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San Jose Astronomical Association Membership Form Fremont Peak observatory gets a facelift SJAA activities calendar Morris Jones and Mike Koop Jim Van Nuland February Mike Koop took these pictures of lighting and power, and a large outdoor 1 Deep sky weekend. Sunset 5:31 the nearly completed improvements multi-use area on the west side. p.m., 1% Moon sets 5:54 p.m. made by State Parks at the site of the 7 Houge Park star party. Sunset Fremont Peak observatory as part of 5:39 p.m., 38% Moon sets 11:52 their volunteer improvement program. p.m. Perhaps the most significant 8 ATM class. Houge Park, 7:30 improvement is the removal of four large p.m. trees that obscured the southern sky 15 General meeting, Houge Park. from the once popular observing area 8:00 p.m. SJAA flies through the behind the ranger residence. Other Leonids. Mike Koop, Morris and improvements include new roads and Jane Houston Jones Elections! walkways with low-intensity safety 20 ATM class. Houge Park, 7:30 lighting, observing pads on the south p.m. side of the observatory with safety 21 Astronomy class. Houge Park, 7:30 p.m., Jay Freeman, Binocu- lar observing 21 Houge Park star party. Sunset 5:54 p.m., 67% Moon rises 11:41 p.m. 22 Deep sky weekend. Sunset 5:53 p.m., 56% Moon rises 12:50 a.m. March Top right: The before picture, Fremont Peak Observatory as seen from Fremont Peak. Above 1 Deep sky weekend. Sunset 6:00 left: Powered observing pads. Above right: Multi-use area with turnaround for constellation talks p.m., 1% Moon rises 6:49 a.m. and additional telescopes. Below: The after picture, Fremont Peak Observatory as seen from the 7 Astronomy class. Houge Park, summit. Note that the large tree seen in the top right picture is no longer there. 7:30 p.m. Dave on the Moon 7 Houge Park star party. Sunset 6:07 p.m., 22% Moon sets 10:40 p.m. 8 ATM class. Houge Park, 7:30 p.m. 15 General Meeting, Houge Park. Robert Naeye, ASP: Solving the Universe’s Mysteries Through Extra Dimensions 22 Deep sky weekend. Sunset 6:19 p.m., 71% Moon rises 11:50 p.m. 27 ATM class. Houge Park, 7:30 p.m. 28 Houge Park star party. Sunset 6:27 p.m., 12% Moon rises 4:54 a.m. 29 Deep sky weekend. Sunset 6:26 24 Hour News and Information Hotline: (408) 559-1221 p.m., 7% Moon rises 5:20 a.m. http://www.sjaa.net Copyright © 2003 San Jose Astronomical Association, Inc. Volume 14 Number 2 Official Publication of the San Jose Astronomical Association, February 2003 Mooning you’re not going to worry much about eye relief. Even standard plossls will Simplified eyepiece selection deliver just fine. Dave North Enough blah blah. What’s the bottom line? This month’s question wandered It means we’re ready to mention Based on experience, you want a in via email from member George Feliz, another point: eyepieces don’t look at 7mm Nagler. who is curious about choosing eye- the Moon without a telescope. Really. pieces for mooning. If you have an 80mm refractor or a It’s the eyepiece I use the most, Complicated question, as he was 4.5-inch newt,2 eyepieces are not going was once popular with Rich also curious about mounts, floaters, to be overly important. You won’t be Neuschafer, and is still almost the and whether I agreed with a planetary/ able to get much above 180x or so, and exclusive favorite of Craig Wandke. All lunar eyepiece review at that will usually be fairly steady. The of us have something of a reputation as cloudynights.com. So let’s dive in. image will be somewhat dim, so there lunar observers, so. First a ground rule: I’m only going won’t be a lot of detail to distinguish. Now ask any of us, and we’ll tell to talk about lunar viewing. That’s what This will also go for the 5" you it won’t give you the very finest we’re here for. catadioptrics.3 contrast. It might have internal reflec- And for that reason, the above If you have a 4-inch refractor or a tions under some conditions. It might URL is not particularly useful.1 But: it is six inch newt or Mak, you’re in the have a bit of a soft image compared to instructive to consider why, even if the “medium” ballpark where you can get the very best eyepieces. discussion breaks my first ground rule. So why do we like it? It’s close in Why? Because there is not a all categories, has reasonable eye great deal of overlap between planetary “Wait, Dave. You threw out relief, and has a wonderful wide field of and lunar observation, and they try to view, which gives you “context” and “an cover both in one article. all this technical crap and attractive field.” The object of most planetary then said something like Does it give you the best “data?” observation is the distinction of fine that? Are you nuts?” Nope. shades of color (often similar colors!) So, in your next incarnation as a with soft edges. This can be seen computer, stay away from Naglers. In especially when you consider the two into the 225x range fairly well, and this life, take a look through one and “tough” planets, Jupiter and Mars. maybe push 300x at times (though see what you think. Really seeing what’s going on you’re again getting a dim, uncontrasty Wait, Dave. You threw out all this requires an extremely fine revelation of image). technical crap and then said something contrast and color. Over that, you’re in Fat City and like that? Are you nuts? Enough of planets. you’ll need some fairly good eyepieces Maybe. On the other hand, the On the Moon, most demands for to get the very best out of your scope. idea here is to look at the Moon and contrast nearly disappear. There is no More blah blah. Now what does it have some fun. Enjoy. atmosphere to “smudge” the light. mean? For a lot of folks, trading obtuse There are no clouds. There is almost no It means yet another problem: theories is the fun of astronomy. For color and it seldom comes into play. focal length. The longer the focal length others, it’s playing with hardware. For It’s basically a problem of seeing and the longer the f/ratio, the better. others, it’s looking at stuff. For most of medium gray contrasted against a Just take my word for it. us, it’s some combination of those really hard black, with some whitish Long focal length, though, means things. elements thrown in. The range of I have noticed, however, that the contrast from the lighter portions of the folks that enjoy looking at stuff often Moon to the incredible black of a lunar 2 I have a 4.5-inch newt on which I have break with acknowledged theory, even shadow is about as sharp as it gets lavished an extraordinary amount of effort, just when they agree with it. to see how nice it could get. The answer? short of stellar observation (I love 225x and a resolved core of M13 is easy from Some examples: double stars!) a dark site. When you hear these can’t be Jay Freeman claims aperture Another point: we get a Lot of useful instruments, be very dubious. wins, flat out (I agree mostly) and light from the Moon. It’s very bright. 3 I have a C8, and have heard all the theoretical proceeds to observe with smaller crapola about how the huge central obstruction Blah blah. What does it mean? kills the contrast. In the real world, though, it instruments. gives excellent images and has severely Rich agrees a good newt of trounced my 5-inch Tak under the right greater aperture will deliver more data conditions, even on (gasp!) planets. Contrast is 1 Okay, I didn’t insert the URL because I think a than a smaller refractor, and proceeds similar, but eight inches of resolution still fair amount of the article is more likely to whomp on five. It doesn’t give quite the pretty to enjoy the wonderful views through his mislead than educate. So I don’t endorse it, image, though. Oh, come on, Dave. Who cares even if I strongly agree with some of it. from pretty? Continued on next page SJAA EPHEMERIS Page 2 February 2003 Mooning I do not necessarily think my Continued from previous page selections are the best for anyone else. I definitely do not like Televue Radians, refractor almost exclusively. for example, and they have been quite See a pattern? popular. I consider them soft, twitchy In my case, I know the best views and full of reflections. of the Moon and planets have come I don’t like the cheapo orthos I’ve through my 12.5-inch newt with seen, though they do get good reviews Takahashi eyepieces, so most of the from other folks. time I look at it through a five-inch I do like a lot of eye relief, espe- refractor and a Nagler. cially in the winter when the mist from Why? my warm eye can fog the eyepiece. Partly because most nights, the But here’s the real point: there’s seeing isn’t that great.
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