Tuesday, February 26, 2008

M81 & M82 in binoculars from Central Park

Session name: 20080225.2000

I completed this short session observing the sky to the south. My light observing kit was packed up and the tripod collapsed. A turn towards the north revealed the Great Bear climbing vertically up a darker sky. I thought it novel when I glanced at the middle star of the bear's tail (the handle of the Big Dipper). Mizar and Alcor was an easy split.

How sly. Teasing. I'm going now.
Ahhh......why not? It'll only take a second.

All of Ursa Major - from nose out to the Three Leaps of the Gazelle - was seen naked eye. I looked north of 29- & 23 UMa to see sigma UMa and 24 UMa.

Uh oh!

The Takahashi 22x60 bins were unpacked and mounted on the tripod in less than a minute. Sighting on 24 UMa, in the bins, I found my orientation on the right triangle shown in the picture on the left. From there I looked in the direction of M81.

Initially, it took some effort to see M81, but after keeping my eyes to the eye cups and scanning the field M81 stood up to direct vision as a football-shaped fuzzy blob next to two other stars. M82 was much more trickier and required averted vision the whole time. That was at the very edge of my visual confidence that I noted in my log book its location relative to the nearby field stars with a question mark as a dim strand of extended light, distinct from a faint star.

Not a spectacular sight where the galaxy shows volume and detail, only the ~10 ~20 arc seconds brightest part of its nucleus was observed. I think that's quite an achievement for 22x60 binoculars from Central Park.

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Monday, February 25, 2008

Planets offer pleasing views

Session name: 20080224.1900

A cold session with a light breeze chilled exposed cheeks and shook the scope. Early in the session clear skies yielded slowly to accumulating clouds entering from the west. Thin, semi-transparent sheets gathered beneath Orion and ultimately coated a large part of the sky by 10PM EST. Over the course of the observing session a half dozen passersby and dog walkers stopped for breathtaking views of Saturn. Charlie and Kin were absent as well as familiar dog owners.

Mars still reveals some features in the eyepiece despite its size at 9.4", much smaller than the 15.6" of 08 DEC '07. First, it is obviously a pinkish-red disk compared with the nearby stellar pinpricks. It has area and with a sprinkle of imagination one can sense volume. Secondly, surface features of different albedo and tone were apparent. A light breeze caused the disk to dance in the field of view, but with firm scope and steady seeing I could see clearly Chryse Planitia, a martian basin with a high albedo. This circular white area contrasted with darker marial regions to the north and south. The southern marial region was larger and broader across the disk than the northern one which appeared more localized above Chryse. I was unable to detect the northern polar cap which I had seen in previous sessions. Magnifications used 90x, 120X and 240x, finally settling on the 7mm's 120x magnification for a bright, crisp view of the diminutive red disk.

Saturn was splendid this session. Passersby remarked the same. If you plan to consider sidewalk astronomy, this is an ideal season because Saturn is sure to delight all that see him. I can't think of any other object in the night sky that thrills the pedestrian observer with disbelief and astonishment.

When the air calmed, the scope would settle long enough to drink in long views of the ringed planet and its satellites. I heard gasps from those who took a look in the eyepiece. At 120x magnification, one could easily appreciate Saturn's characteristic parts and shape. With more scrutiny during the calm moments, many features were observed.

On the disk of the planet, a salmon-pinkish toned belt ran parallel across the disk beneath (south) the ring. Of the ring system, Cassini Division on each side was a challenge but discernible. The A-ring offered a translucent glow which contrasted with the Division and whiter, opaque B-ring. Perhaps a shadow provides the darker lineal feature on the south side of the ring that crosses the planet. I am confused because tonight Saturn is at opposition and no shadows should be displayed. Like a full Moon, the Sun is shining directly on the planet from our point of view on Earth offering no shades of relie

Saturnian moons Titan, Rhea
, Tethys were clearly visible, pinpoints of light created by sunlight reflected off their surface. I suspected a prick of light inside Rhea's orbit but had wavering confidence. Checking planetarium software StarryNight at home, those pings of photons turned out to be Dione.
Lastly, I suspected a point of faint light about 5 Titan-Saturn-separations distant on the same side as Titan. Field notes agreed with the planetarium program indicating this unusal moon at magnitude 10.92. There is not much room for the limiting magnitude in this scope under these skies. (Magnitude 11.6 with previous measurements using NGC225 and NGC1647.)

I finished of this session with a practice run for GAN'08. I was able to detect stars as faint as 4.7 above Times Square. I don't propose that NYC has dark skies but that my observation skills, visual acuity, and confidence allow me to see pinpoints of light, even if more contrats is desired.

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Globe At Night - 2008

Globe At Night - 2008
(magnitude charts )
Naked eye observations to assess sky brightness around the globe is underway today.

Globe at Night is the organization that coordinates the event, prepares instructions, provides training, magnitude charts, and circulars announcing the event. The comparative star charts enable you to assess easily your sky's transparency by comparing your observation of Orion with that of the charts.

In 2007, GAN had collected 8,491 observations. Support the 2008 effort by participating from NYC, one of the brighter places on the globe. Download & print the magnitude charts and look up and choose the star map that resembles your view and then submit a report to GAN. It's that easy.

Since I was out last night (Session 20080224.1900), I turned my attention to Orion. He stood a little west of manhattan-south - about 280* azimuth - which placed him roughly above Times Square from point of view. Thin stratus clouds advanced from the west and gathered beneath him. Given the conditions I was able to see all the stars that are shown on the Magnitude 4 chart and even more. My sky was not as rich as the one depicted in a Magnitude 5 chart . My guess is magnitude 4.6 ~ 4.8, considering my visual acuity.

If it is a clear weekend night stop by the top of the Great Lawn for naked eye and telescope viewing of the Heavens. In addition to Orion, observe some of the celestial treats in other easily constellations like Mars in Taurus, galactic clusters in Canis Major, beautiful and colorful multiple star Monoceros, among many, many more visible from the heart of New York City.

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Sunday, February 24, 2008

2nd Annual ISAN & Yuri's Night

ISAN logo

12 April 2008 is the 2nd Annual International Sidewalk Astronomy Night (ISAN), same day as Yuri's Night. Two celebrations, one for astronomy, another for manned space program.

19 May 2007 was last year's date but we were rained out here. The following day it cleared enough where a few groups set up around the city to hold the first annual International Sidewalk Astronomy Night from Central Park.

I haven't decided where I'll be this year. I'll coordinate with others,especially folks from AAA of NYC I may return to the south side of the Great Lawn but am considering a higher traffic area with good exposure from south to west. Moon, Mars, and Saturn will no doubt be the highlights. I'll post updates in the future.

Snipped from Yuri's Night '08
12 April 1961 marks mankind's first flight into space with Soviet cosmonaut, Yuri Gagarin. 20 years later to the date the Space Shuttle was launched on her maiden flight, STS-1.

I attended the party at CUNY Graduate Center where Greg Olsen shared his experience with training and flight with the Russians to the ISS. I really enjoyed his presentation. Other speakers included astronaut Tom Henricks and mathematician Dr. Edward Belbruno. After the event, I picked up an autographed book from Ed Belbruno, Fly Me to the Moon.

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Eclipse handout

Click and then print larger image. Folding instructions below or at PocketMod.

For the recent total lunar eclipse, I prepared a handout for the pedestrians. The objective was to provide information listed below, space availability was the governing factor. Not everything made it or was to be trimmed down to fit space.

The handout consisted of:
- brief description & time table of the event
- Danjon Brightness Scale to describe color and brightness vaules
- basic moon map (using NASA Lunar Landing Map)
- illustration of moon's passage through shadows (Espenak's)
- list of NYC astronomy groups
- a list of astronomy resources in NYC

I relied on freely available material, particularly Fred Espenak's work available on the NASA web site. I did model my black and white version based Fred Espenak's illustration for easier reading in dimmer lighting. In fact, I made few a drawings, one which showed the geometry of an eclipse and the "phases" (shape) of the moon as the event unfolded. Those images are forever stuck in a corrupted file on a USB stick :{ a lesson learned the hard way } and I had no time to make them up. Instead I whipped up a version similar to this one.

I realize there is much room for improvement but I like the start and like its utility. Better planning and considering both sides of the paper will improve the design and effectiveness of future handouts. I find it too easy to provide too much detail and just as hard to distill to the essential elements while keeping it engaging. Also, copy should not really be dense, pictures being a thousand words augment what I might be explaining.

I am working on a boilerplate to adapt to regular sidewalk sessions. I am even looking to standardize on a form that can be used by sidewalk astronomers for 2nd Annual International Sidewalk Astronomy Night (ISAN).

(Will follow up with my own illustrated directions.)
On a recent trip, my daughter returned with an origami book and folding paper for omiage (gift giving/souvenier). I have been hooked on paper folding since and thought of applying it to the handout. Via my Moleskine interest and paper pdas, PocketMod came to mind. I chose this attractive and convenient paper book format for 8 usable pages per side of a folded sheet. When you get the knack, this fold can be done in seconds. In the simplest of descriptions a piece of paper is:
- folded in half along each axis: length and width
- unfolded and then re-folded the length of the paper
- fold each half, making quarters across the length of the page
- with printed side up, sharpen the fold across the width
- tear the lengthwise fold, center of the sharpened width
- lay the torns sides flat
- fold the paper along the length
- flatten and square up booklet

Comes with two accessible pockets to tuck other notes away.

Lunar Landing Map

21 February 2008 Eclipse Predictions by Fred Espenak, NASA's GSFC

A pop-up window with paper folding instructions from this page. Beneath Step #2 and to the right of Step#4, click the "Folding Guide" button.

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Thursday, February 21, 2008

Set up for the eclipse

Clouds did not diminish our ambition to watch and share. Bruce sets up the Scope that had a huge line all night long. The Tak refractor and bins cooling down. When the skies cleared we'd be busy all night long. Along the promenade wall there were more people sharing their optics. for the pedestrians to get a closer look. So much that once again I didn't take any photos of the eclipse or the crowds.

Fantastic Lunar Eclipse Event in NYC

Session name: 20080220.2010

This special session away from the lawn at Carl Schurz Park event was a terrific success. Overcast skies allowed the Moon too punch through thinning clouds during the beginning of the event. Over the duration of the eclipse somewhere between 150 ~ 200 people would come by - the skies cleared & cold temps - and share the experience of the full moon transform before our eyes. The moon took on pearly red color, most people exclaimed the same when they noticed it. Bruce Kamiat, Rick Davis and myself manned three large scopes with half a dozen more tripod-mounted binoculars. Team TotL'er Kin, Rich Rosenberg and other AAA'ers provided commentary to many of the questions being asked by the people. Many walked around with bins hanging from their necks. For the lunar ecclipse event, optics are not as important for the type of casual observation were did throughout the night.

My setup consisted of 22x magnification Takahashi bins and the 4" Takahashi refractor. The bins were aimed at the Moon all night, raised and lowered to accommodate all heights and ages. The telescope had Saturn in a field that was magnified at first 90x but conditions improved that a magnification of 120x was steady and clear.

John Pazmino and I prepared different handouts with info on the eclipse and other NYC astronomy resources. John and others responded to the needs of many persons while waiting their turn to look in the eyepiece.

(Lesson learned about preparing material for the public. More about that later)

I must say - probably parroting every other amateur astronomer - that these public outreach events are exciting. People thank us for sharing but they provide the Joy for me: their reception, their expression, their reaction, their agreement. Nature is fascinating and the public is open, receptive, to wonder and awe. While 20 million (?) people sat and watched stars of American Idol, I wonder how many of us looked to the real stars for an exquisite show.

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Thursday, February 07, 2008

Crescent moon alert

Moon Watch at sunset tonight.

Tonight at sunset 5:20PM EST, look for the new crescent moon a little greater than the width of fist off the southwestern horizon. A very young moon, the 18h35m moon rides atop a steep ecliptic which provides a greater elongation from the Sun than an inclined ecliptic, dramatically increasing chances of success. As the Sun sets below the horizon, the moon is setting also but remains above the horizon longer. The moon is just shy of 7 degrees above the horizon at sunset. Further, the sky darkens and contrast increases to help sight the slender, wispy lunar limb. With its angle of attack the limb will appear like a smile, perhaps with some lumpiness. Locally, the moon sets at 6:06PM EST.

Here in NYC, I recommend a pair of binoculars at the least to spot it and then try naked eye after it is located. Forecast calls for clouds at 5:20PM EST but they've been wrong before. Go ahead and try.

The Sun sets at azimuth 250┬░at 5:20PM EST. The crescent moon hangs above that point in an "11:30" position, as noted in the illustration above. If sky conditions are agreeable, I anticipate a sighting about 14 ~ 18 minutes after sunset.

Regardless, try for the crescent tonight and then submit your report to the organization linked above.

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