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Comment Re:The tapes were re-used (Score 5, Interesting) 307

It is suspected that the tape was re-used due to NASA's tight budget and they couldn't afford more tape.

Not just budget concerns. There was also a big problem in the 80s when commercial whaling was outlawed. The tape that NASA had used to record a lot of data involved whale oil in its production somehow. When whaling went out, whale oil went away, and companies that made data tape scrambled to replace it with something. They came up with synthetic alternatives, but because they didn't have much time to test, they discovered after it was already in use that the new stuff basically turned into glue after sitting on a shelf too long, which ruined tapes. So the old whale oil tapes became valuable for re-use, since you could depend on them not gluing together and losing all of your data. So that's another reason why NASA taped over a lot of irreplaceable data.

At a conference last year, I spoke with a NASA guy who was working on recovering a lot of old lunar data. He told me about the whale oil angle. He also said their best find at that point had been a whole palette/palettes of the whale oil tapes that had been sent from one NASA group to another to be copied over, but had been misplaced in a warehouse during transit, and just sat there ever since.

Comment Re:Awesome, you can approximate the speed... (Score 1) 45

Okay, but look. The ISS roughly repeats its orbital path roughly every 3 days, taking a 5-meter resolution image. Landsat is 16 days and 15 meters. RapidEye is 5 meters at 5 days (or daily, if you are okay with some pretty oblique photos). MODIS is every 1-2 days, 250-meter resolution. There are many other options, but you get the idea. You choose your instrument based upon the needs of your project. If you're imaging the northwestern US in the summer, and you're interested in being able to check up on some phenomenon at a temporal resolution that's pretty short and a high spatial resolution, Urthecast may be a good choice. You could use RapidEye, but in my experience, it's crazy expensive. I don't know what Urthecast costs are. If you just want to see something like % cloud cover of the Earth daily, MODIS will work and is free. If you want to see land use change since 1980, you go with Landsat because it goes back so far.

If it's cloudy, then you won't get good data, but that's basically true of all satellite imagery, unless you are doing some application that uses EM bands that pass through clouds easily.

The other option is chartering aircraft or using drones, and aircraft are super expensive and drones are a lot more DIY. But those might be the best instruments, like I say, depending on your project.

Comment Re:Traffic? (Score 5, Insightful) 45

It appears that individual cars are at just about the spatial resolution of the camera. Figure a car is something like 2 meters by 5 meters. Urthecast's camera, 'Theia', is advertised as a 5-meter camera (5m x 5m on the ground). So a car only takes up about half of a pixel. Which means that when the CCD is exposed, sometimes the pixel comes out white for a white car that happens to align itself totally within one cell of the CCD, and sometimes the car 'disappears' when it is overlapping two cells and is not increasing either cell's reflectance enough to make the cell come out white. (Note also that we only really see white cars; if you look very closely you may be able to see darker colored cars also, but they mostly blend into the road because they are not differently colored enough).

Theia is also a 'pushbroom' camera, which means that its CCD array is a linear array that is swept over the field of view (likely with a mirror or similar). Furthermore, the camera itself is moving through 30 degrees of arc while focusing on one area of the Earth, which means that as the CCD is imaging each linear set of pixels, it's moving within a camera that is moving on board a space station that is moving with respect to the Earth. So there is a *lot* of image processing going on to turn this collection of pixel rows into a coherent video. Some of that processing is likely to involve lossy processes and interpolation that provide a second source of this 'disappearing car' phenomenon.

Comment Re:What is being missed... is the $2 million part. (Score 1) 456

'they' probably means the local government union objected to a non-union project.

Could be. On the other hand, it could just be because they'd like a system with a formal service contract, warrantee, liability insurance, etc. Having some former student come back to the school occasionally to perform incantations over a Commodore may not inspire great confidence that the system is well in hand. What if something goes horribly wrong with the system and causes damage to the building? May not be Jeff's fault, but Jeff may be involved in the legal fallout.

Comment Re:Security is a process - not a tool (Score 1) 203

What a bunch of delusional macho BS. When was the last time you actually saw someone grab a gun and go be a "first responder" to a crime? You haven't.

There was an incident in my town a few years ago in which a guy shot some people and barricaded himself in a building. There was one citizen who took it upon himself to grab his gun and go be a "first responder" to this crime. The barricaded man shot him, and then it was up to the police to try to remove the would-be hero safely from the area in order to get him medical treatment.

So, anecdotal evidence that people do grab a gun and attempt first response, but it doesn't always go quite the way they imagined it would.

Comment Re:And I'm the feminist deity (Score 1) 446

Yeah, it seems to me that we have done a few things that make young people's lives a bit worse:

First, we have this credential inflation going on, where businesses are requiring four-year degrees for jobs that might have only needed two-year degrees or even just high school just a few decades ago. Being a secretary or file clerk or whatever hasn't become more difficult, but for some reason we now expect applicants to have a degree?

Second, the cost of college has blasted off way above the rate of inflation. Some people say that's because of the availability of education loans, and maybe that's right; I don't know. But the value proposition changes as college becomes more and more ridiculously expensive.

Third, we seem to like to tell kids that they can do whatever they want, be whatever they want to be, and everything in their lives will work out. Realistically, why does my university even offer a BA degree in theatre? It's not a well-known program; there are no well-known professors; there are very few famous graduates. I doubt if 10% of the program's graduates wind up working in theatre.

It is a disservice to our undergrads to represent programs like this as good preparation for a job in their chosen field. But I'd say that as long as we make that clear, that what those students are really getting is bit of socialization and practice at working and managing their lives, combined with a BA degree that may get them past the first cut at HR for a somewhat menial job, then we have warned them enough.

What I'd really like to see is a significant paring down of the diversity of undergraduate degrees. I think there's too much specialization, especially in liberal arts and social sciences (of what practical use is an undergraduate degree in, say, psychology, if one doesn't plan on going to grad school?).

Comment Re:And I'm the feminist deity (Score 1) 446

I knew a girl who did this not that long ago; she had a full-ride scholarship, and what did she blow it on? Theater. Did she get a job in theater? Nope; she moved towards make-up and costumes in her senior year thinking that would be a more realistic career path, graduated, and ended up working at a hotel in customer service. A complete waste of a degree.

But is it really a complete waste of a degree? Is four-year college only valuable as a vocational program, or might there be advantages to general education, a particular social environment, and so on?

Comment Re:Interesting... (Score 1) 85

I don't think the Department of Education has an enforcement division

Actually, I was recently surprised to learn that the Department of Education does have an enforcement division, and that they are armed with Glock 27s and Remington shotguns.

Here's an article with some of DOE's purchase orders over the past several years:
https://www.muckrock.com/news/...

Comment Re:Controversial because? (Score 1) 284

I'm so glad to see your comment. I don't have a strong opinion about Common Core, being neither a teacher or a parent (though I am favorably disposed toward it). But I do believe that we should argue the merits of CC on their own, without complicating the discussion with standardized testing and teacher evaluation. Those two are important issues, but they are not Common Core. It's frustrating to me that CC has somehow become a partisan issue, and that there is so much wildly manipulative misinformation swirling around the topic.

I am also generally in favor of reducing the number of standardized tests that students take. And I believe that teacher and school evaluation is an issue that must be taken on, but I don't know what the best approach would be (though I'm fairly certain that NCLB and the like is not it).

Comment Re:So what? Feel free to move into a cave. (Score 1) 186

Sigh. Why do people take an argument and ad absurdum it without trying to understand what is being said and what isn't?

Seriously? Your GPP, titled 'Feel free to move into a cave,' does so little to understand the position of the article, with so much hyperbole, that it's essentially a straw man. Did you try to understand what's being said and what isn't in TFA? Pot, kettle, etc.

Comment Sneaky jab at Common Core (Score 2) 167

FTFS:

the district has been forced to postpone the Common Core-mandated PARCC state exams

But the Common Core DOES NOT mandate any particular exam or evaluation instrument of any kind. PARCC is, according to Wikipedia, "a coalition of 12 states and the District of Columbia that are working to create and deploy a standard set of K-12 assessments in math and English." PARCC is basing their assessments upon the Common Core standards, but it is PARCC that mandates the exams, not Common Core.

Common Core is, literally, just a list of skills that students should have at various grade levels. For example, sixth grade math students are supposed to be able to "Write, read, and evaluate expressions in which letters stand for numbers." That simple statement, and many like it, make up the Common Core. It has nothing to do with mandating exams.

The Common Core standards are freely available on the web, in case you would like to look at them: http://www.corestandards.org/r...

Comment "Over the top" (Score 5, Informative) 155

In case you don't know what "over the top" means in this context, this is from Wikipedia:

In broadcasting, over-the-top content (OTT) refers to delivery of audio, video, and other media over the Internet without the involvement of a multiple-system operator in the control or distribution of the content. (A multiple-system operator or multi-system operator (MSO) is an operator of multiple cable or direct-broadcast satellite television systems.)

So, apparently, it just means streaming media over the Internet.

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