January 09, 2006

North Star actually three. Twin suns of Tatooine? Pfft!

Just one of the many amazing things Hubble has discovered. Good thing we're letting it fall into the ocean.

  • Min min min min minnesotaaaa
  • Well, we've actually known it was 3 stars for a very long time, just nobody's been able to snap a picture of the third one until now, because it's so close to the main bright star.
  • Minnesota has had multiple North Stars.
  • **seconds Capt. R's snark**
  • I'll fix the Hubble for $75.
  • The Hubble coming down is so sad.
  • Well, for as little as $75...
  • Look, fixing the hubble is going to cost at least Six Hundred Million Dollars (tm), possibly up to Two Billion Dollars (sm). Don't you people understand priorities? Iraq! Terra! uh . . uh . . Freedom for the brown-skinned peoples of the uh . . east! It's hard! We're not gonna cut and run! Toby Keith, play us offstage! *waves, thumbs up*
  • When you wish upon a staaaaarrrrr....
  • I always love it when we get an "artists conception" of what is supposed to be a photographic discovery. I think this is supposed to be the actual hubble photo (in composite) And from Using a Telescope: Observe double stars Astronomers estimate that 60 percent of all the stars in the Milky Way Galaxy are double or multiple stars. These stars appear as one to the unaided eye, but many may be resolved into pairs with the help of a telescope. I don't think there's an amateur astronomer I know who doesn't enjoy observing double stars. It's fun, easy, rewarding, doesn't take a complicated setup, you can observe from within a city, and challenging objects exist for every size of telescope. In addition to where the double star is in the sky and how bright each component is, there are two quantities with which a double star observer should be familiar. The first is the "separation" of the pair. This number is given in arcseconds, and it is simply the distance between the two stars. The second quantity is the "position angle." This is the angle, measured from north through east, of the fainter of the pair (the "companion," or "secondary") from the brighter (the "primary"). For instance, if the companion is due north of the primary, its position angle is 0°. If it is due east, 90°, and if midway between south and west, 225°. To determine the directions in your field of view, just let the stars drift for a while. If your telescope has a motor drive, turn it off for this check. The stars will enter the field of view from the east and exit to the west. Determine the longest path for the stars you see drifting through the field. This is your east-west line. The north-south line is perpendicular to it, and to find it, turn the drive back on, center a reasonably bright star, release the declination lock on your drive, and move the telescope by hand toward the north. As you observe the field of view, the bright star will be heading out, toward the south. Reverse this if you are located in the Southern Hemisphere. The technique is only slightly more complicated if you own a telescope on an alt-azimuth mount. To move this type of telescope "north," you have to adjust the altitude and azimuth motions simultaneously. The size of your telescope will influence which double stars you observe. The resolution of a telescope only depends on its size. Double star observers often refer to a rule of thumb called "Dawes Limit." The formula for Dawes Limit is r = 4.56/D, where r is the separation (in arcseconds) of the closest resolvable double star, and D is the diameter of the objective in inches. Alternately, you can use r = 114/D, where D is the diameter of the objective in millimeters. And remember, Dawes Limit is only a guideline. One reason for the popularity of double stars is that many of them show color. Colorful double stars are a joy to behold. It does take some time at the telescope before you begin to see colors easily, but the payoff is big. Close double stars often help us see color. The contrast between two or more stars in close proximity brings out subtle color tones that normally would be lost if each was viewed separately. Some of the enjoyment in amateur astronomy is in sharing observations with friends. You will find, however, that color perception at the eyepiece is about as personal and subjective as any phase of our hobby. Colors that you see apply to your eyes, period. Consider the following example. Once, at an observing session, my friend Steve Coe of the Saguaro Astronomy Club of Phoenix, Arizona, mentioned that he saw the double star 107 Aqr as white and light green. His friend Gerry Rattley immediately stepped to the eyepiece and, after a moment, asked, "Which star are you calling green, the orange one?" - - - More than you wanted to know?
  • *runs outside and waves at the sky*