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Comment: TFA speaks the truth... DUH! (Score 1) 465

by meetpi (#42493721) Attached to: Death of Printed Books May Have Been Exaggerated

The thing I find amazing is how people (and by people, I mean media/tech pundits) consistently buy into the hype cycle (and by buy into, I mean, write stories that feed it) and then are totally amazed/smug when their most extreme predictions don't eventuate. Stay tuned for the next part of the hype cycle when the self-same pundits who told us that e-books would soon replace ALL printed media begin proclaiming that ebooks are a stillborn technology that nobody really wanted anyway.

Technological innovations are so often presented as either/or propositions: either technology B will completely replace technology A, or technology A will see off the challenge of technology B and live on (and in most cases tech B is going to replace tech A so you'd be better be ready for it, buddy, or else BAD STUFF)

In reality, most times technology A and technology B fall into a relationship with each other that satisfies most people, forming a new hybrid which offers people the best of both worlds. The only time a new technology completely overshadows an existing technology is:

a) when the new technology offers exactly the same thing as the old tech, but also offers up some significant benefit over the old;
b) when the new technology is backed by a power with the ability to distort the market; and,
c) the combination of a and b.

So e-books will co-exist with printed books because there are strengths and weaknesses in each format that the other does not completely account for, and there is not a significant/powerful enough vested interest trying to make one displace the other.

But wait! I coud be wrong. After all, soon MOOCs [or insert other darling tech] will completely replace universities [or insert other established institution/tech/practice].

Comment: Re:Black-and-white? (Score 2) 34

by meetpi (#42436719) Attached to: NASA Releases New Photos of Saturn's Rings and Clouds

Not a dumb question at all, it's actually a very good question. The short answer is that an image taken by a standard digital camera would probably be pretty disappointing.

The first thing to realise is that your eyes aren't really like cameras at all. There's a complex series of interactions in your eyes and brain that take place before you perceive an image. When you take a colour image with a digital camera most people reasonably expect it to match what they see. So, your digital camera manipulates the raw data it gets from its sensors to munge it into a form that looks like what you see. Like the Cassini cameras, a digital camera detects the level of light hitting its sensor and uses different coloured (red, green and blue) filters to turn this back into a colour image. It also often applies various algorithms to the image data to adjust the relative intensities of the light.

The result is an image that's more of less what you see. But there's lots of ways this can fail. Sunsets, for example, are difficult to capture in a way that meets our expectations. If you have an image with a bright area (the sky, say) and a darker area (an area in shadow) it's impossible to get the entire image properly exposed.

When you send a probe a long way from the sun and take photos with a very sensitive camera you get a set of data which you can assemble in lots of different ways, all of which are true representations of the light "seen" by the probe. If NASA attached a typical colour digital camera to the probe they'd just be attaching a much more basic version of the imaging sensors they already have.

So why don't they just process all the RAW images into colour ones? Well, most are pretty dull, and it's not worth the effort. So instead, they make all the raw images available (see them here), which look like a series of black and white images (you can sometimes assemble these into colour images in Photoshop/GIMP). Out of the thousands of images they take only some of them are considered interesting enough to spend some time processing into full colour images.

Comment: Re:Earth-like lights (Score 3, Insightful) 90

by meetpi (#42431209) Attached to: Odds Favor Discovery of Earth-Like Exoplanet in 2013

There are actually a few ways that planets are detected. The dimming of the star as a planet passes in front of it is one method. This only works if the planet passes exactly between us and the star while we're looking. This can only happen is the planetary system is aligned the right way (more or less side-on) to us. It also tends to favour detecting larger planets with fast orbits (an alien looking at our solar system would have to wait one year to see the Earth pass the sun twice, and decades for some of the outer planets).

Another method is to detect the 'wobble' of the star as its planets orbit it. Even though stars are very big and their planets very small, the gravity of planets orbiting a star does pull the parent star around a little, and we can detect that. This tends to favour bigger planets that are orbiting close to the host star as well.

Another is to look for microlensing effects (as an object with a large mass, like a planet, passes in front of a star it can act like a lens, bending the light and causing a brightening effect on background stars). Again, this is biased towards larger planets.

To answer your question, though, in principle, if the planet that's passing in front of the star is very bright it would throw off calculations. However, for it to have enough an an effect to be noticeable it'd have to be very bright, because stars are VERY bright. A planet covered in street lights would still be essentially black when compared to the light emanating from its host star, and eve if it were covered with lava, the lava glow wouldn't make much of a difference, either.

In fact, if you think about it, a really bright planet would be even more detectable. The problem with seeing planets orbiting their stars is that their stars are so bright, the planets get lost in the glare of their star. If a planet was bright enough to throw off the calculations, it might be bright enough to be seen!

Comment: Re:Forget about it. (Score 1) 90

by meetpi (#42431143) Attached to: Odds Favor Discovery of Earth-Like Exoplanet in 2013

And it is interesting that statues made thousands of years ago depict people wearing what looks like spacesuit helmets. Long before Star Trek, so what was the inspiration for that? Weird.

So, out of all the different millions of riffs on a theme of stylised human depicted by thousands of human cultures across the millennia, what are the chances that one later culture would look back at the work of an earlier culture and see something familiar (perhaps mystical) in the depiction?

(the answer is: somewhat less improbable than visitations by a humanoid alien species who are advanced enough to cross space-time, but still wear 1960s-era Earth spacesuits.)

Comment: Stellar obesity (Score 1) 21

by meetpi (#42231653) Attached to: Astronomers Detect and 'Weigh' Very Young Solar System

After weighing the young star system, astronomers have become concerned that young star may be obese. Stellar obesity is becoming an epidemic in the young star population these days, and astronomers are concerned that if something doesn't change soon, bans will need to be introduced on the advertising and possibly the consumption of junk proto-planetary dust and related materials. According to a recent report, stellar obesity costs the nation an estimated 10.3 trillion dollars in medical costs and lost productivity each year.

Comment: A few words of caution (Score 3, Insightful) 174

by meetpi (#42219577) Attached to: Using Multiple Forms of Media At Once Correlates With Depression, Anxiety

Given that I can't afford to pay the publisher's ludicrous $51 for 24 hours access to this paper, I have to glean information about the study from the abstract and summaries.

This study is, at best, a preliminary study. The researchers use a small sample size which they generalise to a large population (they sample 319 people) and they are not using a random sample (they used college undergrads, presumably self-selected). So, basically, what this tells us is that there is some correlation between certain kinds of media use behaviours with *possibly* depressed/anxious undergraduates at Michigan State. It is highly inaccurate statistically speaking to generalise these results to the general population. At best, this study might suggest that there is phenomena here that is worthy of further examination by a proper study.

I'm not criticising the researchers: preliminary studies like this are the first step to getting funding for a more robust study, and they're not claiming anything earth-shattering or being sensationalist. But /. readers need to be aware that this is preliminary research, and does not mean what the headline suggests it does. A better headline would be something like "Preliminary research suggests there may be value in studying the relationship between multiple media use and depression"

On a related note, I wish psychologists would stop using students as guinea pigs and then publishing papers on the results. We already know waaay too much about college undergraduates.

Comment: Exciting times (Score 5, Insightful) 24

by meetpi (#42031509) Attached to: Astronomers Get Picture of Nearby Exoplanet

It is a really exciting time in astronomy at the moment, a real age of discovery. As the article points out, it was not so many years ago that we didn't even know if exoplanets existed, and now we know about nearly 1000 of them. Our detection methods, while clever are pretty limited. They all tend to bias discoveries to certain kinds of planets and star systems, so it's reasonable to expect that the typical star system is a bit different than our current database would suggest.

But what's exciting to me is that our imaging technologies are improving all the time, both through better optics and computer assisted imaging (eg: adaptive optics which can offset much of the distortion caused by the Earth's atmosphere). This means that there's an excellent chance that before long we'll be able to start getting more detail about these systems, possibly including analysis of light from some of the planets which will tell us what kind of gases are in their atmospheres. In my lifetime we may even be able to answer the question of whether life exists on other planets (not necessarily intelligent life, but any life would be a momentous discovery).

All in all, it's a great time to be alive: I think of it as the dawn of an age of discovery. If you're into exoplanet discoveries and you have an iPad, I'd highly recommend the Exoplanet app (I am not affiliated with it in any way, it's just a cool little app).

Comment: Re:13.3 billion in one direction? (Score 5, Informative) 105

by meetpi (#42018173) Attached to: NASA Discovers Most Distant Galaxy In Known Universe

It's also worth pointing out that in the context of the universe, there is no edge. By default we tend to think of the universe as being like an explosion in space where the first particles ejected are at the edge of the explosion radius.

However, when we're discussing the universe, this explosion is actually creating space, so the expansion is not from the core to the edges, it's happening through all of space - everything is moving away from everything else. Think of it like the surface of a balloon that is being blown up. In 2d terms, all points on the surface of the balloon are moving away from each other, but none of them are at the 'edge' of the balloon.

Someone standing on the surface of a sufficiently large balloon would look around and see everything receding from them - it would be reasonable for them to feel they were at the centre of the surface of the balloon and that therefore somewhere there was an 'edge' - but they'd be wrong.

We can defeat gravity. The problem is the paperwork involved.

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