9 January 2010

Observing Location	TotL
Observational Period	1730-2200 EST
Atmospheric Conditions	Cloud Cover Clear Temperature 27° F falling to 20° F Wind Moderate Breeze Wind Chill Effect 17° G falling to 11° F Humidity Moderate Barometric Pressure 30.15" Hg Rising Feels Like Frigid Transparency Excellent Seeing
Instruments	Naked-eye - Charlie Teleport 10" Donsonisn reflector – Peter 2" Pentax 40mm, 70° FoV, 31.8x 2" TeleVue Nagler 17mm, 82° FoV, 74.7x 1.25" TeleVue Nagler 13mm, 82° FoV, 97.7x 1.25" TeleVue Plossl 7mm, 82° FoV, 181.4x
Observing Party	Charlie Ridgway Peter Tagatac

On the way up to TotL I stopped at Bethesda Fountain to see if there was anything visible in early twilight. I saw Jupiter (but assumed Jupiter had already set so figured it must be Mars), and α and Β Aur.

On arriving at TotL I could see Antares and six of the Pleiades.

Target ε Aur Constellation Aur Category Eclipsing Binary Star Time yyyymmdd.hhmm 20100109.1730 EST References The Observer's Sky Atlas: N6 Comments Stellarium graphic Tonight I judged ε Aur to be close in brightness but slightly dimmer than ζ Aur (Mag. ). Later when Peter arrived I repeated the assessment with him and I still felt ε was the dimmest of the kids while Peter felt that it was slightly brighter than ζ but dimmer than η Aur (Mag. ). [Karkoschka lists ζ Aut as a variable irself with a range of Mag. 3.7 to Mag. 4.0. If that is the case we are comparing the grightness of one variable star to that of another and it would be impossible to get a valid brightness estimate by comparing ε to ζ. 13Jan10]

Target Satellite Constellation Aur, Tau Category Satellite Time yyyymmdd.hhmm 20100109.1746 EST Comments While observing ε Aur an unknown, faint satellite passed through the center of Auriga and on below Antares. It looks like it was the Cosmos 1025 Rocket which passed from N through E and faded in the SE about that time. At maximum altitude it was Mag. 4.9.

Target Jupiter Constellation Aqr Category Planet Time yyyymmdd.hhmm 20100109.1830 EST Comments Object Class Classical Planet Elongation 38.38° E Distance Light Time (from Earth) 5.73 AU 17m 40s Distance (from Sun) 5.00 AU Angular Size 34.3" x 32.1" Magnitude -1.6 Central Meridian I/II/III 39.8 °/160.7°/296.3° Altitude 15° 6' Stellarium graphic Planetary and Lunar Visiblility graphic Jupiter was very low and as a consequence of Earth’s atmosphere it appeared a uniform salmon color with no evidence of banding or polar hoods. Two moons were observed in Peter’s hand held 10x binocular and all of the moons were visible in the telescope at low power.

We discussed what the bright evening star we were seeing in the SW might be. I thought Jupiter would have already set remembering how high it was the last time I had seen it and adding in the passage of time since I had made that last observation. What I did not factor into that calculation was that we were out much earlier than usual. Peter didn’t think it was Mars as he felt that would rise much later. Mercury and Venus are setting before the Sun so there wasn’t much left and no matter where Saturn was that looked too bright to me to have been Saturn. Eventually we got out Peter’s Palm and I checked in Planetarium to see what was bright in the SW. Sure enough it was Jupiter. The information page said Jupiter was at a little better than 21° altitude. But both Peter and I estimated Jupiter’s actual altitude to be higher than that. I estimated a bit more than 23° and I always seem to estimate low. So that begs the question:

?

How does the height of the observer affect the altitude at which an object is perceived? It seems to me that there should be an effect there. If two people, one 4’ and the other 5’ tall both look at the horizon the shorter person will perceive the horizon to be nearer than the taller person. Height of Eye Distance to Horizon 4 feet 2.228 nautical miles 4.330 kilometers 6 feet 2.863 nautical miles 5.302 kilometers horizon distance (nautical miles)=1.17 x sqrt(eye height) (feet) Each person would be looking down to see his horizon, the taller person looking down farther. If they each measure up 20° from their horizon it seems that the point in the sky that the shorter person is looking at would be higher in the sky than the point the taller person is looking at. Now we are in an area of mathematics that is beyond my ability to remember what happened all those eons ago when I straggled through Mr Rifkin’s geometry lessons, or was he trig. Looking in Wikipedia for some help I find that there are three types of horizons true horizon; visible horizon; and astronomical horizon Wikipedia graphic I have always used the true horizon when making altitude estimations. This may be why I am always looking low for satellites. But even of two people of two different heights looked at the same angle above the astronomical horizon they should still be looking at different places in the sky since in the example above the astronomical horizon would be 2’ lower for the shorter person.

Target M38, NGC 1912, Cr 67 Constellation Aur Category OCL Time yyyymmdd.hhmm 20100109.1850 EST Size 25 x 25 ly Distance 5,700 ly Age 278.6 My Location Where is M13 graphics Cartes du Ciel graphic References Deep Sky Observers Guide: 120-122 The Observer's Sky Atlas: N6 Comments Faint; “A” shaped 3 levels of brightness 19 stars easily counted

Target M36, NGC 1960, Cr 71 Constellation Aur Category OCl Time yyyymmdd.hhmm 20100109.1900 EST Size 12 x 12 ly Distance 4,100 ly Location Where is M13 graphics References Deep Sky Observers Guide: 120-122 The Observer's Sky Atlas: N6 Comments delta-shape several levels of brightness 12 stars counted in brightest levels

Target M31, Andromeda Galazy, NGS224 & M32, NGC 221 Constellation And Category Gal Time yyyymmdd.hhmm 20100109.1905 EST Size 5,585 x 4,189 ly Distance 2,400,000 ly/2,400,000 Location Where is M13 graphics M31 & M32 appear in the same location Cartes du Ciel graphic References Deep Sky Observer's Guide: 11, 16, 18, 42, 47, 49, 50, 53-55, 74, 75, 77, 146 The Observer's Sky Atlas: N0 Comments I actually saw M32, the companion galaxy, before the Andromeda Galaxy. The Andromeda Galaxy had an obvious brightening at the center.

Target M37, NGC 2099, Cr 75 Constellation Aur Category OCl Time yyyymmdd.hhmm 20100109.1913 EST Size 18 x 18 ly Distance 4,100 ly Age 346.7 My Location Where is M13 graphics References Deep Sky Observers Guide: 120-122 The Observer's Sky Atlas: N6 Comments 3 levels of brightness 13 stars counted

Target M45, the Pleiades, CR 42 Constellation Tau Category OCl Time yyyymmdd.hhmm 20100109.1915 EST Size 13 x 13 ly Disance 410 ly Age 135.2 My Location Where is M13 graphics Cartes du Ciel graphic References Deep Sky Observer's Guide: 10, 16, 17, 95, 98, 107, 112, 113, 114-115, 116, 119, 132, 175 The Observer's Sky Atlas: E3 Comments We counted the stars naked-eye and this time I came up with eight.

Target M1, Crab Nebula, NGC 1952 Constellation Tau Category DifNeb, SNR Time yyyymmdd.hhmm 20100109 EST Size 11 x 7 ly Distance 6,300 My Location Where is M13 graphics Cartes du Ciel graphic References Deep Sky Observer's Guide: 8, 20, 26, 162, 163-164, 177, 181 The Observer's Sky Atlas: E3 Comments Not Seen This was Peter’s main quarry for the night and although considerable time was spent looking for it he could not find it. He thinks we have seen it from TotL before but, like most other objects, I have no memory of it.

Target M42, Orion Nebula, NGC 1976,/M43, NGC 1982 Constellation Ori Category DifNeb Time yyyymmdd.hhmm 20100109.2015 EST Size 40 x 28 ly/9 x 7 ly Distance 1,600 ly/1,600 ly Location Where is M13 graphics M42 & M43 appear in the same location Cartes du Ciel graphic References Deep Sky Observer's Guide: 8, 10, 13, 27, 50, 93, 96, 97, 99-100, 101, 102, 103, 105, 111, 141, 142, 175, 176 The Observer's Sky Atlas: E4 Comments Stellarium graphic We observed the Orion Nebula first with a nebula filter and it was very impressive. There was a stripe of nebulosity that was just above three bright stars below the trapezium. As the stripe passed the last of the three stars it made a right turn and continued down at least as far as it had gone horizontally. Messier's drawing of M42 shows this well. Wikipedia graphic Above the trapezium there was another horizontal band of nebulosity also going out to the west. There was nondescript nebulosity at M43. The faintest of the trapezium stars was difficult to see. Without the nebula filter there was still a lot of nebulosity in M42 but the extensions to the west and south were gone. M43 was detectable but that is about all. Down at Iota there appeared to be some nebulosity but we felt that it might also have just been that we were looking at a bright star.

Target M79, NGC 1904 Constellation Lep Category GCl Time yyyymmdd.hhmm 20100109.2100 EST Size 118 x 118 ly Distance 42,100 ly Location Where is M13 graphic Cartes du Ciel graphic References Deep Sky Observer's Guide: 75, 87-88 The Observer's Sky Atlas: E4 Comments Therre was a brightnening at the center of the cluster. The gradient in brightness from the edge to the center was very smooth.

Target M41, NGC 2287, Cr 118 Constellation CMa Category OCl Time yyyymmdd.hhmm 20100109.2120 EST Size 26 x 26 ly Distance 2,300 ly Age 242.7 My Location Where is M13 graphics Cartes du Ciel graphic References Deep Sky Observer's Guide: 112, 123-124 The Observer's Sky Atlas: E6 Comments little b____ lots of stars, three levels of brightness stars were primarily red and blue

Target M35, NGC 2168, Cr 82 Constellation Gem Category OCl Time yyyymmdd.hhmm 20100109.2130 EST Size 16 x 16 ly Distance 2,200 ly Age 96.3 My Location Where is M13 graphics Cartes du Ciel graphic References Deep Sky Observer's Guide: 122, 177 The Observer's Sky Atlas: E7 Comments Some color (red and light blue) is showing but not as pronounced as that in M41.

Target M50, NGC 2323, Cr 124 Constellation Mon Category OCl Time yyyymmdd.hhmm 20100109.2150 EST Size 13 x 13 Distance 2,900 ly Age 124.7 My Location Where is M13 graphics Cartes du Ciel graphic References Deep Sky Observer's Guide: 122-123 The Observer's Sky Atlas: E8 Comments three levels of brightness bright stars are mainly red

Target Mars Constellation Leo Category Planet Time yyyymmdd.hhmm 20100109 EST Comments Object Class Classical Planet Elongation 152° 42' W Distance Light Time (from Earth) 0.698 AU 5m 48s Distance (from Sun) 1.64 AU Angular Size 13.4" Magnitude -1.0 Central Meridian 243° Altitude 23° 49' Planetary and Lunar Visibility Meridian graphic graphic We noted Mars rising above the trees but didn’t point the scope at it.