Tuesday, February 05, 2008

Polaris In The News And Out

Normally, when I decide what to post here I look for something that is more or less on topic (the Goblin Universe), something that’s interesting to me and something that I figure might be interesting to random people clicking-in from the blogosphere.

Sometimes, however, if an odd topic stays in my mind for a day or two, even if I can’t think of a good reason to post it, I’ll put it up anyway because I figure there might be some kind of subconscious hook that’s important to me even if I can’t put my conscious finger on it.

Today is one of those days.

And next week, I think, is going to be a big, five-day theme week anyway ( gee, I wonder what next week’s topic will be? ), so this week is a good time to get miscellaneous, one-day posts out of the way . . .

Polaris In the News

NASA Launching Beatles Tune Into Space

WASHINGTON (AP) — The Beatles are about to become radio stars in a whole new way.

NASA on Monday will broadcast the Beatles' song "Across the Universe" across the galaxy to Polaris, the North Star.

This first-ever beaming of a radio song by the space agency directly into deep space is nostalgia-driven. It celebrates the 40th anniversary of the song, the 45th anniversary of NASA's Deep Space Network, which communicates with its distant probes, and the 50th anniversary of NASA.

"Send my love to the aliens," Paul McCartney told NASA through a Beatles historian. "All the best, Paul."

The song, written by McCartney and John Lennon, may have a ticket to ride and will be flying at the speed of light. But it will take 431 years along a long and winding road to reach its final destination. That's because Polaris is 2.5 quadrillion miles away.

NASA loaded an MP3 of the song, just under four minutes in its original version, and will transmit it digitally at 7 p.m. EST Monday from its giant antenna in Madrid, Spain. But if you wanted to hear it on Polaris, you would need an antenna and a receiver to convert it back to music, the same way people receive satellite television.

The idea came from Martin Lewis, a Los Angeles-based Beatles historian, who then got permission from McCartney, Yoko Ono and the two companies that own the rights to Beatles' music. One of those companies, Apple, was happy to approve the idea because is "always looking for new markets," Lewis said.

Polaris Out of the News

When I first read that story last week, I just kind of shrugged. It’s the kind of silly-ass (although relatively inoffensive) public-relations stuff administrators of science agencies come up with now and then.

But I found the choice of Polaris interesting. And, although if stars were celebrities Polaris wouldn’t be a hot-button, television-type celebrity star, I found myself thinking about Polaris, thinking about little things to say and I decided I had enough little rambling things to say about Polaris to make a post.


Polaris is an odd choice to grab the world’s attention with a Beatles song because the Beatles are a world-wide phenomenon and Polaris is a northern hemisphere star. Half the planet—everyone south of the equator—never sees Polaris. Why the heck didn’t the public relations people pick a star from the Zodiac that can be seen both north and south of the equator?


Polaris is a second magnitude star. The brightness of a star is measured on a scale where the lower the number, the brighter the star. Polaris is not a very bright star. People living near New York or Los Angeles may never have seen Polaris just because urban skies have become so bright.


Polaris is in a relatively obscure constellation in a relatively empty area of the sky. Most people can recognize the asterism of the Big Dipper in the constellation of the Ursa Major. [An ‘asterism’ is a group of stars that appears to form an interesting pattern of some kind but isn’t in itself a complete, official constellation.] Many people can recognize the asterism of the Northern Cross in the constellation of Cygnus the Swan. Some people can recognize the big W-shape of Cassiopia. But in the middle of these three rather easy-to-see sights, the Little Dipper in Ursa Minor is composed of all dim stars and none of them are particularly close to the easy-to-see constellations. Even if you know the trick of sighting through the two stars of the Big Dipper’s cup it can still be difficult to find the Little Dipper.


Okay. Those are the dubious things about Polaris. Polaris has some cool things associated with it, too. It’s not a Britney Spears celebrity type star so I’m not sure I would have picked Polaris to get world-wide publicity. But for people who are interested in astronomy, Polaris can be a very cool star indeed.


Polaris is not bright, but it is unique in the heavens because it is the northern pole star. It doesn’t move. All the other stars circle around Polaris, but Polaris always stays in one place, every night, all night. That’s a convenient lie, of course. Polaris is actually about half a degree away from the exact northern celestial pole so if you calibrate your telescope mount by sighting on Polaris you have to use a special grid to offset you polar axis by about half a degree. Polaris moves, but it’s only a very small amount.


Because Polaris doesn’t move—for most practical reasons—if you are ever lost and you’re deep enough into astronomy that you can find Polaris you can use Polaris to determine true North.


These are GPS days where little handheld devices tell you your latitude and longitude, but if you can find Polaris and you have a sextant you can determine your latitude the cool, old fashioned way—the way sailors have for hundreds of years—by measuring the angle from the horizon up to Polaris.


I saved my favorite thing about Polaris for last because it touches on a bigger topic that’s important to me, a topic I’ve written about before and I’ll be writing about in the future.

In Saturn and Titan, And The Pleiades I wrote about how the mainstream media and even general astronomy magazines like to publish spectacular, dazzling astronomical images—photos captured with giant telescopes and involving very long time exposures—even though such sights can never be seen with the naked eye. Such photos are beautiful, but when people look through a real telescope and see things that look nothing like the time exposure photographs, some people are profoundly disappointed.

It’s always bugged me that the media creates this totally bogus image of what the heavens look like because the actual beauty of the heavens is more subtle, less dazzling, but every bit as real. Even more real because when people are exposed to the actual beauty of the heavens, even without the dazzling eye-candy, many people become hooked for life on the reality of astronomy.

Polaris is a case in point.

Right next to Polaris there is a tiny asterism, a little semi-circle of about a half dozen very dim stars. They are all about 8th or 9th magnitude so you can’t see them with the naked eye. But with a decent pair of binoculars or a low power, rich field telescope you can see them easily.

Polaris and the semi-circle of stars are called the Engagement Ring. It’s very beautiful in a real, not dazzling sort of way. (It can be hard to see. With mediocre binoculars the Engagement Ring appears small and dim, hardly interesting. With a telescope, the field of view is often too narrow to see Polaris and the others stars all in one view. You need decent binoculars or a regular telescope at low power or, best of all, a good rich field telescope.)

Polaris looks bright compared to the semi-circle of very dim stars and Polaris is set off just a tad from the circle described by the stars so it actually looks like the dim stars form a ring and Polaris is the glittering gem mounted on the rim of the ring.

It’s not spectacular like the glittering blue-white nebulosity you see in time exposure photographs of the Pleiades. It’s not spectacular like the glittering red, blue and white you see in time exposure photographs of the Orion Nebula.

But it’s real and when you actually see it is captivating.

It is, kind of, like a miniature version of the constellation Corona Borealis. That’s the ‘Northern Crown,’ and although it has no spectacular stars or dazzling nebulosity, it actually does kind of look like crown of jewels. When you actually see it, it is beautiful.

I’ve never been sure why the media—and even many astronomers—aren’t satisfied with the real beauty of the heavens. Things like the Engagement Ring and Corona Borealis are so beautiful that even if I go outside to observe something else, I always check in with them and sort of catch my breath knowing that such beauty is out there, up in the sky, free, every night.

Someday, if I ever have a good rich field telescope, I’d like to do a whole series of posts (or, publishers willing, even a whole book) of photographs of beautiful astronomical sights, but I’d take the photographs very carefully to reproduce not spectacular, dazzling special effects scenes, but rather the actual beauty of the heavens as seen by a real human eye in real time.

I’m guessing mainstream publishers would have no use for such a book, but blogs are made for such idiosyncratic content. If I ever get the resources to work on such a project it will be high up on my to-do list.

No comments: