Astronomical Observations: 23 April 2010

Observing Location

Observational Period

2100-2200 EDT

Atmospheric Conditions

Cloud Cover	Clear
Temperature	62° F
Wind	Gentle Breeze gusting to Moderate Breeze
Wind Chill Effect Heat Index	° F
Humidity	Low
Barometric Pressure	29.94" Hg Rising (2)
KNYC METAR	240051Z AUTO 30009G15KT 260V350 10SM CLR 17/M04 A2997 RMK AO2 SLP138 T01671039
Feels Like	Chilly

Transparency	Fair
Seeing	II-III

Instruments

West Marine Raiatea 7x50 binocular - Charlie
6” Dobsonian – Columbia
~8” Cassiagrain – Columbia

I didn’t check to see which type of Cassiagrain telescope this was

14” Cassiagrain – Columbia

I asked the post-doc who was taking questions while people waited to get to the scope what kind of Cassiagrain telescope it was and he said he was a radio astronomer and didn’t know scopes. When I got to the scope I asked the doctoral candidate who was running it what it was and she didn’t know either.

Observing Party

Charlie Ridgway
Tom Clabough
Columbia astronomy students
public

I attended an astronomy lecture entitled The Physics of History at Columbia tonight. The talk was about how we can use subatomic particles as datestamps for historic events that are captured in geology (KT extinction), biology (dendrochronology) and astronomy (Big Bang). After the event there was public observing on the roof.

Target

Moon

Constellation

Leo

Category

Lunar

Time
yyyymmdd.hhmm

20100423.2100 EDT

Lunation	1089
Phase	Waxing Gibbous
Age	9d12^h30^m
Distance Light Time (from earth)	362,983 km ^1.21s
Elongation	120.10° E
% Illuminated	75.1%
Morning Terminator Colongitude (λ E)	30.94°
Evening Terminator Colongitude (λ W)	210.94°
Libration in Latitude	5° 37’
Libration in Longitude	-00° 39’
Magnitude	-11.2
Angular Size	33' 03"
Altitude	55.13°
Virtual Moon Atlas graphic

Comments

I first observed the Moon in the 6” Dobsonian out on the roof and was able to walk it up and down the terminator but since there was a line of people waiting to get to the scope I couldn’t spend a lot of time looking at anything. I did notice some apparent rinkle ridges in the floor of Mare Imbrium just south of Promontorium

Lunar Astronautical Chart

Toward the end of the night I got a chance to see Mare Imbrium filling the field of view of the 14” Cassiagrain scope. I was not permitted to focus the scope so my view wasn’t good even with my new glasses. I could not find the ridges I saw in the smaller scope but did see two faint young craters (Helicon and Le Verrier)out in the middle of the Imbrium plain.

USGS Geologic Lunar Atlas

Helcion

Statistics

Quadrant	NW
Area	NW part of Mare Imbrium
Long.	231.1° W
Lat.	40.4° N
Diameter/Length	26 km
Depth	1,910 m
Age (Baldwin)	(Imbrian period - from 3.2 Bya to present)
Best Observed	2 days after First Quarter, 1 day after Last Quarter
Description	Circular Formation. Forms a remarkable couple with Le Verrier. Few steep slopes supporting the craterlet Helcion E to the West. Few high walls supporting a craterlet to the SW. Flat floor filled with lava. Small central relief

References

Lunar Aeronautical Chart (LAC): LAC-24
USGS Geologic Lunar Atlas: I-602
Lunar Topographic Orthophotomap (LTO)
Atlas of the Moon (Rukl): 10
Amateur Astronomer’s Photographic Lunar Atlas (Hartfield): 6 e4
Exploring the Moon Tryough Binoculars and Small Telescopes (Cherrington): 177, 197 III

USGS Geologic Moon Atlas graphic

Le Verrier

Statistics

Quadrant	NW
Area	Central part of Mare Imbrium
Long.	20.6° W
Lat.	40.3° N;
Diameter/Length	20 km
Depth	2,100 m
Age (Baldwin)	Erastosthenian period (3.2 Bya to1.1 Bya)
Best Observed	2 days after First Quarter or 1 day after Last Quarter
Description	Circular formation. Forms a remarkable couple with Helcion. Pretty steep slopes supporting Le Verrier T to the S. Pretty high walls damaged to the N. Flat floor. Line or crest. Small mountain.

References

Lunar Aeronautical Chart (LAC): LAC-24
USGS Geologic Lunar Atlas
Lunar Topographic Orthophotomap (LTO)
Atlas of the Moon (Rukl): 11
Amateur Astronomer’s Photographic Lunar Atlas (Hartfield): 6 d4
Exploring the Moon Tryough Binoculars and Small Telescopes (Cherrington): 177, 199
Moon Observer’s Guide (Grego): 106, 132

Target	Engagement Ring
Constellation	CMi
Category	Asterism
Time yyyymmdd.hhmm	20100423.2110 EDT
Location	Catres du Ciel graphic
References	Binocular Highlights: 34
Comments	I looked with the hand-held binocular but didn’t see anything. Binocular Highlights says “Depending on your sky conditions, just about any size binoculars should show this grouping.” My sky looked murky.

Target

Saturn

Constellation

Leo

Category

Planet

Time
yyyymmdd.hhmm

20100424.2125 EDT

Object Class	Classical Planet
Elongation	145.05° E
Distance Light Time (from Earth)	8.67 AU 1^h 12^m
Distance (from Sun)	9.51 AU
Angular Size	19.1"x17"
Ring Angular Size	43.3"x1.58"
Ring Inclination	-2.10°
Magnitude	0.8
Altitude	47.62°
Stellarium graphic

Comments

I observed the planet in the small Cassiagrain telescope in the small dome. I was able to focus the scope so got a good view and saw Titan off to the right and a very faint moon to the left probably about 5 ring diameters away.

Target

Mars

Constellation

Cnc

Category

Planet

Time
yyyymmdd.hhmm

20100423.2150 EDT

Object Class	Classical Planet
Elongation	96.02° E
Distance Light Time (from Earth)	1.22 AU 10^m 10^s
Distance (from Sun)	1.66 AU
Angular Size	7.65"
Magnitude	0.6
Central Meridian	13°
Altitude	59.36°
Meridian graphic

Comments

We observed Mars in the 6” Dobsonian and it just looked like an orangs circle. I was not able to see any surface markings on it. In the binocular it looked very nice sitting in a squashed square with δ Cnc, γ Cnc and M44. They probably filled 2/3 of my 6.5° FoV.

Catres du Ciel graphic

Target

M44, Beehive Cluster, Praesape, NGC 2632

Constellation

Cnc

Category

DSO: OCl

Time
yyyymmdd.hhmm

20100423.2155 EDT

Magnitude	3.5
Surface Brightness	13/sq’
Size	80’
Shape	nearly circular
Difficulty	(6)
Distance	580 ly
Location	Where is M13 graphic
References	Deep Sky Observer’s Guide: 111, 113, 117-118, 140, 175 Stars and Planets: 190, 192, 252, 284 Binocular Highlights: 45 The Observer’s Sky Atlas: E8

Comments

The rest of the public had gone and the woman driving the 6” Dob was looking for targets so I suggested M44 since we were in the neighborhood anyway. The cluster didn’t look anything like what I am used to seeing and we had to find it twice to be sure of it. All of the stars are a uniform blue-white color and of fairly equal brightness. There might have been an underlying ground glass impression behind the bright stars but if there was it was just below my limits of vision.

Target

M81

Constellation

CMa

Category

DSO: Gal

Time
yyyymmdd.hhmm

20100423.2200 EDT

Magnitude	7
Surface Brightness	12/sq’
Size	18’
Shape	elongated
Difficulty	4
Distance	12 M ly
Location	Where is M13 graphic Stellarium graphic
References	Deep Sky Observer’s Guide: 22, 56-57, 71, 171, 178 Stars and Planets: 175, 190, 193, 234 Binocular Highlights: 35 The Observer’s Sky Atlas: N8

Comments

This was the last object for the night in the 6” Dob. We were in the general area of it with a low power eyepiece but I don’t know the star field so couldn’t pick anything out.

Observing Location

TotL

Tonight is the first night we have had to contend with the sprinklers this year. The ones along the fence inside the oval don’t look like they will be as much problem this year as in the past as they don’t hit the fence when aimed at TotL. They came on at 2340 EDT,which is 20 minutes earlier than last year, and shut down at 0005 EDT. There is one sprinkler in the North Fields that could be problematic with a stiff north wind and the closest Oval heads could pose problems on any south wind.

Observational Period

2230-2430 EDT

Atmospheric Conditions

Cloud Cover	Isolated Clouds
Temperature	58° F
Wind	Calm
Wind Chill Effect Heat Index	° F
Humidity	Low
Barometric Pressure	29.98" Hg Rising (2)
KNYC METAR	240251Z AUTO VRB04KT 10SM CLR 14/M05 A3000 RMK AO2 SLP150 T01441050 51023
Feels Like	Cool

Transparency	Fair
Seeing	II

Instruments

West Marine Raiatea 7x50 binocular - 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
Tom Clabough

Target

Saturn

Constellation

Leo

Category

Planet

Time
yyyymmdd.hhmm

20100423.2240 EDT

Object Class	Classical Planet
Elongation	144.97° E
Distance Light Time (from Earth)	8.67 AU 1^h 12^m
Distance (from Sun)	9.51 AU
Angular Size	19.1"x17"
Ring Angular Size	43.3"x1.58"
Ring Inclination	-2.09°
Magnitude	0.8
Altitude	50.19°
Stellarium graphic

Comments

The view in the TelePort was much better than that through the ~8” Cassiagrain scope in the small dome at Columbia. I could see four moons around the planet. There was a thin stripe of shadow separating the rings from the planet.

Target

Moon

Constellation

Category

Lunar

Time
yyyymmdd.hhmm

20100423.2345 EDT

Lunation	1090
Phase	Waxing Gibbous
Age	9^d 15^h 15^m
Distance Light Time (from earth)	364,499 km ^s
Elongation	121.63° E
% Illuminated	76.2%
Morning Terminator Colongitude (λ E)	32.33°
Evening Terminator Colongitude (λ W)	212.33°
Libration in Latitude	5° 56’
Libration in Longitude	-00° 54’
Magnitude	-11.3
Angular Size	32' 57"
Altitude	40.28°
Virtual Moon Atlas graphic

Comments

I stole a quick look and got an eyeful of Clavius. The overall brightness in the FoV was very comfortable. There is a string of craters arcing across the floor of the plain, each one a bit smaller than its predecessor.

Virtual Moon Atlas graphic

Digital Lunar Orbiter Photographic Atlas of the Moon

Lunar Astronautical Atlas graphic

USGS Geologic Moon Atlas graphic

Crater	Diameter
Rutherfurd	56 km
Clavius D	26 lm
Clavius C	21 km
Clavius N	13 km
Clavius J	12 km

Just beneath Clavius N is a Catina composed of three overlapping craters which I did not see.

Statistics

Quadrant	SW
Area	South limb
Long.	12.4° W
Lat.	58.8° S
Diameter/Length	28 km
Depth
Age (Baldwin)	2
Best Observed	1 day after First Quarter or Last Quarter

References

Lunar Aeronautical Chart (LAC): LAC-125, LAC-125
USGS Geologic Lunar Atlas: I-706, I691
Lunar Topographic Orthophotomap (LTO)
Atlas of the Moon (Rukl): 72
Amateur Astronomer’s Photographic Lunar Atlas (Hartfield): 10 d3, 12 a2, 14 g3, 14 h3
Exploring the Moon Through Binoculars and Small Telescopes (Cherrington): 6, 20, 40, 41, 108, 112, 173, 175, 177. 195, III

Target

M81, Bodes Galazy (Nebula), NGC 3031 & M82, Cigar Galaxy, NGC 3034

Constellation

UMa

Category

DSO: Gal

Time
yyyymmdd.hhmm

20100423. EDT

	M81	M82
Magnitude	37	8.5
Surface Brightness	12/sq’	12/sq’
Size	18’	10’
Shape	elongated	ellipse
Difficulty	4	3
Distance	13 Mly	13 Mly
Location	Where is M13 graphicWhere is M13 graphic Stellarium graphic
References	Deep Sky Observer’s Guide: 22, 56-57, 71, 171, 178 Stars and Planets: 175, 190, 193, 234 Binocular Highlights: 35 The Observer’s Sky Atlas: N8

Comments

M81 was easier tonight than it was the last time we looked at it in Peters 6” refractor but still not an easy object. I don’t hold out much hope of seeing it in my binocular despite what Binocular Highlights says about it (M81 seen in 10x50 binocular easily while M82 only seen intermittently). Karkoschka says M81 id doable in a finder scope (6x30) and M82 needs binoculars (12x50). I don’t think I even detected M82 in the 10” TelePort.

First Hop