Thursday, July 27, 2006

Observing locations in Central Park

Courtesy of Microsoft's Windows Live Local here is a map of some the observing locations in Central Park. Click on the photo to visit their Virtual Earth mapping app displaying my urban astronomy outposts.
7 pushpins mark the places and showing this blog's namesake at Pin #1.

Bracketing the New Moon

Panels left to right: young crescent(1d19h53m), new moon (0.0d), last crescent (28d17h28m)
red mark indicates libration
snippings from Virtual Moon Atlas


Session Name: 20060726.1900
--------------------------------------------------
Location: Top of the Lawn (TotL), Central Park, NYC (Google Map of
where I was)
Site Classification: Urban
Date/time: 26 July 2006, 7:00PM ~ 10:30PM
Sunset: 8:17PM
Moonset: 9:25PM
Handheld Binos: Fujinon 7x50, fov 7.5°
Tripod-mounted Binos: Takahashi 22x60, fov - 2.1°
====================================
Weather History
Transparency/Seeing (1 worst - 5 best): 2/2
NELM: --
Conditions: Low thick clouds floated above a very hazy sky along the horizon.
Observing party: Charlie and me
---------------------------------------------------


Mission accomplished: our first opposing crescents.

Mother Nature could not get the best of us. At 8:25PM from TotL, I spotted the setting young 1d19h53m waxing crescent Moon through seemingly heavy haze and some clouding above the tree line along the western horizon in handheld Fujinon 7x50 bins. I then put the crescent Moon in the tripod-mounted Tak 22x60 bins. Typically, a 3.2% illuminated disk does not present any difficulties. However, in spite of these challenges today, a 150° arc of crescent was teased from the white background sky.

The crescent shape appeared to extend the length for 2:00 ~ 7:00. The greatest width of the illuminated portion appeared around 5:00~ish. The contrast was low and the crescent was faint so I really didn't notice any kind of uneven illumination. I looked for any hint of Mare Australe but didn't get any. I was thinking that the bins were limiting because I couldn't increase the magnification. As the sky darkened and the Moon descended a small gain in brightness was realized. The gain was not substantially large but large enough that a naked eye sighting was possible. This was confirmed by a few other persons besides Charlie and myself.

Not what I had in mind but Charlie mentioned this was our first opposing crescent moons. I would have rather captured yesterday's crescent moon which would have resulted in a 39 hour interval. With today's observation this yields a 62h50m interval.

At 8:40pm the crescent was seen naked eye. I could only make out a quarter of the arc, like 90°. I had this same impression the entire time until it set behind the trees. The crescent Moon sank nicely into a small nook created by overlapping trees.

We shared the view with folks who stopped. Most memorable was the mom and 3 children. I invited them to have a look and offered to lower the tripod. Mom asked them twice but they said it was okay. I handed the mom my 7x50 bins suggesting that she relax her gaze and described where to look. She got the crescent pretty quickly. The kids said they wanted to look so down went the tripod for them. They all were able to see it saying how thin it was. While the bins were low another couple of ladies stooped down to give it a try. It was obvious when they got it as the ooohs and ahhhs were expresed with a lot of excitement.

Once again I got to demonstrate how Charlie and I bracketed the New Moon by observing the last and young crescents. This is more commonly referred to as "opposing crescents". The Tak bins were the Sun, one of the women was Earth, and my trusty mechanical pencil was the Moon. A small sweep of my arm past the bins with narration at three points explained it clearly to all that was willing to listen.

Can't keep what you have unless you give it away.

Wednesday, July 26, 2006

Young crescent moon attempt - a turkey

Walking into Battery Park there was a turkey in the lawn. A turkey!! (an omen)

Session Name: 20060725.1900
--------------------------------------------------
Location:
Battery Park, NYC (Google Map of where I was)
Site Classification: Urban
Date/time: 25 July 2006, 7:00PM ~ 9:30PM
Sunset: 8:18PM
Moonset: 9:00PM
Handheld Binos: Fujinon 7x50, fov 7.5°
Tripod-mounted Binos: Takahashi 22x60, fov - 2.1°
====================================
Weather History
Transparency/Seeing (1 worst - 5 best): 2/2
NELM: --
Conditions: The horizon was covered with a deck of low, thick clouds. The Sun set into it. Altitudes greater than 4
° presented a whitish background. Small thin clearing around 12° ~ 15° altitude.
Observing party: me
---------------------------------------------------

This photo shows the sky at sunset. One third in from the right along the horizon, two low buildings can be seen across the Hudson River. To the left of that is a small, mostly obscured reddish disk. That's the Sun. I watched it set into the clouds! Charlie and Kin each a saw similar event from different locations. None of us watched it together.



Here are the Takahashi binoculars set up with Lady Liberty in the background. (Liberty Cam here). Just after set up I took some peeks at the statue, passing boats & ferries, and the Staten Island shoreline. But this picture shows the bins ready for buisness with a Thousand Oaks solar filter attached to the right tube. I find great utility with rubber bands. Here the filter is slipped on to the tube with some filler in the rim to gain a more snug, centered fit and then rubber bands act as an insurance policy. Although, a filter wasn't necessary once the Sun sunk below 12° because the clouds were enough of a filter.



Like here, you can see how effective the sky was acting as a filter. Bright smudge.

The Baader solar filter hangs in the white shopping bag from the tripod. I used it for a brief period earlier but the Sun was not strong enough to observe through the filter


Behind me to my right the East Coast Memorial stands, at the rear is a lrage statue of an eagle that presides over eight granite slabs inscribed with the names of U.S. servicemen who died in the western Atlantic during World War II.


This young crescent Moon opportunity had all the elements for success. Elongation at sunset was 9°17' and increased as sunset deeper beneath our horizon. The altitude of the Moon at this time was 6°18'. I predicted a sighting window between 8:35PM ~ 8:45PM, an altitude ranging from 3°26' to 1°45', the Sun was -5°14' at the later time.
Also, just had the experience of seeing 0.8% illuminated crescent, so I was expecting the same impression but flipped horizontally. Actually I was expecting the crescent to be rotated slightly counterclockwise that the horns extend from 2:00 ~ 7:00~ish. (Yesterday's last crescent reached from 9:00 to 4:00.)

Trouble was that the weather didn't agree. It was clear in some parts but not in the area of interest. The photos show that well.

Charlie and I had been chatting during the day. We were to meet at the Seaman's Memorial but I am not familiar with lower Manhattan nor all the parks and landmarks around there. He sent me a google map which I ended up here. No problem, I set up any way flanked by fishermen to either side of me. The man to my right even cuaght a good size fish, had to be about a foot long as it flopped on the pavement until it could flop no more. I can't see eating any fish coming out of that river.

This promenade is pretty busy with people walking, relaxing on the benches, and sightseeing out across the river. Of all the people only 3 different couples actually stopped by. The most interesting was a family of three - sort of an attractive family, in their own way. Like most, curious Dad asked apologetically, "What the heck are you doing?" And I told him I was hunting for the crescent moon. I explained to all of them with a demonstration of my pencil, as the Moon, moving past and the stationary bins, as the Sun, describing the phases we see and when New Moon occurs. Mom, an attractive woman apparently not opposed to piercings, listened with no enthusiastic interest. She said, "And........So.........". A pause and I shrugged, "Okay."

"Oh, I get it. People need things to escape reality. He likes his motorcycles, I like to write, and she likes to to sing in the shower." I thought can't get any more real than our star standing naked eye before us as a day-glo orangy-red disc. The moon is somewhere around there. I handed the daughter, who had braces and as many pierces as her mom, the Baader film to have a look at the Sun. She couldn't see anything without putting her nose to the film. Oooooh, you're not supposed to do that, I wanted to say but smiled.

We chatted a bit more then they thanked me, wished me luck, and moved on. They were kind of cute.

Kin came by on his bike after the event was over. I set the bins on Jupiter to have a look at the planet and the arrangement of his moons: Callisto, Ganymede, Europa, and Io. After some time the little fisherman to my left walked up to the tripod and tried to look in. Even on tippy toes the top of his head didn't reach the eyepieces. He spoke no English but chuckled a lot. I lowered the bins to his height and he had a look. He was nodding and chuckling so I guess he enjoyed it. I was about to show him a picture in the Palm but he contuinued to nod and chuckle as he was walked over the fishermen on my right.

So what's next? We'll see. I have been trying to plan some time under dark sky not terribly far from NYC. But with this fickle weather it is hard to plan for in advance. Since this is New Moon time, dark skies are here, even if they are behind the haze and clouds.





Monday, July 24, 2006

kind like science

Saw this video the other day which reminds me of lab. Actually, one can find something similar, on a smaller scale, to these in science experiments or hobby books. Haven't we made things like this with Alka Seltzer and the bottle rocket?

And, as I recall, lab never had a sound track :^D

20060724 - |18.9| hour waning crescent Moon

Panels showing Moon at 5:02AM and details at last sighting of 5:34AM.

Session Name: 20060724.0410
--------------------------------------------------

Location: John Finley Walk, Carl Schurz Park, NYC
Site Classification: Urban
Date/time: 24 July 2006, 4:10AM ~ 7:15AM
Moonrise: 4:46AM
Sunrise: 5:45AM
Handheld Binos: Fujinon 7x50, fov 7.5°
Tripod-mounted Binos: Takahashi 22x60, fov - 2.1°
====================================

Weather History
Transparency/Seeing (1 worst - 5 best): 4
NELM: 5.0, in Perseus
Conditions: Clear with some thin clouds stretch from south-southwest towards the east. Otherwise, clear and crisp eleswhere, Alpha Perseid Association, Pleiades and Hyades clear to the naked eye.
Observing party: Charlie, and me
---------------------------------------------------

Back on 27 May 2006, I saw my youngest crescent moon to date, a 19 hour waxing crescent. This morning I got my oldest Moon, 28.73 day old waning crescent. In terms of absolute time from a New Moon that's 18h57m, three minutes besting my personal record.

The period from New Moon to New Moon is known as synodic month, or lunation, with a value of 29.53 days. Charlie asked if this was a constant which I am thinking it is but not too certain.

I arrived around 0415 with coffee in hand at our usual bench on the John Finley Walk, Carl Schurz Park. Surprisingly there were some people about the area. 2 women in workout clothes walked by briskly - I'd see them pass both ways. Another lone guy was leaning on the railing looking out over the river. At first I thought it was Charlie but it be another 10 minutes or so before he showed.

While it was still dark, I grabbed some looks at M31 and Pleiades. With what an urban sky offers, I admired the starfield in and around Perseus. The sky was clear straight up, thin veils of cloud banded across the sky about 45° in altitude from the south-southwest reaching towards the east. Venus was brilliant above the bridge, easily to be mistaken for hovering helicopter.

Not long after Charlie arrived, twilight was coming on fast, a steady march as it climbed to the height of the bridge in no time; advancing with no obstacles. The Manhattan horizon was not yet as reddish or orangy as some mornings could be. Though the Moon was nearly 9.5° elongated from the Sun, leaving us a bit of a comfort zone. Compare that with the May crescent where elongation was 10°14'. When we spotted the crescent then the Sun was 2°57' below the horizon (no corrections for refraction).


This is the before picture of Venus rising above the Triborough Bridge. Red lamps mark the top of the two bridge pilons. The lone red lamp to the left is about 3°29' in altitude.

To locate the Moon, I hopped from Venus to Castor and waited for Pollux to clear the brightening horizon. Haze was light. At 4:48AM I was still on Castor and then 5:00AM I found Pollux in the low horizon haze. It was attenuated but clearly visible in the Takahashi binoculars. Shortly after I panned the bins looking in a 3:30~ish direction and there was the crescent Moon, pretty bright in the bins just above the bridge span (roadway). It could have been as early as 5:01AM, however, I marked it as 5:02AM. The old crescent, about 150° of arc, rose from behind the Triborough Bridge, framed by its suspension wires. A fabulous sight and an exciting feeling.

I was surprised to see it as easily as I did and with so much contrast to the background sky. It was low at this sighting, a mere 1°29' in altitude. For 33 minutes I observed the Moon until I lost it after a field adjustment at 5:34AM. The prior adjustments I would lose the Moon for a bit, as if hitting a blind spot, until I was able to recover it in the field, but the last time I was unable to. I am thinking had I left it I could have watched it sail into the field stop a little longer.


A snipping from TheSky6 showing relative positions of objects used for starhopping.

As we observed it, Charlie and I were comparing our impressions aloud. He remarked that it was lumpy while I described it as having an pretty even crescent width until the reaching the horns. The last 15° ~ 30° near each it tapered off curving into the horn. In the bins I would say that this was an easy sight and we both agreed that there were bright patches/areas on the moon. To describe the orientation and length of the crescent in our field of view, we both agreed that it extended from 9 ~ 4 and the bright patches were seen in the areas of 5 o'clock, 6, and 7.

I regret not trying for naked eye. I was so excited about finding it and seeing it in the handheld bins, I didn't even stop to think of looking without optical aid. It became increasingly difficult to see the crescent in handheld Fujinon 7x50s. I would lose it long before I did in the Tak bins. The sky was brightening quickly as sunrise was getting closer.

In terms of absolute value from New Moon, this is the "youngest" that I have seen 18h57m, 4 minutes younger than the May young crescent. (4 because May's event was actually 19h01m). Illumination then was 0.9% whereas today it was 0.8%.

Only one woman passed and expressed interest at what Charlie and I were doing. At one point I lowered the tripod to allow her to look. After describing where to look she said she saw it. I am not quite sure she did because you know when pedestrians see something in the eyepiece, especially after they spend a moment or so looking but don't see. I could be wrong.

After the excitement we waited for the Sun to rise. Charlie brought his solar filters so we used his Canon 15x bins to see. We watched the Sun rise from behind a distant factory on the horizon. Later two sunspots were easily seen on the eastern side of the solar disk. This is sunspot 901 seen here at spaceweather.com.


This is the after shot of the Sun rising. Charlie let me snap some photos through his bins, inset shows solar disk silhoutted by antennae on the factory roof. The Triborough Bridge is the large one in the foreground. I don't know the name of the arched one behind.

I was packed up by 7AM though kept the Fujinon bins in hand. I had spotted Venus a couple times but couldn't get her naked eye. Charlie packed and un-packed his gear, attempting to see the ISS pass within a degree of Venus. As I futzed around with the computer, he mentioned that he didn't see it.

I was so impressed by how clear and azure blue the sky looked. After having some poor days and nights weatherwise, this was a godsend. Even walkng out of the park, I menetioned to Charlie how pretty the color composition of the green tree tops, red and off-white buildings and the blue sky. A perfect Monday morning.

Looking up: "Thank you"

Charlie's report can be found here.

Monday, July 17, 2006

20060717 - Epsilon Piscium occulted





This particular morning I found myself awakening in the living room about 1 in the morning. I picked myself up sluggishly and turned to the windows to draw the blinds. There was a 21.5 day moon, almost last quarter rising above the New York skyscraperscape. Out of curiousity, and partially habit, I took a peek through the bins. I was curious to see if libration was favorable to see Mare Orientale on the western limb.

Instead I saw a bright star which turned out to be Epsilon Psc, a magnitude 4.27 reddish star easily seen in the bins. It looked to be right in the path of the sailing Moon and in not too long of a time. I checked Starry Night and TheSky6 planetaria software. The star points are so big in these apps that it is difficult to get an accurate time of the occultation's disappearance and reappearance. I had the same problem with PftP.

So I set up the Tak bins onthe tripod and watched the event through the bedroom window. The occultation disappearance was on the Moon's bright side, a waning gibbous traveling east in teh sky. As the Moon approached the star, really, really close, it became difficult to see that star. I was able to see it nearly pimple up on the limb, but this was difficult. I would lose sight of the star and re-gain it after a moment. There came a time I couldn't recover it.

I estimate the disappearance between 01:25AM ~ :26AM. This disappearnace was not a blink out. Not acquiring it as quickly as I was able to early resulted in the estimated time. It was just too dificult as I looked through a window and it was on the bright side. I didn't see or notice any significant flare and was just as surprised not to have seen it. I didn't think I would have seen it so close.

This was a work night. Monday morning it was, the wee wee hours. I was still feeling tired even when noticing this but with the bad skies we've had this season I thought why not. So I set the alarm for 2:00AM and woke up.

The reappearance was entirely different. The light snapped on and the star was big and bright after escaped from behind the Moon's dark side. The reaapearance happened at 02:10AM.

Altogether it was worthwhile. More than the occultation and admiring a mysterious waning Moon, it reminded me of the Pleiades graze & occultations Team TotL observed from Staten Island earlier this year.

Mysterious waning Moon because I don't often observe in the early morning hours. I don't get much of a chance to do all nighters and it seems that the parks close at 1AM for us. The only spot that really caters to the rising last quarter and waning crescents Moon is Carl Schurz Park. In spite of not the most closest and convenient spot to reach, it definitely is a place I like to experience sunrise in New York.

peter

Friday, July 14, 2006

Time to move on


The weather hasn't been so great here so when the Sun began to shine I decided to look up. I continued with the manhattan henge sunset effect which was beter today. Holding a solar filter that I use with my Tak refractor, I was able to watch the Sun set into the building on the Jersey side of the Hudson River.

As described previously, the summer ecliptic lies more shallow than the spring ecliptic causing the Sun to move horizontally as well as vertically during its apparent descent. So this setting effect seen down the streets is not restricted to one specific day. It will occur for a few days to come. Since the 57th St. and 7th Ave. intersection is nearby my home, I snapped a couple of photos of the Sun setting into the building.


During sunset, unadulterated solar splash


Sunset behind the building that sits on the New Jersey shore.


Like "monkey see, monkey do", people saw me standing in the street snapping photos or walking away from having taken some and they would hold their cameras and point-n-shoot into the general direction that I was shooting. I was amused because a lot of people did this. Only a couple asked and they asked to look through the filter.

Since the escalations in the mideast with Israel, Lebanon, Syria and Iran, the police presence around Carnegie Hall increased. Thanfully the police didn't bat an eye when I run into the middle of the street to hold up this silly filter every time the traffic light changed. Anything goes in the city. The gothamist has a link to a youtube video that sort of reinforces this.

Lastly, I couldn't get enough of that burger flavor that I went back to Madison Sqaure Park for more. Since the weather was fine, the line three times as long as the night before. I gotta admit them Shake Shack burgers are damn good and worth the effort! As for the hot dogs, you won't be missing anything if you pass on them.


This had been sitting the drafts. If not anything else, some pictures of New York.




Thursday, July 13, 2006

Manhattan Henge - Weathered out

The pictures describe it best. Even though it rained and it was gloomy dark from the overcast clouds, at one point a red sunset streak broke thorugh the clouds above the horizon. But for the most part it was bust from this side of the clouds.


From the soutwest corner looking east into the intersection where people would have gathered.


Looking west down 34th Street. Base of the Empire State Bldg. on the right left side.


57th & 7th intersection, looking west. That monlithic structure in the middle sits on the New Jersey side of the river.



On the brighter side, I did grab two cheeseburgers & fries from Shake Shack. A lot of buzz about this "burger joint" (the name of another burger restaurant) that is notoriously known for the long, writhing line thorugh the Madison Square Park. This Shake Shack link even provides a webcam to see how long the line is.

If I had to choose between the two, I'd favor Shake Shack burgers - lighter, more flavorful, good bread. And then there is corner bistro's burger. There are other good spots around the city but these are certainly cheap-n-cheerful eats worth the trip at least once...and, you can get beer to wash them burgers down.

Wednesday, July 12, 2006

Practice Henge


Charlie, Kin, and I met up at 34th and Park for the second Manhattan-henge event of the year. Charlie had found two dates: 11 July from American Museum of Natural History and 12 July from Astronomy Picture of the Day (APOD). From the looks of this evening's turn out and that the Sun did not set between the buildings/street probably means that folks will turn out for it tonight on 12 July 2006. The hazy sky did not help but I thought that if the Sun did creep into that less-than-two-degree-corridor-between-the-buildings that it would be strong enough to punch through that crud. In fact, the haze could be a benefit to attenuate the Sun's brilliance for sharper photos and brief naked eye views.
While waiting, a few others showed up. John arrived with a video camera mounted on a monopod. He was going to shoot the event for a cable TV program. It turned out to be a practice run for him. A family of 3 showed up, as well. Dad had seen the Sun earlier in the day remarking that it was hardly seen. He was still optimistic that we might see something. Perhaps we'll see them again tonight. Although the event didn't happen the way we expected the meeting of this small group was just as enjoyable.


An empty intersection, looking south. Compare to this.


Back on 28 May, the last Henge event, the Sun set around azimuth 298°32'. This value was determined by using a value for the Sun's elevation at 0°28', and the angular size of the Sun is approximately 31'34".

On 11 July, at 8:20pm the Sun was 0°29' altitude with an azimuth of 299°09'. The Sun's angular size, according to Planetarium for the Palm, is 31'28".

On 12 July, at 8:20pm the Sun will be 0°25' altitude with an azimuth of 299°02'. The Sun's angular size remains unchanged at 31'28".
For both dates the ecliptic is almost 45°. Actually, May appears steeper with possibly a 60° incline as opposed to a 45° for July.

Given the azimuth values, the Sun will set slightly North, 30 arc minutes, which is nearly a solar diameter. From my point of view at 34th & Park, the street corridor is slightly less than my forefinger extended at arm's length. A finger width is estimated to be 2°. I haven't calibrated that measurement to be any more exact ;^D but my guess is that the angular measurement of the street to 1° 45'. That measurement yields a street corridor measurement in terms of solar diameters to be ~3 ½.
This evening we didn't even see a hint of the Sun but it should have passed through our field of view. Unless I missed something the Sun set south of the street opening. Weather conditions don't look promising for tonight but will probably go and check it out to see if a crowd turns out.

peter

Saturday, July 08, 2006

Relative sizes - and TED presenters

Browsing the web for work related info, I discovered this illustrative tidbit mentioned at information aesthetics. I'm pretty sure we all know the planets of our solar system and how they stack up relative to their size, but a picture can be worth a thousand words.

(Artefacts seen on the illustrations are noted in the comments section at information aesthetics.)



======= skip -----------


If you're interested check out this effective presentation of Hans Rosling at TED. I really like how the data is illustrated over time where the trends become obvious (assuming the integrity of the source data is valid and accurate.) And Mr. Rosling is engaging as a presenter.

Mr. Rosling presentation content successfully demonstrates ideas he writes of in a paper,
Free software for a world in motion 2004, found at gapminder:

"Data in spreadsheets are meaningless to most people. Many statisticians are like musicians standing up in front of the audience showing the sheet music instead of playing it. We believe the number of users of international development data could multiply by millions if the data was distributed as interactive explorative customized graphic interfaces..."



While at TED, check out the other presenters. I liked the Sir Ken Robinson's on the importance of creativity in education. He used a good mixture of verbal bullet points and anectdotes to present a strong, structured argument. I also liked the beginning of Al Gore's presentation. He really engages the audience with his anecdotal style, however when he got to the heart of his presentation though I gotta admit he lost me. The PowerPoints slides keep him really tied to his message with not much range from the written words.