![]() Let’s begin with a discussion about what can and cannot be seen either with an unaided eye, a telescope, or a photographic exposure. But alas, Barnard’s Star is too dim to see with the naked eye, and I do not have a GOTO mount! Let’s explore how else I can point the telescope at an object that is too dim to see and is hidden among so many other stars. A computer-driven GOTO telescope mount can be commanded to drive the telescope to the object’s coordinates, and GOTO capabilities are within reach of amateur astronomers with very modest telescopes. There is also an easy way to find objects that cannot be seen with the naked eye. I simply point the telescope at the object by aiming the telescope’s red dot finder at the object, and the object, which I can clearly see without the telescope, can also be seen within the eyepiece field of view with little if any additional adjustment of the telescope. If I were looking for a bright naked-eye object, such as the Moon, Jupiter, or Saturn, finding it and photographing it would be quite simple. To define the problem, let’s first examine two easy techniques to find a celestial object. This article is about the principles, planning and techniques that I used to find Barnard’s Star. I eventually abandoned the email in favor of this essay-length piece that I could more widely share by posting to my Web site. I started writing a quick response to unboggle (unbottle?) his mind, but the scope of this response soon grew much more involved than I had anticipated. ![]() The reader next tells me that it boggles his mind that I can find a specific star out of all of those billions. I have since written up a description of this object and posted it and the photograph to Jim Johnson’s Astronomy Web site. I did my homework (planning) and managed to get out on a clear night to capture a photograph that included Barnard’s Star. As I will describe later, the reader’s question is not the beginning of my journey to Barnard’s Star. An interesting characteristic of this star is that it has the highest proper motion against the “fixed” background stars of any star that can be observed from Earth. It is a low-mass red dwarf that even at about six light years away is too dim to be seen with the naked eye. In order to account for the closest star that I could photograph, I qualified the question with “visible from my northern hemisphere location” and the star that I seek becomes Barnard’s Star, our fourth closest stellar neighbor after the three stars of the Alpha Centauri system. This star is located sufficiently deep in the southern hemisphere sky that it is perpetually hidden from view at from my northern location of 39° north. Alpha Centuari A, however, is similar to our Sun in size, mass and spectral family, and appears to us as the third-brightest star in all of the Earth’s night sky. A telescope is required to discern the two dimmer components Alpha Centauri B and C. In early October, a Scope Out Next Month reader asked me to “photo the nearest star, and tell us about it.” The Alpha Centauri system of three gravitationally bound stars is actually the our closest stellar neighbor at about four light-years away.
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