’s what has to happen. Show us the actual results of the analysis, along with the assumptions. Then we’ll be able to decide whether or not “they got it right.” Until you do so, we will remain (appropriately) skeptical. It’s too big a decision, with too many implications for taxpayers’ dollars, and our future in space, to just take your (and Scott Horowitz’ and Doug Stanley’s) word for it.

Finally, there is a story that claims that the Orbital proposal for COTS, which was the highest cost, was also the lowest rated. Given Dr. Griffin’s history (and potentially future) with OSC, this will be sure to raise some eyebrows. Particularly since it looks like Planet Space is going to protest. Charles Lurio notes via email that he has a source who claims that:

…a reason for rejecting Planetspace was that Griffin didn’t want an EELV to be used, since, though the only flights would be unmanned, it would further underscore to people that EELV was a viable alternative to Ares 1.

At the time, it sounded like an extreme story even given Griffin’s mania to save Ares 1.

Now, with the comment in the Space News item that Orbital had, “the highest price and lowest score,” I’m starting to think that the story may be a lot more plausible.

Unfortunately, it may be. He’s really on the defensive.

Clark Lindsey has more.

Political Commentary, Science And Society, Space, Technology and Society

Death From The Heavens

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Was there a major meteoritic strike 13,000 years ago in North America?

That wasn’t very long ago (compared to, say, the sixty-five million years ago that the Yucatan was hit). Evidence continues to accumulate that we get hit a lot more than people have previously imagined. We really need to develop the capability to do something about it. We have technology in hand to do so, but apparently lack the will to deploy it. This by itself is reason enough to make the investment to become a real spacefaring civilization, but pork and maintaining existing jobs remain more important.

Administrative, Political Commentary, Space

Have It Your Way

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This has actually been true since I switched to Word Press, but it’s now possible to view specific category posts. For instance, by clicking on the space category, you can see only space stuff (for those who have complained over the years that they like my space posts, but aren’t interested in, or are put off by, my political posts). Likewise, those who like the politics without the space can use this page instead. Or any of the other categories, though those two are probably updated most often. Same thing applies to people who have me on their blogroll as a service to their readers, but don’t necessarily want to subject them to what they might consider off-topic blather (e.g., Alan Boyle or Clark Lindsey, or Jon Goff might only want to blogroll the space category).