Binocular astronomy session from Central Park

Session name: 20090109.2123

Location: Top of the Lawn, Central Park
Site Classification: Urban
Dark Sky Scale, Bortle: Class 8, City Sky
Seeing Scale, Antoniadi: --
Transparency: --
NELM: ~mag 4.7
Weather: Clear sky, cold evening, light pollution beams from specific sources along the southern skyline radiated sharply up into the sky. Mostly calm air with some light breezes (Beaufort 2)
Moon: 14d10h waxing gibbous, near Full.
Equipment: Tak Pack, 22x60 Binoculars
Observing Party: Peter
Passersby: 14
Objects observed: M41, NGC1981, M42 & Trapezium, Mel25/Hyades, M45/Pleiades, epsilon CMa*, NGC2362/tau CMa Cluster, H3945/ADS5951 (same fov as 2362), NGC2354*, M93, M47, Sigma1171 in M47, M46*, Saturn & Titan, Moon.
* attempted but not seen.

Clear sky and a waxing, gibbous Moon seen on my way home from work, enticed a quick session beneath the stars. Later in the the evening, I looked out the window to see the Winter Hexagon and the brighter stars of Canis Major and most of Orion.

Arrived later than usual at TotL with the Tak Pack and laid out the optics beneath the tripod to acclimate to the cold air. While waiting snapped some photos of the southern skyline and constellations with a Canon G10. About an hour after arriving, I began an observing session with binoculars.

Canis Major (CMa) rose above the treeline to my east, sitting like an obedient dog looking up to Orion (Ori). I count 10 stars of the not-so-bright constellation excluding the head,nu^2 appearing faintest. Within the Sword of the bright constellation Orion, I can see the fuzzy patch of theta and two stars of iota. A glance to bright Taurus in the west, high in the sky, clearly reveals Hyades (Melotte25) and Pleiades (M45).

Back in CMa, M41 in the Tak bins is faint for an otherwise bright open cluster because it suffers from being low in the NYC sky. I count 24+ stars in an estimated area of 30', uneven distribution with a denser concentration to ESE.

A few different groups of passersby visited at this time, including the police. Each was able to observe M41, with relative ease. I described how an open cluster signifies a group of stars that are "born"from the same gas and dust cloud, sharing the same proper motion in space. Over time - a very long time - the stars under the influence of the Milky Way's gravity will be pulled like taffy and the cluster extends across greater distances. I point to Pleiades, Hyades and the Big Dipper as specimens of the same ilk. I often describe open clusters like leaves that fall from a tree into a river. At first they all move down stream together but over time they separate and go their own way.

M47 is a more impressive open cluster to show to the public since its brightness, size, shape are easily discerned and the additional feature of a double Sigma 1171 is a bonus. In the binoculars, I can easily count 15 for the first level of bright stars and the double star. (I see a schnauzer shape in these stars. I may have said terrier in the past but it is a mustached dog.) There are more that are fainter that probably increases that number. Nearby open cluster M46 is not seen because its surface brightness is too low to be observed through the bins or even the 4" Tak refractor. My best view of M46 has been with the 10" to see the cluster and planetary NGC2438.

Afterward the Tak bins were turned to one of my favorite fields of view through the Tak bins: Orion's Sword. This 2° span frames the bright nebula M42 and the Trapezium between NGC1981 and iota Ori very beautifully. With steady air and mount, the Tak bins resolve the Trapezium, theta^1 Ori, where the western star of the "Mickey Mouse triple" resolves to two stars bringing the count to four. A nearby trail of three stars in an E-W direction constitute theta^2 Ori.

The Mexican Jumping Star, a.k.a. tau CMa Cluster, NGC2362, is an open cluster that surrounds magnitude 4.4 tau CMa. 4 stars persist in a clockwise arc from 4 to 11 o'clock. Dark adapting in the eyepiece yields many more stars that flicker at the edge of resolution. This cluster seems to be star rich, its treasures slightly beyond the reach of these bins in the city sky.

Debbie, Ben, and Pooch stopped by. We turned the bins on to Saturn, situated above the trees and south of the Leo's rear end. I was able to see Saturn with flat, stubby wings extended and Titan to its west. Debbie and Ben had a difficult time seeing more than the disk of Saturn, but Ben clearly spotted Titan. Despite not being the ideal instrument to observe Saturn,the view improves as Saturn climbs higher in the sky.

Last object observed was the Moon, high in the sky in Gemini - a neck breaker for tripod mounted bins. Before packing up for the session and looked on the bright orb if only for a moment. I was flabbergasted by the site and couldn't constrain myself form uttering how spectacular she looked. The terminator produced a rugged and attractive western lunar limb. My attention was drawn to craters Pythagoras and Carpenter to the north, then looked south along the limb to a dark patch of Oceanus Procellarum where it mixes with Sinus Roris. I wonder if libration is favoring this region.

15 minutes prior to curfew a pair of midnight shift police stop by. They ask about the skies and what's of interest. One asks whether I've see the northern lights followed by a story of her friend's reaction to observing them: it was a religious experience.

Oh! I can appreciate that because that's how I describe every night in Central Park beneath stars and mingling with the constellations and regular passersby.

20070204 - Risings and settings through the window

Here are some shots of objects seen setting and rising on Sunday evening. Displayed in shooting order.


Venus shines brilliantly above the rooftop while Mercury is observed setting between the valley of two buildings. This shot taken through the window.

Color shot taken after Mercury set behind the building. This shot taken through the window.

A shot of the moon through a window that faces manhattan-east with camera aimed to the northeast. Moon rises, occulted by church spire. The reflected image's brightness is attenuated beautifully to make out the mare and other lunar features.

Here is Orion rises, camera is looking out the same manhattan-east window, but now points to celestial south east.

20070203 - better skies for naked eye

Session name: 20060703.1920
Equipment: Teleport TP-10 & Fujinon 7 x 50 FMTR-SX


The cab transported the scope & I up to Mariner's Gate. This is the usual entrance for Top of the Lawn observing sessions and it has a small grade hill right at the start. In fact, to the south just on the other side of the playground is the highest point in Central Park, Summit Rock. The summit, at 141 ft./43.0m, is 1 ft/0.30m higher than Vista Rock which sits on the far side of Turtle Pond at the south end of the Great Lawn. (Climbing up Belvedere Castle, one reaches the highest point in the park.) Summit Rock's great elevation bleeds along this edge of the park, a small ascent I sort of dread.

Walking up the grade I look through the naked trees seeing the Winter Hexagon and Orion blatantly in the sky. It does look clear. Bundled in layers of clothing, my jacket is tucked in my backpack to avoid overheating. Catching my eye to the northeast is the rising Moon maybe 2½° ~ 3° in altitude. A striking buttery yellow, a honey moon hue - she is large! The branches and limbs can't conceal this girl -- she's much too large. I lost sight of her as the foreground buildings occult her view and I arrive at TotL.

I set up the scope and put the fan on to get it cooling off. I looked around feeling at home. Last month there weren't many nights I got out so I was looking forward to this one. While waiting for scope time, I spent time using a pair of my favorite instruments: mine eyes.

The February 2 essay of the book, 365 Starry Nights, Chet Raymo refers to a small illustration that shows a section of sky looking south. He asks, "Can you find Orion on the drawing above?" I think for most of us we'd find it with no problem. When one easily gets their bearings, not only is Orion apparent but one can see a trail of constellations: Lepus, Columba, Puppis, Canis Major, Monoceros, Canis Minor, and a dense river of dots showing the path of the Milky Way. Chet describes how both dogs have a pair of stars of unequal brightness and Canis Major's is more widely separated. The lines created by the pairs are almost perpendicular.

Canis Minor's pair are Procyon & Gomeisa. Canis Major has the brightest evening star Sirius coupled with Mirzam, Arabic for "announcer". Canis Major's stars are brighter than its counterpart in Canis Minor.

Look further south in Canis Major two stars that are part of the big dog's hind quarters, Wezen and Adhara. Adhara, the brighter one, is west of the fainter Wezen. Low in declination these stars don't rise that high in altitude. Jumping west, I look for Furud, zeta Canis Major, a magnitude 3 star. The low elevation and the approaching gegenschein radiating from the CitiGroup building both present challenges to Columba. It takes a clear, transparent sky to pick these stars up, ranging from magnitudes 2.65 to 4.37. Magnitude 4+ is difficult at low altitudes approaching and beyond celestial south. The gorgeous Manhattan skyline and a dark night sky collide.

The scope had cooled down and maybe a dozen people, a blend of friends and first timers, passed over the course of this session. Moon was shown only to a few as it was low, stressing the dobsonian to a seemingly horizontal recline. A survey of the different objects consisted of:

• Solar System: Saturn
• Open Cluster: M35
• Planetary Nebula: NGC2932, Eskimo Nebula
  
• Bright Nebula: M42 & M43
• Multiple Star: Trapezium

I didn't look so hard as the seeing was poor. Saturn was still soft at 100x but large enough for the people to recognize and admire. Personally, I preferred the naked eye skywatching. I recall looking to the west seeing Aries hanging perpendicular in the sky, dancing past the Pleiades & Hyades, into the sky describes above. Higher up approaching zenith, Gemini attracts attention. I'm waiting patiently for the clear, transparent night when M35 appears to glint for my naked eye.

And it was cold! The MONY clock flashed 24°/-5°C but it felt much, much colder than that when the wind gusted. Throughout the night, Charlie & I listened to the nearby tree crying of the cold: wheeee, wheee, wheee. It wasn't difficult to decide to pack the scope around 11~ish when the clouds came in.

20070117 - Rasky Tables

Session name: 20070117.2035

Since 2003 I purchase the Royal Astronomical Society of Canada Observer's Handbook from John Pazmino. I see it often referred in print as the "OH" and hear it called the "Observer's Handbook", but for reasons unknown or forgotten I call it "Rasky". The 2003 copy has a few notes scribbled in on the margins of some All-Sky maps. That copy timestamps the year when my earnest observing program began in the Fall.

2003. October 2003. (in the same vein as Bond.)

In the following years, checkmarks accompany notes in the margins of two sections in the Chapter NEBULAE AND GALAXIES, both written by Alan Dyer. The sections, The Messier Catalogue & The Finest NGC Objects, contain tables organized by season. I use them as convenient checklists for DSO objects observed. The intent is to check off objects observed only from TotL.

With this in mind, I planned to journey in the Winter Sky led by Rasky. The Messier objects in the table listed are, in order of right ascension reading columns across:

M1...............M45
M36............M37............M38
M42............M43............M78
M79............M35............M41
M50............M46............M47
M93............M48

Three objects in the list above are very challenging. I won't call them impossible because two of them just required larger optics to finally get captured. From the middle of Central Park I have seen all but M1, M46, and M78 with the Takahashi 4" refractor. It took the Teleport 10"reflector to add green ticks to M1 and M46. To date, I have not observed M78 from TotL or anywhere else. Most of the open clusters, except M46, have been observed in optics as small as 7x50 binoculars, even handheld.

My favorites on the list are M1, M42, and M37. Noteworthy is the background Milky Way sky around the Aurigae clusters. We can't see, at least haven't seen, the Milky Way from TotL but in the eyepiece I can see and feel the grainy, whitish, background. I don't know if I would use the word nebulousity but I wouldn't hesitate to call the sky crunchy.

This session I was surprised not to have resolved M1 confidently. Similar to a session in late December with Kin, I suspected a spot in the 1.1° field of view at 75x. Even though I sketched it where I thought it to lie relative to the field stars, I can't say I absolutely saw it. There have been only two TotL sessions that M1 was positively observed by myself and others, no filters in each case. M78 continues to remain quieter than contrast permits.

M46 strikes me as similar in character as M37 though fainter and slightly less dense. They are both pretty large and rich with faint stars. At 25' that is just smaller than the Full Moon. In all my TotL observations, the planetary nebula, NGC2438, in northern part of M46, escapes detection. I can recall sessions at the other end of the lawn, TPO, where Ben & I would scour the sky around M47 hunting for this cluster. There is a distinct obvious red star on the trail between the two but the other end was always empty, until TP10's glass turned on it. I have since returned with the 4" only to resolve the 2 or 3 brighter stars that lie in a NW-SE line on the SE edge of this cluster. Without having seen the cluster, the faint light of the hundreds or thousands of stars that expresses this type of nebula, resists discovery.

I bounced around the sky a lot. In spite of the absence of other TotL'ers, about a dozen and half people still passed by, stopping to have peeks through the scope. Early on M41 or M42 were the two objects I put most in the eyepiece and I provided the soundbite of "the leaves in the river" description for open clusters or the stellar nursery for the Great Orion Nebula. Later, others would be treated to a marvelous view of Saturn with 3 moons aligned to the west. In all 5 moons were observed including Enceladus hugging the inside track almost in line with Tethys, Dione,and Rhea. The disk's shadow becoming a black hairline but still greater than fine line of Cassini Division. (Is opposition close?) Since I was in Leo at one end of the Sickle, I pushed the scope up to the other end, checking on NGC2903. I took in the view of a very small, very dim, low contrast nucleus but didn't dare share this after showing Saturn.

Occasionally, I deviated from the Messier list observe other nearby NGCs. Leaving M35, a worthwhile open cluster in both bins and scope, I pulled the scope down and nudged it east to NGC2392, the Eskimo Nebula, treating my eye to color and the blinking effect. From M93, I pushed the Dob west into Canis Major to observe NGC2362, Tau Canis Majoris Cluster. This delightful little open cluster nestles the bright tau CMa in a arrowhead-shaped nest. Like most open clusters, I prefer to observe them in low power, wide field. Just my preference but I like the blushing, unresolved glow that they can display. Sometimes the scope just blows them apart where a different kind of study is performed.

I won't give up trying to check off M78 in the winter sky table, as I didn't with M1 and as I don't with M110. I'll try and try hoping that I happen to be looking at those two faint stars when all the factors are favorable and a faint nebulousity paints the sky. I don't expect the Wow! factor other than filling the red square with a green check mark.