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Comment Re:HDR? (Score 1) 287

You're probably the first person I've run into who can describe what's going on in such images well enough to convince me that you understand it. I was going to try to explain it myself until I saw your post. The comparison of local contrast to proper brightness mapping is much more concise than anything I would have come up with.

Comment Presentation versus Research Paper (Score 1) 206

I see nothing dysfunctional about this.

They don't want to release the data they spent the last several years developing a system to collect until they have a chance to study it and write the first papers from it. In the meantime, there's nothing preventing them from talking in general terms about the sorts of things they're finding. Saying there appears to be 400 earth-sized candidates isn't going to allow anyone to beat them to getting credit for analyzing the data.

Comment Spain doesn't get 41% from wind (Score 1) 506

According to the CIA World Factbook, Spain uses about 276 billion kW-hr per year. According to Wikipedia, wind in Spain generated 36 billion kW-hr in 2009, which is growing at around 10% per year.

That's 13%, which although I don't read Spanish competently, I think is what your link says. It's still one of the highest shares of any nation, but definitely not 41%.

I'm sure you got that 41% number from a recent story about during a time of unusually strong winds and the low demand period at night, wind made up 41% of the generation for a couple hours.

Spain can handle this because huge regional overcapacity like the Pacific NW does, they don't have a large fraction generated by dams that are required by the EPA to keep flow rate through the turbines at minimum levels for salmon protection, and around half of their generating capacity is from natural gas, which can quickly adjust output to meet changes in supply or demand.

At the same time, they pay on average about twice what we do in the US, partially because wind and gas are expensive.
Space

Submission + - NASA Returning to the Moon with First Lunar Launch (nasa.gov)

epedersen writes: NASA's Lunar Reconnaissance Orbiter launched at 5:32 p.m. EDT Thursday aboard an Atlas V rocket from Cape Canaveral Air Force Station in Florida. The satellite will relay more information about the lunar environment than any other previous mission to the moon. The orbiter, known as LRO, separated from the Atlas V rocket carrying it and a companion mission, the Lunar Crater Observation and Sensing Satellite, or LCROSS, and immediately began powering up the components necessary to control the spacecraft. The flight operations team established communication with LRO and commanded the successful deployment of the solar array at 7:40 p.m. The operations team continues to check out the spacecraft subsystems and prepare for the first mid-course correction maneuver. NASA scientists expect to establish communications with LCROSS about four hours after launch, at approximately 9:30 p.m.
NASA

Submission + - STS-119 Launches into Space...Finally (thefutureofthings.com)

Iddo Genuth writes: "After several delays, including twice over the past week, the space shuttle Discovery has finally been launched into space. The spacecraft took off at precisely 7:43 p.m. EDT, embarking on the STS-119 mission, which will provide the International Space Station (ISS) with the fourth and final set of solar arrays. The shuttle will also deliver to the ISS its newest crew member — Japan's Aerospace Exploration Agency astronaut Koichi Wakata, who will replace flight engineer Sandra Magnus at the station."

Comment Re:"again"? (Score 1) 98

Ahh...good thought, but not the case here.

This area isn't chilled down until fuel loading begins, and I believe that is just done by sending LH2, or possibly a brief helium purge, through at low volumes for a while...I think only 30 minutes. Then they just pumping it in at full volume until its full. I guess that's slow enough that thermal stresses aren't an issue, and contraction is dealt with in the design. The main concern is boiloff, but the thermal mass of the fuel is far greater than that of the tank, and the fuel is kept topped off until just a few seconds before launch. At the time when fueling begins, there's no access to the external tank, so I know for certain that no retorquing is done then.

Comment Re:"again"? (Score 1) 98

Maybe it has something to do with cooldown times for components exposed to liquid hydrogen at -423 F.

According to a Mission Management Team memo (not officially published, but there happen to be a couple outlets good at getting details), it's torquing issue. Here's the specific quote I was referencing:

In the reinstallation of the flight seal, there is a 30 hour retorque requirement, that pushes us to a Monday launch. The team is looking to examine if there is some wiggle room in the 30 hr torque requirement, then we could potentially get a Sunday launch attempt.

Cooldown is part of the overall filling process and done during the countdown at T-6 hours. It lasts about two hours.

Comment Re:"again"? (Score 5, Interesting) 98

This mission was originally supposed to launch February 12. I know, because I bought tickets to go see it, and I ended up missing (KSC still makes for a great vacation though).

They got within a week or two of launch, and decided they still weren't happy with the analysis that had been conducted for troubleshooting an issue with the propellant lines that cropped up during Endeavor's STS-126 launch. A valve on a secondary fuel handling line had failed, and while it didn't appear to affect that flight there was concern that it would either result in metal particles from the valve causing issues downstream, or lead to excess hydrogen venting that could cause a fire. They spent the last month testing and quantifying the probability of these concerns, and figuring out additional safeguards to implement for this flight, since making new valves would be an additional two months.

The next possible launch window is about 23:30 after this one, but apparently the expected resolution for the leak is a multi-day process. The launch is now scheduled for no-earlier-than Mar 15 (19:43 EDT), but Mar 16 (19:21 EDT) sounds likely. As I understand it, re-installing the ground support hydrogen line on external tank requires a 30 hour waiting period before applying the final torque to allow the seals to compress...a typical factor when working with torque specs on plastic components. That 30 hours is on top of the time to demate and remate the hydrogen line, do leak checks, and reset to the proper point in the countdown.

Anyway, because they're working against a launch window before the next Soyuz launches to the station, they're losing at least one mission day, and if it slips to the 16th, they'll be losing another day, plus one EVA. That will mean they can get the last solar array installed, but not fully hooked up. I'm not sure if that EVA would be handed off to a future shuttle mission, or if it could be fit into the station crew's schedule. If the launch happens after Mar. 16, they'll have to wait until after the Soyuz mission.

There's a briefing going on regarding all this right now on NASA TV.

Comment More a matter of Orbit vs. Ground (Score 2, Interesting) 325

In a polar orbit like OCO would have been in, the satellite would regularly cover the entire earth's surface. The rovers had an expected range of a few hundred meters. Even the amazing dozen kilometers they've covered over their extended missions leaves each still within the major geological features they landed in.

The insurance policy of having a second rover for moderate (not minimal) cost was one factor. I think it increased the costs by about 25%, and put considerable extra strain on the team to get the second unit built in time for the launch window. Launch cost alone was an extra 10% or so.

The other factor was that a second rover allowed them to conduct similar studies of a much different location on Mars, giving the scientists good comparisons of very different geographies. It turned out to be a good thing, too. Opportunity, which landed second, has arguably accomplished much more than Spirit, in large part due to its location. That's not to say that Spirit hasn't also been extremely successful, but Opportunity has tended to steal the spotlight since day 1.

A second copy of OCO would have been producing nearly identical data as the first. Given that this mission was already under pressure just from politics, spending extra money to build a complete spare was unlikely.

However, NASA still has the design work done. We'll have to see if they decide to build a replacement, or simply settle for data from the related Japanese Greenhouse Gasses Observing Satellite launched last month.

Comment Re:Eleven Years? (Score 3, Interesting) 168

The missions back in those "good old days" of space travel were much simpler both in scope, technical complexity, and duration. The longest of the Mariner missions, for example, was about 8 months, and it was only collecting data for a small fraction of that. We've already learned most of what we can (or at least what we can justify the cost of a launch for) with those simpler missions. This new Europa mission is going to be big. Even in physical size it will dwarf those old transistorized tin pots. NASA calls missions like this "Flagship" class. They are few, far between, and generally bring in floods of new information. This mission is on the scale of Voyager and Cassini.

Even back in the Voyager days, when the rocketry and resources (developed in the lull between Apollo and Shuttle) to launch such a mission were newly available, close visits to any of the planets beyond Mars were completely unprecedented, and NASA was anxious get underway it took five years. Cassini was first proposed 15 years and approved I think 10 years before it launched. Now that there's minimal hurry and a lot of other things to share the annual budget with, so the timeline is more like that for Cassini. The taxpayers don't want to pay out more per year, and besides, Europa isn't expected to go anywhere in the meantime.

As mission complexity and cost grows, getting the most out of it becomes increasingly important. You can't achieve that with a generic bus because it limits the instrumentation you can hang on it. Instead you tailor the bus to the power, thermal, geometric, stabilization, and other needs of all this really expensive and fancy instrumentation. If you need a 3-axis stabilized, nuclear-powered spacecraft with a large contiguous cavity for a big telescope like Cassini, you can't make effective use of a solar-powered spacecraft bus designed to be spin stabilized and provide a mount for a radar and a long magnetometer boom like Juno.

Instrumentation is another thing. Back in the Mariner days, they were generally taking the best instruments currently coming out of the labs and figuring out how best to use them for the mission. Lately, it's been more typical to examine what you want to know, what technically should be possible, and do the research, development, design and testing of an instrument optimized for its mission. As a result, science package development is often a primary pacing and budgeting concern for exploration missions these days.

Lastly, those ten Mariner probes in ten years were being concurrently developed, not one after the other. I'm not sure how many missions NASA had active or in development at any given time back in the 60's and 70's, or how much money was devoted to them. Right now, however, I'm aware of 13 solar system exploration missions currently operating, and five or six more in development. I'm really not sure how many earth and deep space observing missions there are (Hubble, Spitzer, Chandra, GALEX, WMAP, OCO, JWST, etc). All of these consume (I count 60+ total on NASA's website) consume less than a quarter of NASA's budget. It's rather impressive in the grand scheme of things.

Comment Re:Unlikely that Evergreen will get one (Score 1) 197

Absolutely...I don't think it's at all far-fetched. They genuinely have a great museum, and I'm sure with the addition of the space exhibit hall (new since I've last been there) it's even better. Between that and their active leadership they'll likely end up on the short list of candidates. But my personal opinion is that NASA will ultimately choose museuems with a more direct tie-in to space exploration (Evergreen Aviation itself is just a small air freight company) and more conveniently located for a larger number of people.

Of course, since I live in Portland, I would be ecstatic if Evergreen were granted even Enterprise, much more so for one of the operational orbiters.

Comment Unlikely that Evergreen will get one (Score 3, Informative) 197

I can't find the original information, but I'm pretty sure the allocation of the shuttles won't be soley based on cash, but also on perceived value to the public for receiving one and consistency with the general mission of the museum. Keep in mind, the $42 million is supposedly for refurbishment for display, not to raise additional money. This first of all will mean cleaning up any potential hazards, like residues of hydrazine manuevering fuel. Of course, they get fairly weathered by each launch and re-entry, so there'll be some polishing to be done, and undoubtably ITAR-sensitive or high value equipment like the main engines will be removed and replaced with detailed replicas where applicable.

There's three orbiters surviving (Discovery, Atlantis, and Endeavor). I suspect Kennedy Space Center will keep one and house it near their Saturn V that's on display. This is consistent with another article that says two orbiters and six engine display kits will be made available according to the RFI. With public accessibility being a likely major consideration, the Smithsonian Air and Space Museum is almost guaranteed one of the actual orbiters, to replace the Enterprise aerodynamic test vehicle which is currently housed there.

That's going to make it a tough grab for the remaining orbiter. Because McMinneville is roughly an hour-long drive from the relatively small and aerospace-vacant city of Portland, I think their chances of getting an orbiter are relatively slim, even though they have a great facility and can probably afford it.

The Intrepid Museum in New York Harbor is certainly prominent enough, but they would need to make a rather substantial addition to protect the shuttle from the elements. It probably wouldn't be possible to deliver it to the waterfront an SCA flight to New York, but if they wanted to put it on a barge like the Concorde they have on site, they may be able to float it straight up from Florida that way. I think they're also at a disadvantage because there will already probably be two shuttles on the East Coast (Florida and DC).

I think Johnson Space Center in Houstan and Marshall Spaceflight Center in Huntsville are the two most likely locations not on one of the major coasts. Both of them already host two of the three remaining Saturn V's (the third is at Kennedy). On the west coast, I think the lead option is Boeing's museum of flight, partially because of their accessibility and ability to host a space shuttle, but also because of their involvement with the shuttle program (although that is due to their acquisition of Rockwell).

I would bet one of these three locations will get the third orbiter. That still leaves Enterprise after it leaves the Smithsonian, which only did glider and procedural tests, but would still be a major attraction. Maybe Evergreen has a chance at getting Enterprise, but I think more likely a second of the above three will get her. There is also a ground-test mockup called Pathfinder currently at MSFC in Huntsville that would likely get a new home if one of the orbiters went there, but it's only externally representative of the flight vehicles.

A commenter on another site had a fantastic idea, in my opinion: before sending the last of the orbiters to a musuem, use the SCA to take it on a tour of the US. This would be a great opportunity for millions to see it and the modified 747 together.

Comment "Alleged" is the key word (Score 1) 479

This whole fuss has grown out of a single post on the Orlando Sentinel blog. Granted it's a professionally written blog, but the post was based on third party reports about a conversation that those passing the rumors on about weren't involved in.

Griffin steadfastly denies obstructing anything, and has pointed out that every requested document has been provided on time. Garver refuses to comment on it.

I'd be willing to bet she went in with an attitude that Griffin was going to feed her everything that was wrong with Constellation, and she was going to take that back to Obama and get the program cancelled. Then we can return to using the shuttle and the Obama administration doesn't have to face the risk of overseeing a new and ambitious venture. Save the shuttle jobs (Florida voters), save a little bit of prestige of spaceflight, be the lady who stopped a broken program (Constellation is not broken, BTW. It can be fairly argued that it's not the best option, but it's well on its way to succcess), and as a result the US throws away 5 years of development work and sits on its butt for the next 4-8 years making freight runs to the ISS.

When a political science appointee jumps on a rocket scientist on the topic of rocket science, what do you expect to happen? The rocket scientist is going to get pissed. Griffin probably isn't the easiest guy for a politician to work with. There's been a lot of criticism directed his way, especially from armchair engineers not on the program who think they know something he doesn't. If a politician came his way and spouted the same things, I could definitely see him getting riled up.

This is a mess, based on hearsay and little more. Unfortunately, the Sentinel has blown it into a national story without documented sources. I'm not even worried about Griffin. He's a skilled engineer, but a mediocre administrator. NASA will easily survive if Obama gets rid of him. But if he sinks Constellation, mark my words, you won't see NASA accomplish anything front page news worthy until at least 2030, unless there is another accident.

Comment Clarification on the problem (Score 1) 29

I was a little worried when I noted in the article that the author was a disguntled ex-NASA employee. Then I realized who the author was: former Science Mission Director administrator Alan Stern. He's the guy who earlier this year was lambasted by NASA higher-ups and Slashdotter's alike for pulling the plug on the ailing Spirit Mars Exploration Rover to save a few million dollars. His decision was forcibly reversed, and being out of favor he resigned. Given my enthusiasm for the rover program, I find my mildly surprised to be sympathetic to his bitterness. He had a limited budget that was too small to support his growing assignments. In a way his decision about Spirit might have been a good thing, because it drew a lot of fast attention to the issue...but he got torpedoed for it and then the attention died away again.

The problem of delays and ballooning expenses is not an easy one. The mission teams aren't spending their days seeing how far fire extinguishers can propel them down a hallway on an office chair and doing a little bit of development work when it suits them. They're very frequently working their tails off and on overtime, and Homer Simpson walking by wearing Tom Landry's hat isn't going to magically inspire them to greater efficiency.

The main problem as I see it is that engineers and scientists generally suck at estimating work, and accountants and managers generally suck at understanding technology development to do much better. Add in the fact that cost presented is a big factor in which missions get chosen over all the other candidates, and you've got recipe for severely lowballed estimates.

Stern is suggesting a really painful fix, and I'm not sure I like it. Cancelling missions that are overbudget or schedule is a hard thing to do. He's right that the "we've spent too much to stop" argument is incomplete, and he's right that supporting wayward projects further encourages poor management, but that's only part of the picture. MSL was originally considered to be worth the $1.4 billion it was approved for. The true sunk-cost argument isn't that we've spent too much to stop now, it's that a mission that was worth $1.4 billion is definitely worth $700 million. We've spent the $1.4 billion, and we can't get it back either way. However, looking at the issue anew, for $700 million we can get a $1.4 billion probe.

But that's only one mission, it still allows the problem to recur, and it stealthily and unequally replaces the question, "Is this mission worth $2.1 billion?" with two questions, "Is this mission worth $1.4 billion?" and, "Is this mission worth $700 million?"

I really wish I had a good counterplan to Stern's argument that we should cancel missions that go overbudget and schedule, but I don't. I like to think that an independent NASA auditing group of experienced engineers and bean counters who don't have direct stake in mission selection would result in better initial cost estimates, but I'm not confident of it. Figuring out how much work inventing something new will take is a lot harder than figuring out how much work making something that's been made before like a car will take, and NASA already attempts this to a degree.

By the same token, I'm not sure Stern's plan will work. It might fail to spur better estimations of scope. Its only accomplishment in that case would be the cancellation of a lot of good projects after a lot of investment with nothing to show for it. The two missions he calls out most deliberately, MSL and the James Webb Space Telescope, are two of the most anticipated, by scientists and civillians alike, science missions on the board for the next 10 years. It would be a shame to kill them and not only fail to get any science return, but fail to fix the problem.

Comment Re:FP (Score 2, Interesting) 182

I work for the TX facility.

If I may ask a tangential question, how do you like working for SpaceX out at the test facility? I've been considering applying for one of the test engineer positions out there. Really, the main thing keeping me from doing so is the fact that it's way out in Texas (not because of the usual Texas cliches, but just because I like the Pacific NW too much). Anyway, how are the hours? Any major gripes? What sort of work do you do and what kind of background did you come from?

Thanks and good luck with the testing!

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