20 April 2007

Observing Location	VP
Observational Period	1045-1100 EDT
Atmospheric Conditions	Cloud Cover Scattered Clouds Temperature 72°F Wind Light Breeze Humidity Low Feels Like Very comfortable There are still some lingering wisps of cloud around but it has cleared out nicely and there is mostly light blue sky visible. Transparency Good Seeing I
Instruments	Brunton 8x21 compact binocular w/Welco gold shade 14 welder's filter - Charlie
Observing Party	Charlie Ridgway

Target Sunspots Constellation Ari Category Solar Time yyyymmdd.hhmm 20070420.1045 EDT Comments Distance Light Time 1.004633 AU 8ms Angular Size 31'53.4" Altitude 49.6° Heliographic Latitude (B0) -5.18° Heliographic Longitude (L0) 94.27° Position Angle (P) -25.62° Carrington rotation number (CR) 2055 I am not seeing anything. Space Weather is not showing anything either, but Active Region Explorer shows group 951 about half way from the meridian to the western limb.   Groups Spots R North 0 0 0 South 0 0 0 Total 0 0 0 R = (Groups * 10) + Spots)

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It doesn’t look like it could get much better for tonight, and tonight will be the best night of the weekend. I am a little sorry that tonight is the Columbia University public observing session for the month. I would get more time, and more observing, done at TotL (if I didn’t spend most of my time just talking to Peter and Kin), but I am going to go to Columbia since we only get to do that once a month during the school year and only when the weather is good, which is less than half the time.

Clear Sky Clock graphic

This hasn't been a particularly good month for observing so far. In fact it has been notably poor. I have gotten less observing done this month than I did in the dead of winter. Hopefully this weekend will correct that somewhat.

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Silently one by one, in the infinite meadows of heaven, Blossomed the lovely stars, the forget-me-nots of the angels. Henry Wadsworth Longfellow

Observing Location	Rutherford Observatory, Columbia University, New York, NY
Observational Period	1930-2230 EDT
Atmospheric Conditions	Cloud Cover Clear Temperature low 50s F falling quickly through high 40s F Wind Light Breeze Humidity Low Feels Like Cool I didn’t get a lot of eyepiece time so can’t comment too much on the conditions. Transparency Good Seeing II
Instruments
Observing Party	Charlie Ridgway Neil – Columbia University grad student Cameron – Columbia University grad student the public

I started out the night out on the roof top with my binocular and then moving onto the Dob to assist Cameron keeping things in the eyepiece while he was interpreting for people. I didn’t get much observing done as the number of people built quickly.

Target Moon Constellation Tau Category Lunar Time yyyymmdd.hhmm 20070420.1930 EDT Comments Lunation 1043 Phase Waxing Crescent Age 3.53d Distance Light Time (from earth) 365,947 km s Elongation ° % Illuminated 17.5% Magnitude -10.92 Angular Size 32.65’ Altitude 37.26° The Moon has moved up to the upper end of Taurus near the horns. It is a wide crescent but there is still earthshine visible. Langrenous is prominent on the edge of Mare Fecunditatis with its central peak visible. The other features I noted were dorsum on the mare floors. In Mare Crisium I could see Dorsa Oppel on the terminator side of the mare but I could not detect Dorsa Tetyaev on the limb side. Down in Mare Fecunditatis I was seeing Dorsa Geikie.

Target Venus Constellation Tau Category Planet Time yyyymmdd.hhmm 20070420.1930 EDT Comments Object Class Classical Planet Phase Waning Gibbous Elongation ° % Illuminated 72.12% Distance Light Time (from Earth) AU ms Distance (from Sun) Au Angular Size 15" Magnitude -4.07 Altitude 22°23’ Venus and the Moon were both easily visible when I arrived on the roof a half hour before the start of the session. I never looked at it in the scope feeling that the sky was already too dark by the time it was set up to be able to see anything but flare. Starry Night Starter graphic

Target 2P/Enke Constellation Ari Category Time yyyymmdd.hhmm 20070420.2000 EDT Comments Not Seen My object in arriving at the observatory before the start of the session was to try to observe the periodic comet Enke which is supposed to be a Mag 4 green fuzz ball on the western horizon right after sunset. I had checked online and knew that the comet was directly below the Pleiades but very close to the horizon. CalSky said the best time to see it was between 20.1 and 20.9 hours. I had difficulty finding the Pleiades with my binocular and never saw anything low on the horizon but planes. By the time we were into the recommended observing window that part of the sky had rotated behind a building as seen from the Dob which was the only instrument that can see that low on the western horizon. Starry Night Starter graphic

Target Saturn Constellation Leo Category Planet Time yyyymmdd.hhmm 20070420.2030 EDT Comments Object Class Classical Planet Elongation ° Distance Light Time (from Earth) AU hm Distance (from Sun) Au Angular Size "x" Ring Angular Size "x" Ring Inclination ° Magnitude +0.33 Altitude 66°36’ We looked at Saturn several times during the night as different people arrived and wanted to see it. I saw the moons Titan, Rhea and Dione, the band on the planet south of the rings and the shadow of the planet on the rings. Starry Night Starter graphic

Around 2100-2130 EDT The crowd started to thin out a bit and I moved into the small dome where Neil was running the 11” Cat and finished out the night there.

Target M81, NGC 3031 Constellation UMa Category DSO: SpGal Time yyyymmdd.hhmm 20070420.21## EDT Comments The fuzz ball was faint and small but easily seen. I asked about M82 but Neil said the FoV was too small for it to be there also.

Target M51, Whirlpool Galaxy, NGC5194 Constellation CVn Category DSO: SpGal Time yyyymmdd.hhmm 20070420.21## EDT Comments Not Seen There was a guy there who wanted to see M51 but Neil explained that its surface brightness was less than that of M81 and since M81 was faint we would not see M51 but he wanted to try anyway so the scope was spun and the dome after it.

Target M44, Praseape, The Beehive Cluster, NGC2632 Constellation Can Category DSO: OCl Time yyyymmdd.hhmm 20070420.21## EDT Comments Neil told the guy that the object was too big to fit into the FoV but he wanted to see it anyway so the scope was spun and the dome was spun and we saw a few bright stars that didn’t look like anything. I wasn’t able to find in with my binocular.

Target M35, NGC2168 Constellation Gem Category DSO: OCl Time yyyymmdd.hhmm 20070420.21## EDT Comments This one was a bit richer than M44 but again didn’t look like much in the time I had in the eyepiece.

Target Castor Constellation Gem Category Double Star Time yyyymmdd.hhmm 20070420.2200 EDT Comments This is a six star system. Castor A, Castor B and Castor C are optical doubles while each of them itself is a spectroscopic double. I could see an obvious close double without a clean split, the lower of the stars appeared brighter.

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Observing Location	TotL The closest street light to TotL to the west was out the last time we were here. It has been replaced with a lamp that is super bright and very bothersome. The closest light to the east is now burned out. If they replace it with a lamp of the same intensity as the one that has already been replaced we may not be able to observe from TotL until they burn down. We may have to move back to TPO>
Observational Period	2300-0100 EDT
Atmospheric Conditions	Cloud Cover Clear Temperature mid 40s F Wind Light Breeze Humidity Low Feels Like very cool The temperature dropped noticeably while I was there but according to the thermometer on the MONY building the temperature change was only 2°F. Peter reported that seeing had gone downhill while he had been there. Transparency Good Seeing II
Instruments	Teleport 10" Donsonisn reflector - Peter
Observing Party	Charlie Ridgway

As I expected would be the case I got more real observing in in my two hours with Peter and my similar amount of time at Columbia with the public.

Target M81, NGC3031 & M82, Cigar Galaxy, NGC3034 Constellation UMa Category DSO: Gal Time yyyymmdd.hhmm 20070420.23## EDT Comments We were able to see both galaxies in Peter’s scope. M81 is a spiral galaxy that we see more or less from the top down (or bottom up) and it is fairly large with and bright. It lies at the end of a right triangle formed with two stars. M82 is an irregular galaxy that is elongated like a cigar. I have more trouble making out M82 but I could see its elongation and orientation with respect to M81. It appears to the 10:30 of M81.

Target M94, NGC4736 Constellation CVn Category DSO: SpGal Time yyyymmdd.hhmm 20070420.23## EDT Comments The galaxy appears to be about five times as wide as it’s core. Its brightness falls off very quickly and at its is mostly a faint haze around an almost stellar core.

Target Saturn Constellation Leo Category Planet Time yyyymmdd.hhmm 20070420.23## EDT Comments We looked at Saturn several times here as well as different passers-by passed by. To my list of observed moons I added Tethys faint and below and near the south pole of the planet. I was able to clearly see the C ring but the Cassini division was much less distinct than usual although it was visible over a greater portion of the rings than I normally see it.

Target M106, Constellation CVn Category DSO: SpGAL Time yyyymmdd.hhmm 20070421.0011 EDT Comments We saw it but I didn’t make notes and don’t remember anything now so will have to edit this space after Peter refreshes my memory.

Target M51, Whirlpool Galazy, NGC5194 Constellation CVn Category DSO: SpGal Time yyyymmdd.hhmm 20070421.0019 EDT Comments We did see it from TotL and with less aperture than we had earlier at Columbia.

Target NGC5195 (M51A) Constellation CVn Category Time yyyymmdd.hhmm 2007 EDT Comments This is an irregular galaxy right next to and under the end of one of the arms of M51. It was discovered by Pierre Mechain at the time he discovered M51. It has previously had an interaction with M51 which has changed it from a spiral to an irregular shape. Photos of M51 and NGC5195: NASA/ESA SEDS

Target M63, NGC 5055 Constellation CVn Category DSO: SpGal Time yyyymmdd.hhmm 20070421.0050 EDT Comments Detected When I first got to the eyepiece I correctly identified its location but then changed my mind and placed it lower and much larger than its true position and size.