New Mexico Sun Stories

Tee hee. My friend David Beining sent me a link to this image with the subject “Sci Viz New Mexico Style.” It come from a blog entry on Duke City Fix about sunlight reflected off a shaving mirror buring streaks into a wooden wall (a daily event, and the two gaps represent cloudy days). It recollects another New Mexico treasure, the Sun Dagger at Fajada Butte in Chaco Canyon.

As usual, David’s offhand email got me to looking online for, well, something to link to about the Sun Dagger (e.g., the above). I came across the Exploratorium interactive (part of their much larger site about the site), and I have to say that, except for the annoying spinning zia symbol, it’s quite good. The U.C. Berkeley-based Traditions of the Sun also offers a great introduction to the archeoastronomy of Chaco Canyon. We Bay Area folk have Nuevo México down pat!

The Solstice Project interactive model also looks interesting, but I can’t play with it…

Anyway, from shaving mirrors to ancient archaeological sites, the sun plays an important role in our lives. As long as it doesn’t burn our house down, I suppose.

Sunset Sadness

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!


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.

Lunar Transit

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!

All for McNaught

The image above comes from the SOHO “latest image” gallery, which shows the latest pictures from the Solar and Heliospheric Observatory (SOHO). An article on their website describes the passage of Comet C/2006 P1 (McNaught) through the satellite’s field of view.

The comet is passing close enough to the Sun to enter the field of view of the Large Angle and Spectrometric Coronagraph (LASCO), which normally monitors the faint glow of the Sun’s corona. Because the comet shines much more brightly than the tenuous gas flowing outward from the Sun, it appears as a bright, washed-out swath in the upper left of the image. What’s wonderful about the picture is that it’s data, collected in a somewhat clinical, unexciting fashion, that happens to show an unusual, transient phenomenon in our solar system.

Earthbound images of the comet can be found in a gallery of pictures taken from the ground.

More 3D Dangers

I honestly pay little attention to Astronomy Picture of the Day (APOD), but it drew my attention to the image above (describing it as “a just-for-fun 3D presentation of the Mercury transit”). Hmmm.

If you take a look at the original source of the image, you can also find a Flash animation of the image and a “3D orbit” of the same. My issues? Fake stars for a start (in the animated versions of the above image, and admittedly, you want something in the deep background to optimize the dimensionality), although that’s just a pet peeve. Also, creating artificial stereo and labeling it as the ”transit” seems very deceptive to me (why not take two successive images of the transit from the same location on Earth, then create a stereo pair from them, which would reveal more about the underlying phenomena). And the “3D orbit” is utterly bogus and reinforces confusions that many people have about the scale of planets and their orbits.

At least the APOD description made it clear that it’s“just for fun.” Some explanatory text (aside from the sources of the imagery) would be helpful on the source page, too. For example… “Since the 17th Century, observations of planetary transits have allowed astronomers to determine the three-dimensional scale of the solar system—the actual distances between the Sun and planets. This 3D view of Mercury and the Sun pays homage to that achievement, using spacecraft data in lieu of actual terrestrial observations.“ Or something similar.

Honestly, I feel bad about being such a critic, especially since the Sungazer website, which offers scads of gorgeous images of the Sun in various wavelengths. It represents the work of one guy working on his own, and obviously, Greg Piepol is providing a great service to the web community. My kvetching should not be interpreted as any kind of indictment.