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RE:Creation
The Yale Bright Star Map ... provides more stars
than The Night Sky in Winter There's no question. Winters in Vermont may be long and, often, harsh. They are, in some respects -- insofar as they require something of endurance and, often enough, ingenuity -- a test of character. But there is something that comes with the deep, dark and long nights that may provide a different kind of revelation ...
If you've ever been out to view the night sky in winter, you know what we're talking about. Particularly around the dark of the moon, and preferably near or after mid-night, on a clear night, the sky is the deepest sort of black velvet. ... The Naked Eye View: If you give your eyes the time, gradually, more and more stars become visible. Depending on what sort of light conditions you just came from, it can take as much as five minutes or more for your pupils to dilate fully -- as they must in order to see some of the dimmer stars. But it's worth the time, even in the colder weather. It seems, in fact, as if the cosmos is giving birth to stars while you're watching. ... Of course, no matter how much your eyes adjust, you can never see all of what's out there. That's one of the reasons things like NASA and the Hubble Telescope exist. ... Images of Deeper Space: The Yale Bright Star Map, from the Tycho Star Catalog {shown above}, shows more than 9,000 stars. {You can click on it, or any of the other images, for a larger version.} But it is one of the lower resolution images of what's out there. ... If you look closely, you can faintly see the bell-shaped curve of clustered stars, more readily visible on the descending right side.
The next highest resolution is provided by the Hipparcos Star Map, from the catalog of the same name. It shows some 118,000 stars. ... Notice that, with the addition of more stars, the bell-shaped curve -- beginning at the lower left -- becomes more discernible. ... But if one really wants to get a sense of that curve, then the best option is the Tycho Star Map. ... With more than 1 million stars, the Tycho Map, from which the catalog derives its name, provides the best image to show that the cosmos -- however much it may be expanding and, therefore, becoming less dense -- is, nonetheless, filled with light. ...
. Here, the bell-shaped curve is distinct ... ... as is the fact there's scarcely a point in space not punctuated with light if one looks deeply enough ... and, of course, with the proper equipment. . The Pleiades is a favorite constellation around here. ... A small cluster of what appears, with the naked eye anyway, to be about a dozen small stars, the Pleiades is small enough at these distances so that some or all of it can actually disappear from view if you look directly at it. That, of course, is due to the 'blind spot' on the retina -- a small section which lacks the photoreceptors for the perception of black-white contrasts [rods]. The Pleiades seem to fit almost perfectly into the blind spot of the retina. ... This next photo -- a product of the Hubble Telescope -- is of an interstellar cloud [IC 349] within the Pleiades constellation. ...
The cloud is a composite of cold gas and dust particles, and is actually, in itself, black. The light illuminating it comes from one of the Pleiades' brightest stars, Merope, whose reflection is visible, including lens refractions, in the upper right corner. Such a phenomenon is referred to as a reflection nebula. ... While the streams of light from Merope are a product of the optical element of the lens, the streaks emanating from the cloud toward the star are, in fact, the real thing. ... According to the Space Telescope Science Institute [STSI] -- jointly operated by NASA and AURA [the Assoc. of Universities for Research in Astronomy], the phenomenon, captured for the first time through the Hubble telescope, is the result of what's know as "radiation pressure."
A naked-eye view of the stars can never provide this kind of detail. And, as much as the images obtained provide often-startling pictures of awesome beauty, they are even more valuable for the information they yield about the nature of the cosmos. ... But neither is viewing the heavens through a telescope any substitute for a naked-eye view, particularly on one of the deep, dark winter nights we spoke of at the beginning of this article. So, turn off the lights, dress warm, and wade out into the night. If you give yourself enough time and then look closely, you'll be able to see the Pleiades, Merope among them. If you like, you can even contemplate on the fate that awaits Interstellar Cloud 349 ... or your own. . ******* ******* If you would like to submit something for our RE:Creation feature, or if you simply would like to suggest something you think we ought to cover, e-mail us at ... sports@downstreetmagazine.com. ******* ******* If you would like to advertise in this section, or throughout the magazine, please visit our Advertising Info Pages ... or call, write, or e-mail ads@downstreetmagazine.com. ******* *******
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