Monthly Archives: March 2007

Purple Rose of Virgo?

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Okay, I liked the Woody Allen film as much as anybody, but why has ESO titled its latest press release “the Purple Rose of Virgo”?

Aside from my lack of comprehension regarding the obscure (I’m not sure I could even call it “pop”) culture reference, I have a gripe with the reference to color. “Purple” is a tricky color, and one that doesn’t occur via blackbody radiation. So it seems inappropriate to describe a galaxy by a color it only possesses because of image manipulation.

In the biz, we call this “color enhanced.” But it should not suggest the actual color of the object, nor should it be used as the basis for a press release title!

Grumble. Time for more coffee.

(Oh, by the way, that’s a supernova below and to the right of the center of the galaxy! Nifty.)

Blurry Binocs

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I apologize for my lack of posts recently. I’ve been terribly distracted—in way I’ll announce soon enough—and the blog has languished. For which I apologize. We’ll see if I can get back in my groove!

A quickie for today. I just ran across the fantastic Journal of Vision: “a scientific periodical devoted to all aspects of visual function in humans and other organisms,” published for free online in a format that “encourages the effective use of color, multimedia, hyperlinks, program code, and other digital enhancements.” Hours of fun! This is great stuff.

The image above comes from an article about how contrast differences affect binocular vision. (BTW, a “saccade” is a rapid movement of the eye; that will help you decipher a good part of the article.) A little on the technical side, but the kind of information that might be helpful when designing content for, say, a stereo display.

There’s more to come! Just a teaser while I get back in the swing of things…

Poisoned Intution

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The above image comes from a NASA multimedia piece released the other day. Although the caption doesn’t say so, I’m 99% sure that’s exaggerated terrain. It would be nice if the caption indicated that.

This actually qualifies as one of my “Planetarium Pet Peeves” and thus requires little further complaint on my part. I’ll quote two of my colleagues on the topic, even though their words also appear on the “pet peeves” page…

As Chris Anderson puts it, “When we fly audiences over a vertically exaggerated landscape, we poison their intuition about the way these worlds would actually appear.” Or, as my colleague Carter Emmart has been known to observe, “even Iowa looks mountainous when you exaggerate its terrain by a factor of ten.”

Sunset Sadness

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The above image is circulating via email accompanied by the following message:

“A scene you will probably never get to see, so take a moment and enjoy God at work at the North Pole. This is the sunset at the North Pole with the moon at its closest point. And, you also see the sun below the moon. An amazing photo and not one easily duplicated. You may want to pass it on to others.

“The Chinese have a saying that goes something like this:

“ ‘When someone shares with you something of value, you have an obligation to share it with others!’ ”

First of all, allow me to assure you that you have no obligation to pass this along to anybody! It’s not what it purports to be. And why do we always attribute sayings to the Chinese? I recently kvetched to some colleagues about the “picture is worth a thousand words” saying being so described, when in fact, it’s due to Fred Barnard, an American advertising manager in the 1920s. Anyway, anyway, anyway,…

This picture is not from the North Pole; it’s computer generated. How can I tell? (Aside from the tell-tale fakeness of the image?) First, the sun and moon are basically the same size as observed from Earth, so you would never see a giant moon like the one above. Also, because of Earth’s tilt, a crescent moon can never appear directly above a setting sun at the North Pole.

This isn’t “God at work”! This is Bryce 3D!

Sigh.

I keep starting to write annoyed and disparaging things, but perhaps I should just go to bed. Just, please, don’t forward this image to anybody. Ever.

Of Nebulae and Drawings

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I noticed a slight error that seems to be floating around out there on the net. Several “this day in history” sites, including the Wikipedia page on 4 March list today as the “first sighting of Orion Nebula by William Herschel” in 1774. Strictly speaking that’s not untrue—Herschel seems to have made his first observations of the Orion Nebula on 4 March 1774, but in fact, telescope observations of the nebula had originally been described by Peiresc back in 1610 (cf. a lengthy list of early observations of deep-sky objects).

What’s important about Herschel observing Orion is that it got him started on a massive cataloging campaign that resulted in a list of thousands of deep-sky objects. And a numbering system that’s still in use today!

All this thinking about the Orion Nebula reminded me of the image shown above—a sketch by William Herschel’s son John. I link to a fine-art print offered by David Malin of the same, and in a continuing cascade of connections, I also wanted to point out a marvellous essay by Malin in which he compares Herschel the Younger’s drawing to (a somewhat more psychedelic) one created by William Parsons. As he points out, differences between the two images “result not from changes in the nebula or in telescopic power, but from subjective differences in the way their creators saw, remembered, and sketched what was essentially the same subject.” I’ve blogged about related issues before, but Mailin is both nicer and more eloquent than I.

Anyway, I hope you appreciate a random stroll down this-day-in-history lane.

Lunar Transit

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NASA’s Solar TErrestrial RElations Observatory (STEREO) mission released a spiffy video of the Moon transiting the Sun. I find myself oddly captivated by the video, watching it over and over…

It reminds me of the good ol’ days of the SGI Reality Centers, when managing high-resolution data was a bigger deal than it is today. They would loop TRACE imagery of the Sun. I think I could watch it for hours, although I never really had the chance. And when we tested audiences for our Cosmic Collisions space show, it seemed I wasn’t alone, since people responded most positively to the solar images.

At the same time, I kind of dislike the color. It seems garish, even though I know it’s done in the standard mappping style. Heck, the web page even tells us: “The Sun as it appears in these the images and each frame of the movie is a composite of nearly simultaneous images in four different wavelengths of extreme ultraviolet light that were separated into color channels and then recombined with some level of transparency for each.” Except for the “some level of transparency” bit, that’s a fairly lucid explanation.

More lucid than this post, I suppose. But you should watch the movie!

Spheres in a Plane

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Yeah, I remember those long nights at my college paper (The Cornell Daily Sun, if you’re curious) when we’d be laying out a page and recognize the need for a photo to fill space and look pretty and make the design more appealing. And, well, sometimes the photo we’d choose would be, um, kind of a stretch.

Kinda like the image above.

It accompanies a press release on computer simulations of atomic processes in nanomaterials, accompanied by a delightfully mystifying caption: “This three-dimensional atomic simulation shows the absorption of a line defect (caused by an impinging screw) by an existing twin boundary (green spheres) in nano-twinned copper.”

Um, huh? Does that mean anything? I honestly think that someone at MIT decided they needed a picture to go with the text, even if it’s meaningless. Twin boundary? It’s explained as “an abrupt internal interface each side of which is a precise mirror reflection of atoms of the other side” in the press release. But how is that shown as spheres exactly? Anyway, problem piles atop problem, leaving a lack of clarity in its wake.