February 2006 - Utah-Astronomy - mailman.xmission.com

Re: Comet Pojmanski
by Chuck Hards 25 Feb '06

25 Feb '06

And WHAT a comet it was, eh, Patrick? People who didn't see it never really believe my description- truly a Great Comet. Coming as it did so close on the heels of Kohoutek, the press ignored it, to the loss of many millions of people, sadly. I didn't make it up this morning due to illness (fatigue from a killer work schedule, really), but Kurt made it and we are going to try and rendezvous up there Sunday morning around 4:30-5:00 am, weather permitting. > From: Patrick Wiggins <paw(a)trilobyte.net> > Comet watching from Little Mountain. Memories of > Comet West... __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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145 CMa - the Winter Albireo - a colorful after-work double winter double Feb-Mar
by Canopus56 25 Feb '06

25 Feb '06

145 CMa (HD056577) - the Winter Albireo - is at it's most favorable low declination position (J071636.00-231912.0) for 41N op's. 145 CMa is visible in small refractors after sunset from urban light polluted skies. The Belmont Society Colorful Double Star List describes pi Gem as "orange/blue-green" while Mullaney's _Celestial Harvest_ gives this double an effusive recommendaton. The primary of this colorful multiple is a v4.8 K4III star at an estimated distance of 536 parsecs. The discover designation - HJ 3945 - attributes first recorded sighting to William Herschel. At 536 parsecs and G236.50-05.22, this double sits west of Canis Major "down-wind" in the Orion Arm from Sol, in a area rich in small open clusters. Current (Epoch 2000) CCDM data on 145 CMa (CCDM 07166-2319) is: C PA sep mag A 4.8 B 055 26.6 6.8 145 CMa is about 3 degs east of omi2 CMa. A courtesy star hopping finder chart is provided at: http://members.csolutions.net/fisherka/astronote/finder/CMa_145StarHops.jpg 145 CMa current is low on the horizon from 41N ops - at about only 20 degrees in altitude at sunset. 145 CMa can be star-hopped or right-angle swept by starting at omi2 CMa. From my light polluted v3.0 urban skies, I began at del CMa and swept north about 3 degs to omi2 CMa. omi2 CMa was just barely naked-eye visible in the light pollution. Due to light pollution, there were really not any good landmarks to star hop to 145 CMa. Finding this double is a bit challenging in light polluted skies. Since 145 CMa is a direct east declination sweep from omi2 CMa, I simply used the lowest feasible magnification, with the largest TFOV, about 1 deg in this case - and then counted about 3 1/2 ep views east of omi2 CMa until I saw a small double that looked like 145's namesake - Albireo. In a small alt-az 60mm refractor under urban Bortle class 8 mag 3.0 light-polluted urban skies at 22x, 145 CMa lives up to its namesake as the Winter Albireo. It is a nice, distinct, intense blue-gold pair about 22" apart. But unlike it's summer namesake, the Winter Albireo is over 500 parsecs distant, while the "real" Albireo is about 125 parsecs away. On increasing magnification to about 78x, the Winter Albireo the colors fade and somewhat dim in a small refractor. In contrast, the bet Cyg double retains is golden-jewel crispness under higher magnification. All-in-all, this was a nice 15-20 minutes of easy after-work beer-in-hand viewing at 41N. The Belmont Society Colorful Double Star list can be found at: http://www.belmontnc.4dw.net/dblstrs.htm - Canopus56 __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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Planetary mini-marathon possible for the next few nights
by Canopus56 25 Feb '06

25 Feb '06

It's been some time - I think May 2000 or 2001 - when we had most of the major planets aligned on the same side of the sky for easy viewing. By spinning my plastic planetica, it doesn't look like they will realign until 2011. So for, now getting a good overview of all the major planets on one night means picking a good night where half are visible at sunset and the other half at sunrise. Now is such a time. Kinda of a planetary version of the upcoming Messier Marathon. Last night, I started at nautical twilight at an Avenues park with Mercury in the west - which currently is at its most brillant. At astronomical twilight, Saturn's in Cancer and Mars is near Taurus. Uranus is another 10 degs in altitude above Mars on the west horizon, but it sets too early to be seen through thick atmosphere. At 5:45am this morning, I pulled into the Little Mtn parking lot based on Chuck's tip on Comet C/2006 A1. Venus was a brillant mag -4.8. Jupiter and its satellites are also especially brillant. Neptune and Pluto are in Capricorn, which just rises above the east-southeast horizon. Both are too low to be seen. At 5:00 to 6:00 am, the skies from Little Mtn were very clear. The Cygnus portion of the galactic arms runs east west about 30 degrees above the eastern horizon, ending at the galactic core in Sgr near the southern horizon. The Cygnus and Aquila Rifts were easily seen with the naked-eype and with binos, details in the Sgr cloud structures between us and the galactic core. Sco is high and transiting on the south horizon in its summer orientation. It was nice seeing both the antigalactic center M42 in Orion and its galactic center counterpart - M8 the Lagoon Neb on the same night. I didn't have a thermometer, but the temperature seemed to be around 30-35 degrees and did not feel oppressively cold at all. As I was unpacking the car at home at about a quarter to 7:00, The thin crescent of the 27 day-old Moon rose in the morning over Wasatch. I've seen the 2 day old crescent at sunset many times. The morning 27 day crescent is more spectacular. It has a more 3-D feel to it. Of this shallow sky group, Mercury will set over the next couple of weeks. The thin crescent of the new Moon will not return until around March 4. For a couple of hours of viewing and not much driving, currently you can get a good major planet tour all within 12 hours. - Canopus56 (Kurt) __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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London Planetarium to Close
by Patrick Wiggins 25 Feb '06

25 Feb '06

The stars at one of central London's well-known tourist attractions will go dark for good this July. Madame Tussauds waxworks, the owner of the London Planetarium, has decided to close the facility as the company shifts its focus from science education to entertainment. Score: Entertainment 1 Education 0

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Comet Pojmanski
by Chuck Hards 24 Feb '06

24 Feb '06

I'm considering a pre-dawn sojourn up to Little Mountain early Saturday, to see comet Pojmanski, weather permitting. Anybody else interested? I plan on it being a bino trip, no telescope this time. If I like the views in the binos I'll take a bigger scope next weekend. It also might make an interesting composition for a photo, being so close to Venus. I'm on the digest, please send a copy to my address directly if replying, thanks. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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Mercury up and bright
by Canopus56 24 Feb '06

24 Feb '06

For those you with a couple of seconds to stick some binos or a scope out the door now, Mercury should be up and bright - through 6:45pm. Here's an ephermis: ******************************************************* Date__(UT)__HR:MN Azi_(a-appr)_Elev APmag Illu% **************************************************** 2006-Feb-25 00:00 * 239.5606 29.3497 -0.23 45.108 2006-Feb-25 00:15 * 242.7484 26.8641 -0.23 45.060 2006-Feb-25 00:30 * 245.7945 24.3076 -0.23 45.011 2006-Feb-25 00:45 * 248.7162 21.6903 -0.22 44.963 2006-Feb-25 01:00 * 251.5300 19.0212 -0.22 44.915 2006-Feb-25 01:15 C 254.2516 16.3084 -0.22 44.866 2006-Feb-25 01:30 C 256.8957 13.5595 -0.22 44.818 2006-Feb-25 01:45 N 259.4763 10.7811 -0.22 44.770 2006-Feb-25 02:00 N 262.0070 7.9795 -0.22 44.721 2006-Feb-25 02:15 A 264.5007 5.1605 -0.21 44.673 2006-Feb-25 02:30 A 266.9696 2.3297 -0.21 44.625 2006-Feb-25 02:45 269.4262 -0.5077 -0.21 44.576 2006-Feb-25 03:00 s 271.8824 -3.3462 -0.21 44.528 - Canopus56 (Kurt) __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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Smorgasbord of potential pleasure targets for Brandt 3/4/06 training session
by Canopus56 24 Feb '06

24 Feb '06

Observing session time frame: 3/04/2006 7:00PM LT to 03/04/2006 9:00PM Local time - same as - 03/05/2006 2:00UTC to 03/05/2006 4:00UTC - subject as always to cloudy weather in March: Total Days 31 Mean Clear Days 7 Mean Partly Cldy Days 8 Mean Cldy Days 16 This will be a Moon and bright star night because the Moon is up; it will not be a DSO night. Although the focus of the session is training on physical use of the dome and scope during cold weather, a smorgasbord list of potential pleasure targets, from which a couple can be selected for the March 4 Brandt session include the following. Az and Altitude coordinates for stellar objects listed below are for 3/04/2006 7:00PM. Lunar targets are for the terminator position at 40.3 East longitude at 8:00pm local time. Calculated characteristics for the Brandt scope are listed in Part II. - Enjoy Canopus56(Kurt) I. Smorgasboard of targets I(A). Lunar At 3:00 UTC (8:00pm local time), Rukl's lunar terminator estimator tables (p.218-219 Rukl's Atlas of the Moon) puts the lunar terminator at 40.3 East lunar longitude. The favorable libration on March 4 per the RASC Handbook is at the equator on the east limb. Potential showcase objects for the evening are: Crater Hercules Crater Gutenberg Montes Pyrenaues Crater Janessen - and possibly - Rupes Cauchy North to South, some interesting features at 8:00pm might be: 1) 80 N region - Crater deSitter (65km) 80.1 N, 39.6 E, Rukl Map 5 2) 80 N region - Crater Billard (90km flooded creater) 74.6 N, 37.5 E, Rukl Map 5 3) 50 N region - Mare Firgoris 52 N, 40 E (surface albedio effects), Rukl Map 6 4) 50 N region - Crater Hercules (69 km dark material on floor) 46.7 N, 39.6 E, Rukl Map 14 5) 40 N region - Crater Maury (17.6 km) 37.1 N, 39.6 E, Rukl Map 15 6) 20 N region - Crater Fray (20 km, corroded, flooded crater) 16.6 N, 40.2 E, Rukl Map 25 7) 10 N region - Rima Cauchy (240 km - east 20km only visible) 9 N, 37 E, Rukl Map 36-37 8) 10 N region - Rupes Cauchy (120km fault similar to the Rupes Recta - the Straight Wall - east 20km only visible), Rukl Map 36-37 9) 10 S region - Crater Gutenberg (74km - complex crater floor) 8.6 S, 41.2 E, Rukl Map 48-47 10) 20 S region - Crater Bohnengerger (33km) 16.2 S, 40 E, Rukl Map 58-59 11) 20 S region - Montes Pyrenaues (250km mountain range) 14 S 41 E, Rukl Map 58-59 12) 40 S region - Craters Matius (88km), Fabricus (78km) and Janessen (190km - old degraded crater with wide rilles and ridges), approx. 42.9 S, 42 E, Rukl Map 68 13) 60 S region - Crater Vlacq (89km), Rukl Map 75 14) 60 S region - Crater Nearoh (76km) 58.5 S, 39.1 E, Rukl Map 75 15) 80 S region - Crater Boaguslausky (97 km) 72.9 S, 43.2 E, Rukl Map 74 16) 80 S region - Crater Scott (108km) 81.9 S, 45.3 E, Rukl Map 74 (P.S. Some of the crater names may be misspelled. I typed them up quickly and from handwritten notes.) I(C). Bright, Colorful Multiple Stars in the zenith hole from the Belmont Colorful Double List, by Azimuth Id Con J2000 AzAlt SpecPri V V2 Sep Notes 1) psi05 Aur Aur J064643.20+433448.0 Az072.75 Alt+74.32 G0V 5.4 8.4 36.2 Belmont note: yellow/blue; CCDM06467+4335, R Aur 2) pi. Gem Gem J074731.20+332512.0 Az092.73 Alt+60.53 M0III 5.15 5.3 11.4 Belmont note: orange/bluish triple with 3rd at 92"; CCDM07475+3325 3) HD046296 Aur J063419.20+380448.0 Az095.32 Alt+76.04 K0 6.6 10 43.2 Belmont note: yellow/blue/blue quad; CCDM06343+3805, STF 1103 4) HD035295 Aur J052512.00+345136.0 Az176.15 Alt+84.08 K1pvar+ 6.5 8.6 31.2 Belmont note: yellowish/orange; CCDM05252+3451, HJ 2268 5) HD033203 Aur J051019.20+371800.0 Az216.98 Alt+85.71 B2II 6.8 7.1 1.6 Mullaney: gold & bluish-red; CCDM05103+3719, STF0644 6) 56 Per Per J042438.40+335736.0 Az244.32 Alt+76.53 F4V 5.9 8.7 4.5 Belmont note: gold/yellow; CCDM04246+3358 I(C) Position of Planets above horizon at 2:00 UTC, 7:00pm (from Your Sky) by Azimuth Body RA_Dec Az_Alt Saturn 8h 31m 11s +19Â° 39.7' / 103.734 44.930 Mars 4h 22m 40s +23Â° 21.9' / 220.527 68.236 Moon 3h 17m 50s +22Â° 19.1' / 244.382 57.662 Mercury 23h 42m 2s +1Â° 39.6' / 268.217 4.580 Setting I(D). Separation resolution testing stars by Azimuth Argyle has published a set of matched resolution test stars. Here are some stars spread across the scope's Dawes and Rayleigh limits. None are well-placed near the zenith hole: Id Con J2000 AzAlt SpecPri V V2 Sep PA PA Epoch Other names 1) HD050700 Mon J065408.52-055108.6 Az150.40 Alt+38.93 A6Vn 6.39 6.6 1.3 170 2002 CCDM06541-0551, WDS06541-0551, STF 987, HIP033154 2) HD015328 Cet J022759.88+015739.2 Az237.25 Alt+34.64 K0III 6.45 6.7 0.52 29 2002 CCDM02280+0158, WDS02280+0158, KUI 8, HIP011474 3) HD006886 Psc J010939.12+234739.8 Az272.66 Alt+35.00 F0 6.65 6.8 0.62 290 2002 CCDM01097+2348, WDS01096+2348, BU 303, HIP005444 4) HD208132J Cep J215137.32+654510.1 Az334.55 Alt+28.31 A1m 6.37 6.7 1.4 145 2002 CCDM21516+6545, WDS21516+6545, STF2843, HIP107893 Argyle, R. (ed). 2004. Tables 2.1-2.7, Test Stars for Binocular through 600mm Telescopes. In Observing and Measuring Visual Double Stars. Springer. ISBN 1-85233-558-0 http://www.springer.com/ II. Some Brandt telescope characteristics: II(A). Resolution criteria: Airy disk radius 0.692 arcsecs Dawes limit 0.579 arcsecs Rayleigh limit 0.692 arcsecs Airy disk diameter 1.384 arcsecs Airy disk diameter linear size 22.546 microns Linear resolving power - theoretical 108 line pairs/mm Linear resolving power - practical film 60 line pairs/mm FWHM angular size 0.579 arcsecs FWHM linear size 9.425 microns II(B). Eyepiece fl/TFOV data at sky brightness ZLM 5.5 mags, 20.0 MPSAS: Note: These limiting magnitudes will not apply to near quarter-phase Moonlight sky on March 4. The telescopic limiting magnitude may be substantially lower due to Moon light. TFOV estimates and useful magnifications apply. Eyepiece focal length 9 mm Eyepiece AFOV 52 degrees Telescopic magnification 373.3 power Magnification per inch: 46.7 useful for: Double stars Telescope TFOV 0.1 degrees Telescope TFOV 8 arcmins Telescope TFOV 501 arcsecs Limiting telescopic magnitude - stellar, color index 0: 14.4 mags Eyepiece focal length 15 mm Eyepiece AFOV 52 degrees Telescopic magnification 224.0 power Magnification per inch: 28 useful for: Specific planetary lunar detail Telescope TFOV 0.2 degrees Telescope TFOV 14 arcmins Telescope TFOV 836 arcsecs Limiting telescopic magnitude - stellar, color index 0: 14.4 mags Eyepiece focal length 20 mm Eyepiece AFOV 52 degrees Magnification per inch: 20.6 useful for: Planetary and lunar details Telescopic magnification 168.0 power Telescope TFOV 0.3 degrees Telescope TFOV 19 arcmins Telescope TFOV 1114 arcsecs Limiting telescopic magnitude - stellar, color index 0: 14.2 mags Eyepiece focal length 52 mm Eyepiece AFOV 48 degrees Telescopic magnification 64.6 power Magnification per inch: 8 useful for: Small clusters and galaxies Telescope TFOV 0.7 degrees Telescope TFOV 45 arcmins Telescope TFOV 2675 arcsecs Limiting telescopic magnitude - stellar, color index 0: 13.3 mags III. Telescopic limiting magnitude test areas There are no good pre-mapped Clark TLM fields in bright open clusters near the zenith on March 4. Possible bright but lower altitude TLM fields pre-mapped by Clark and in the RASC 2006 Handbook are: Id Con J2000 Alt-Az coord Notes M67 Cnc J085006.00-115300.0 Az107.35Alt+36.42 Northwest quadrant of M67; mag range: 10.6-21.3; In the RASC 2006 Handbook NGC225 Cas J004342.00+614648.0 Az321.64Alt+44.30 Clark note: 20 stars mag 9+ Transiting off-zenith Landolt standard star fields are: Area Con J2000 Alt-Az coord Notes SA97 Ori J055725.92+000140.8 Az167.04Alt+48.52 Centered on 60 Ori, HD040210, mag range 7-14, N=37 stars SA98 Mon J065209.60-001742.0 Az148.13Alt+44.24 Centered on HD050209, mag range 8-13, N=30 with 46 supps to mag 18 Clark, R.N., 1990. Star Clusters for Finding Your Limiting Magnitude. Appendix C in Visual Astronomy of the Deep Sky, Cambridge University Press and Sky Publishing http://www.clarkvision.com/visastro/ RASC. 2006. RASC Observer's Handbook. Annual. http://www.rasc.ca/publications.htm Landolt1973: Landolt, A. 1973. UBV photoelectric sequences in the celestial equator selected areas 92-115. 1973AJ.....78..959L; CDS Cat. VI/19 1996yCat.6019....0L http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?1973AJ.....78..959L Landolt1992: Landolt, A. Jul. 1992. UBVRI photometric standard stars in the magnitude range 11.5-16.0 around the celestial equator. 1992AJ....104..340L ; CDS Cat. II/183A/ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1992AJ....104..340L __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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pi Gem - an colorful after-work double winter double
by Canopus56 24 Feb '06

24 Feb '06

pi Gem, currently favorably positioned (J074731.20+332512.0) for 41N op's, is visible in small refractors after sunset from urban light polluted skies. The Belmont Society Colorful Double Star List describes pi Gem as "orange/bluish triple" with an AB separation at 21" and the third at 92." The primary of this colorful multiple is a v5.3 M0III star approximately 172 parsecs distant. The pi Gem multiple at ~ 172 parsecs at G186.76+25.54 lies about 25 parsecs beyond the anti-galactic center end of our Local Bubble. Current CCDM data on pi Gem (CCDM 07475+3325, STF1135) are: C Pa Sep mag A 5.3 B 214 21.0 11.4 C 341 91.9 10.4 There does not appear to be a Sixth Orbit Catalogue plot for this multiple system. pi Gem is about 3 degs north east alf Gem. A courtesy star hopping finder chart is provided at: http://members.csolutions.net/fisherka/astronote/finder/Gem_piStarHops.jpg pi Gem can be star-hopped or right-angle swept by starting at alf Gem. Using an eyepiece that approximates a 1 deg TFOV, find HR2936 (HD 61295), a v6.2 F6II, star about 1 deg north east of alf Gem. >From HR2936, there are two right angle sweeps to pi Gem. The first right angle sweep involves going 2 eyepiece FOVs east of HR2936, then north in declination 1 1/2 eyepiece FOVs. The second right angle sweep route involves sweeping in north declination about 4 eyepiece FOVs to omi Gem - the first unmistakeable bright v4.9 F3III star on a north dec sweep from alf Gem. Then sweep east two 1 deg eyepiece FOVs, and then south one eyepiece FOV until an apparent, but unmistakeable, two color double is seen. For some reason, I found the longer route through omi Gem easy to execute with an alt-az mount. Once the position is mentally fixed, pi Gem can be direct swept to using a 3 deg 1x dot finder. Center the scope alf Gem and use bet Gem as a intermediary reference line. Estimate where the edge of the 3 deg finder intersects alf-Gem-bet-Gem reference line at about a 60 degree angle. Direct sweep to that location. Odds are pi Gem will be somewhere in a 1 deg TFOV eyepiece view. In a small alt-az 60mm refractor under urban Bortle class 8 mag 3.0 light-polluted urban skies at 22x, pi Gem retains its nice orange/blue color, albeit washed out. At 47x and 78x, the increased size of diffraction disk of the M0III primary brought out more of its redish color. I did not detect the v11.4 C component under these light-polluted conditions. I did not have the position angle (PA) reference for the third C component at the time of viewing and could not definitely confirm its location among the options within the star field. A Schaefer limiting magnitude computation for these light pollution conditions indicates the TLM for this small refractor is at or near the v11.4 of the C component, so it may have not been visible under those light-pollution conditions seen and small aperature used. All-in-all, this was a nice 15-20 minutes of easy after-work beer-in-hand viewing. The temperatures last night were not so oppressively low as in prior winter nights at 41N. - Canopus56 (Kurt) __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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Clark refractor ap and fl?
by Canopus56 23 Feb '06

23 Feb '06

What are the aperature and focal length of the Clark Refractor? Do we have setting circles installed on it? - Canopus56 (Kurt) __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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ISS crosses the Moon
by Patrick Wiggins 23 Feb '06

23 Feb '06

Excellent movie of ISS crossing in front of the Moon: http://science.nasa.gov/spaceweather/swpod2006/22feb06/ISSLunarTransit06021… Patrick p.s. Don't blink.

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