June 2008 - Utah-Astronomy - mailman.xmission.com

Re: [Utah-astronomy] Saturday night at the Gravel Quarry
by Canopus56 08 Jun '08

08 Jun '08

Bob wrote: <snip> > German Platero and myself were left. German had > just learned to use his Bino-viewer with a lot of > help from Kurt Fisher and was having fun with it > on his 12" Meade Cat. German's difficulty was that when a f6.3 focal reducer is placed in an f/8-9 SCT, the generous range of back focus - for which SCT's are well known - decreases proportionately. With the focal reducer in place, the maximum back focus range could not be raised to the level of focal plane of a right-angle with binoviewer. Removing the focal reducer restored the SCT's default longer back focus range and then the binoviewer worked fine. I did not take a precise measurement, but guesstimate that with the 6.3 focal reducer in the place, the backfocus was limited to less than 120mm. Lesson learned: For those of you interested in buying a binoviewer for use with an SCT, be aware of this limitation. As far as the performance of binoviewer, I had a chance to compare M27 in Lowell's SCT with and without an O filter with German's SCT equipped with no filter and the binoviewer. The distinction between the two is the binoviewer splits the light in half but spreads it across two human wet-ware retinal detectors inside of just one organic "ccd" chip. The magnifications were not the same, but my impression was that the binoviewer without contrast filter met or exceeded the single eyepiece filter combination in terms of detectable visible contrast detail. > After 12:30, as everyone else left, as predicted by > the Clear Sky Clock, we were treated a moonless crystal clear sky > and a blazing Milky way and spent another two hours with > spectacular views of numerous deep sky favorites. After leaving at midnight and driving back to Salt Lake, as is my usual practice, I stopped at Little Mountain pass to give the current sky condition one last peek with binoculars. On stopping, I saw the same, clear, cloudless sky with good seeing that Bob described. M7 (Ptolemy's cluster), M6, M8 (Lagoon) and M24 (Small Sagittarius Star Cluster) were all naked-eye objects. Milky Way light cloud regions could be seen from Sagittarius through Cepheus. Theta-Rho Oph dark lanes could not be seen - too close to SLC light pollution gradient. Sky orientiation was typical for early July with the Milky Way spinward arm at 40 degs alt to the eastern horizon. Essentially, it was like a Unita class sky for seeing and transparency, reduced in contrast by SLC light pollution. The air was cold and still - I could easily see my breath during normal breathing. Pulling out 10x50 binos I was able to quickly tick off the basic Messier summer objects: the globs M10 and M14 in Oph; M22, M24, M17 in Sagittartius; M11,the Scutum Star Cloud and M27 and the Coathanger asterism in Sge; split Alberio; M29 in Cyg; the some of the outline of NGC7000 and Harrington 14 in Cyg; M52 in Cep; the Herschel's Garnet star in Cep - which was looking particularly garent that night; and ending with splitting the cat's eye wide double Drac 16-17. Really a quite amazing half-hour. Then I drove home (20 minutes), got out of the car and looked up to find the next incoming band of mid-altitude clouds directly overhead covering 20 percent of the sky. Lesson learned: This year may be "eastern" or "midwest" style observing. The opportunities will be in the leeward side of passing cloud fronts and last an hour or two. Plan to set up, read a book for a while until a cloud band passes, the sky opens up and "magic time" begins. - Kurt

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McCain and Mars exploration
by Patrick Wiggins 08 Jun '08

08 Jun '08

Boy, first he says he wants to overturn Roe v Wade and I say I'll never vote for him and now he says this: http://www.breitbart.com/article.php?id=080606111510.5jnz56gu&show_article=1 Talk about mixed emotions... patrick

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STS/ISS tomorrow (maybe Monday)
by Patrick Wiggins 08 Jun '08

08 Jun '08

Tomorrow (Saturday) the entire state will see the docked pair appear low in the northwest at about 10:13 p.m., reach their highest point in the southwestern sky about 10:16 and fade from view low in the south to southeast about 10:17. While times remain pretty much the same statewide, one's location will determine how close the station and shuttle will appear to come to the Moon and how high in the sky they will reach. Observers in northern Utah will see the duo first pass very close to (and possibly even transit) the Moon and then climb to a point about 1/3 of the way up the sky. Central Utah will see them further from the Moon and just over half way up the sky. Those in the southern part of the state will see them even further from the Moon but virtually straight overhead. There will be an additional pass over Utah Monday evening, the 9th, between 9:22 and 9:28. Positions in the sky will be the same as tomorrow's pass. Even the nearness to the Moon will be similar. But it all happens less than 30 minutes after sunset and with the sky so bright I'm guessing not many will be able to see it. patrick

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Re: [Utah-astronomy] Radio Shack neon lights
by Canopus56 08 Jun '08

08 Jun '08

> On another note, placing the lamp behind a slit will work well > provided that the slit is at the telescopes focal point (infinity). Thanks, Jerry. It looks like I'll have to rethink my plan of whether a light source behind a slit and held in front of the telescope objective will give useable calibration lines for a slitless stellar grating. But, I think I'll still work on the idea and at least give it a mock-up test on a telescope, if only for the hobby entertainment value. Even if I have go to a "slit" spectrograph, a small portable hobby calibration source would be helpful to have, rather than a bulky cold flourescent light. > Regardless of which neon light you get from Radio Shack, you will > need to remove any colored lens over the bulb. Otherwise > the full neon spectrum will not be usable. I bought several of these yesterday, but saw no way to remove the housing covering without the bulb. In a prior post, Chuck and Jerry wrote: > Jerry, for convenience, how about one of those small house-current > continuity testers? They typically have a neon bulb, and a > lamp cord coud be spliced onto the contact leads. Yesterday, I bought packets of red, yellow and green neon mini-bulbs (120 VAC, 3mA) from Radio Shack and a $5 "Extech" neon bulb household current tester at Sears. Turns out the Radio Shack bulbs can be directly connected to AC household current without modification and they will work. Appropriate precautions to assure against accidental electrocution where taken during testing. Testing each one in turn with and without a slit and a hand-held student ProjectStar spectrometer, the results where: 1) green neon - makes a strong yellow line at 5800 and a series of red lines between 6000 to 6100 Angstroms. Also produces an distracting continuous spectrum between 4000-5700 A. Dimmest of the three RadioShack bulbs. 2) red neon - slightly brighter - makes the emmission lines as with the green neon plus a dim blue line at 5300 A. 3) Ektech household current tester - pinkish colored - makes two distinct lines - blue at 5300, yellow at 5800 and the series of red lines between 6000-6100 A. Makes the sharpest lines without a slit. Unclear if the bulb can be removed from the housing without destroying the unit. Plastic housing is incompatible with use in an electronics project box. 4) yellow neon - significantly brightest of the three bulbs - makes two distinct lines - blue at 5300, yellow at 5800 and the series of red lines between 6000-6100 A. Lines less defined than the Extech. This was the clear winner. The Radio Shack yellow neon bulb is embedded in a plastic housing that attaches to project boxes by two hexagonal nuts on either side of a project box wall. This suggests a physical set up of 7 bulbs - 1 in the center surrounded by 6 bulbs - that are banked in three toggle switches. 1st switch - 1 bulb, 2nd switch - add 3 bulbs for a total of 4, 3rd switch - add 3 bulbs for a total of 7. I have bought six yellow bulbs and the other misc parts and will let you know how it works out. Thanks for the help. - Kurt

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Radio Shack neon lights
by Jerry Foote 07 Jun '08

07 Jun '08

Hi Kurt, Regardless of which neon light you get from Radio Shack, you will need to remove any colored lens over the bulb. Otherwise the full neon spectrum will not be usable. To see what spectral lines Neon will produce take a look at the table near the bottom of this link: http://www.newport.com/file_store/PDFs/tempPDFs/e5395_Oriel-Pencil-Style-Cal ibration-Lamps.pdf It is a pretty broad list. On another note, placing the lamp behind a slit will work well provided that the slit is at the telescopes focal point (infinity). Perhaps placing the neon bulb on Patrick's house will make it stellar like from SPOC <g>. I'm not sure of the line of sight here. Using a diffraction grating at the eyepiece will require that the calibration source is similar to the stars. If you place it close to the telescope it will not be stellar but merely flood the entire aperture with the light and thus you won't see any lines. A thought here: perhaps reflecting the neon light image off a small white Christmas tree ornament some distance away from the telescope but not at infinity would work. I remember figuring a mirror with John Dobson we used the Sun's glint from such a bulb about 300 feet away worked pretty well as a point source. It did have a small amount of spherical aberration but we were able to get it pretty close. Maybe Brent Watson could comment on this. Jerry Foote ScopeCraft, Inc. 4175 E. Red Cliffs Dr. Kanab, UT 84741 435-216-5450 jfoote(a)scopecraft.com

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Joe lucked out
by Patrick Wiggins 07 Jun '08

07 Jun '08

Looks like Joe picked a good time to retire from the D News: http://deseretnews.com/article/1,5143,700232169,00.html Joe, BTW, says he's finished with writing articles professionally. However, he says he's willing to write a piece or two for Nova. Any suggestions for what "SLAS specific" things Joe could write about? patrick

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Re: [Utah-astronomy] RE spectrometer links
by Canopus56 07 Jun '08

07 Jun '08

Jerry and Chuck, While I'm going to buy all three of the Radio Shack neon LEDs (red, green and yellow) and check out which is best, do you have any suggestions. - Kurt

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Re: [Utah-astronomy] STS/ISS tomorrow (maybe Monday)
by Canopus56 07 Jun '08

07 Jun '08

Tonight's 10:12pm passage will be a good opportunity for a wide angle photo capturing the ISS track, the Moon and Mars in one 3 deg angle. For GOTO camera pointing purposes from Salt Lake City, near its closest approach, the ISS will pass nearly over 8 mag star HD79726 (SAO 98464) and celestial south of the Moon. HD79276 is about 50' southsoutheast of mag 5.3 bright star pi2 Cnc. Mars at 1.5mags is 2 degs north of the Moon and about three degrees celestial north of the closest ISS path approach. As usual for such photos, exposure balancing a -3.3, -8.7 and 1.5 mag objects will be difficult and a second properly balanced exposure of the Moon quickly after the ISS passes with Photoshop post processing to merge the two images is probably the best bet. ISS passage data: 2008-06-07 22h15m25s MDT ISS Appears 22h10m39s 2.7mag az:299.4° WNW horizon Culmination 22h15m25s -3.3mag az:222.7° SW h:34.2° distance: 583.2km height above Earth: 346.5km elevation of sun: -12° Disappears 22h16m54s -3.0mag az:168.8° S h:19.8° A closest approach ISS to the Moon will be at approximately JEDate 09 16 23 +13 59 13 or a distance of about 1.1 degrees. Moon az and alt J2000 RA:9h17m33.74s DE:+15°15'53.6" JEDate RA:9h18m01.68s DE:+15°13'45.2" Mag -8.7 Azimuth :+268°16' Altitude :+25°45' Mars position: J2000 RA: 9h16m12.05s DE:+17°19'14.3" Date RA: 9h16m40.28s DE:+17°17'06.5" Mag 1.5 Azimuth :+270°18' Altitude :+26°45' The lunar transit centerline ground track runs across a relatively inaccessible portion of Utah. It runs from the northeast corner of Nevada into the northwest corner of Utah about 4 miles south of Grouse Creek, Utah at Lon: 113°54m26s W Lat: +41°38m05s, about 12 miles north along a dirt road going north from state highway 30 near the Lucin turnoff. (Not that I'm going. -:)). - Kurt

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Re: [Utah-astronomy] Steve Dodds & "1 Meter Mike" on channe 2
by Canopus56 07 Jun '08

07 Jun '08

Thanks, Patrick. That was an amazing major astro event for Utah as a whole and Steve and 1.75 meter Mike personally. >From the story, it sounded like it might be a left over mirror from the Manned Orbital Laboratory military space flight - the precursor manned spy satellite to Keyholes? If so, that in itself would be a major piece of space history. MOL was featured in a recent Nova broadcast. Perhaps Steve or Mike could take some photos of the new mirror and make a short presentation on one of the summer SLAS monthly meetings. To throw in my usual 2-cents, Mike is probably thinking in terms of building a private scope. Considering the size of such a project, as a contigency plan if his building program does not pan out, he might want to consider joining forces with the UofU's roboscope initiative. That would create the world's largest publically accessible roboscope and put the State on one leading edge of public astronomy. - Kurt (To the Trib's Shelia, if it is the MOL mirror, that's a 1/4 - 1/2 page article right there.) http://www.pbs.org/wgbh/nova/astrospies/ Nova Astrospies program 2-2008 MOL on Wiki http://en.wikipedia.org/wiki/Manned_Orbiting_Laboratory

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Steve Dodds & "1 Meter Mike" on channe 2
by Patrick Wiggins 06 Jun '08

06 Jun '08

http://www.kutv.com/mediacenter/local.aspx?videoid=43809@kutv.dayport.com&a… patrick

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