APOD: Full Moonrise (2012 May 05)

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Expand view Topic review: APOD: Full Moonrise (2012 May 05)

Re: APOD: Full Moonrise (2012 May 05)

by neufer » Tue May 08, 2012 1:54 pm

joelwellwater wrote:
The moon had a big effect at the beach, it was really high tide with huge waves. We really scared that time, but we amaze and watch the moon. It was a big WOW!, it was huge. I wonder if what are the werewolves doing that time XD :)
The moon is ~2.4 denser than the sun so lunar quadrupole tidal effects are nominally ~2.4 stronger.

(The volume of similar apparent sized objects goes as the cube of their distance;
whereas, the quadrupole forcing goes as the inverse cube of their distance.
Hence, the relative quadrupole forcing of the sun & moon only depends upon their relative densities.)

The moon is ~7% closer than normal so it's quadrupole tidal effects are ~ 22% stronger (i.e., 1.073).

So the total tidal effects of a full perigee moon are ~ ( 1 + 2.4 x 1.22 )/2.4 ~ 64% stronger than normal.

However, the maximal "spring" tides should follow the maximal forcing event by 2 to 3 days:
http://en.wikipedia.org/wiki/Tide wrote:
[img3="maximal "spring" tides should follow the maximal forcing event by 2 to 3 days"]http://upload.wikimedia.org/wikipedia/c ... ic.svg.png[/img3]
<<The semi-diurnal range (the difference in height between high and low waters over about half a day) varies in a two-week cycle. Approximately twice a month, around new moon and full moon when the Sun, Moon and Earth form a line (a condition known as syzygy) the tidal force due to the sun reinforces that due to the Moon. The tide's range is then at its maximum: this is called the spring tide, or just springs. It is not named after the season but, like that word, derives from the meaning "jump, burst forth, rise", as in a natural spring.

When the Moon is at first quarter or third quarter, the sun and Moon are separated by 90° when viewed from the Earth, and the solar tidal force partially cancels the Moon's. At these points in the lunar cycle, the tide's range is at its minimum: this is called the neap tide, or neaps (a word of uncertain origin).

Spring tides result in high waters that are higher than average, low waters that are lower than average, 'slack water' time that is shorter than average and stronger tidal currents than average. Neaps result in less extreme tidal conditions. There is about a seven-day interval between springs and neaps.>>

Re: APOD: Full Moonrise (2012 May 05)

by joelwellwater » Tue May 08, 2012 5:22 am

The moon had a big effect at the beach, it was really high tide with huge waves. We really scared that time, but we amaze and watch the moon. It was a big WOW!, it was huge. I wonder if what are the werewolves doing that time XD :)

Re: APOD: Full Moonrise (2012 May 05)

by wanna_be » Tue May 08, 2012 4:09 am

geckzilla wrote:I think you're taking it a little too far, now. I'm going to lean on good old Occam and his nifty little razor and say the photographer is responsible for the entire content of the photos and it isn't as complicated as you are making it out. It's several photos stitched together to create a vertical panorama.
That's a perfectly reasonable project, but if approached in a scientific way, it would produce a coherent and understandable result with some kind of smooth mapping to accommodate the changing view direction from the very near to the distant. I would expect that the center line, corresponding to points in line with the moon from the camera POV, would be preserved. I don't see why that's too much to expect from the Astronomy Picture of the Day. The photographer says on his website first that he is, "an astronomer, photographer, and mathematician", and then that his technique aims "to give a representation of what a person could experience if they were there at the time." So I don't think my expectations are out of line.

Re: APOD: Full Moonrise (2012 May 05)

by geckzilla » Tue May 08, 2012 2:51 am

I think you're taking it a little too far, now. I'm going to lean on good old Occam and his nifty little razor and say the photographer is responsible for the entire content of the photos and it isn't as complicated as you are making it out. It's several photos stitched together to create a vertical panorama.

Re: APOD: Full Moonrise (2012 May 05)

by wanna_be » Tue May 08, 2012 2:37 am

geckzilla wrote:Gonna say this is a battle not worth picking. It's meant to be artistic, not scientific.
It's not a battle, it's a question. What did he do? How far did he go? I mean once you start cutting and pasting, where do you stop? Where is that water tower? Did he pick it up from an image archive? Would that be cool? Enquiring minds want to know!

Re: APOD: Full Moonrise (2012 May 05)

by geckzilla » Tue May 08, 2012 12:35 am

Gonna say this is a battle not worth picking. It's meant to be artistic, not scientific.

Re: APOD: Full Moonrise (2012 May 05)

by wanna_be » Tue May 08, 2012 12:22 am

After following up on my "ground track", I'm back to big problems with this image. That is, I don't think it is scientifically coherent. I identified the houses in the foreground and found that a line of sight towards the moon gave a bearing of 120 degrees, using the Google Earth line drawing feature. The correct bearing would be 112.5 degrees, according to my Starry Night software. Then if I follow this line of sight, I run into inconsistencies for some of the identifiable buildings. That is, they don't fall to the correct side of the line. I noticed too, that the building images seem to be vertically compressed. There are some buildings on the middle left that look like the Colorado State campus, but this is way out of line. Then when I get beyond the middle ground, I'm at a complete loss. I'd love to know where that water tower is! I can't find any candidate for it, even doing a "ground search" with Google Street View in various areas. If anybody can figure this out, I'd love to hear about it.

Re: APOD: Full Moonrise (2012 May 05)

by nstahl » Mon May 07, 2012 1:18 pm

It is certainly a striking picture taken with either a lot of luck or some good planning. Short on astronomical knowledge but timely and fun to see. Good APOD.

Re: APOD: Full Moonrise (2012 May 05)

by cleanwaterstore » Mon May 07, 2012 8:46 am

Sad to say that we haven't saw the biggest moon ever for the year of 2012. The clouds were very thick, and we were preparing if ever the water level at the beach would rise. I saw the moon in the video online, and all I can say is.. WOW! that was huge!

Re: APOD: Full Moonrise (2012 May 05)

by wanna_be » Mon May 07, 2012 3:13 am

OK, hold everything! I've located the "ground track" in Google Earth, and I'm up to Warren Lake. It's direction checks out with the ESE bearing of the rising moon at that date and location. My estimate of the distance to that water tower may turn out to be pretty close. I guess what was really bothering me was that I just couldn't get oriented.

Re: APOD: Full Moonrise (2012 May 05)

by wanna_be » Mon May 07, 2012 1:57 am

Everything in the picture is calibrated by the angular size of the moon. For example, the water tower on the horizon is about 1/14 the diameter of the moon, in the image. This means it subtends about .01/14 radians, and this is the ratio of its height to its distance from the camera. A 100 ft height puts it about 26 miles away, by my calculation, and this seems unreasonable. ( This is a below average height for this type of water tower according to WIki references. )

Re: APOD: Full Moonrise (2012 May 05)

by Chris Peterson » Mon May 07, 2012 1:44 am

wanna_be wrote:I will venture to say that the moon is way too big for the scene, based on simple considerations using the 1/2 degree size of the lunar disk.
How do you figure? I don't see anything in the foreground scene that gives even a hint of an angular reference.

Re: APOD: Full Moonrise (2012 May 05)

by geckzilla » Mon May 07, 2012 1:16 am

wanna_be:
While I can't say for certain that the moon hasn't been resized, I would wager that only curves and saturation have been selectively altered. It's easy enough to get the moon looking that large with a single telephoto exposure without having to resort to dubious methods. I think the photo is a good photo but I personally would have preferred it to be a little less obviously processed. As with any artistic endeavor, there are bound to be people who disagree with the outcome. I've seen plenty of moon photos where the moon is this bright yellow color though so maybe it's something else causing it to not look "right" to me. The shearing you've noticed on some of the objects was most likely caused by putting multiple exposures together to form a much wider angle image, since a telephoto lens would never capture the entire landscape all at once. I enjoy that aspect of it a lot and I appreciate the work that went into it. It's just something strange with the colors.

Re: APOD: Full Moonrise (2012 May 05)

by wanna_be » Sun May 06, 2012 11:34 pm

geckzilla wrote:Some strange processing on this makes the moon look incredibly saturated. It's kind of like looking at famous faces on magazine covers who have received Photoshop makeovers... something isn't quite right but you can't be sure what it is.
There are a lot of things wrong with this picture. On the photographer's site, he states upfront that "most of his work" is made with composites and is highly processed. In fact, there is a "tell" in the hi-res image. In the middle ground there is a line of power poles with single sided cross bars. One of them left of center is "chopped in half" so that the top portion is "hanging in the air". I'm still working on trying to place some of the landmark structures that can be seen, but I haven't had any success so far. I will venture to say that the moon is way too big for the scene, based on simple considerations using the 1/2 degree size of the lunar disk.

Re: APOD: Full Moonrise (2012 May 05)

by neufer » Sun May 06, 2012 6:34 pm

Click to play embedded YouTube video.
.
bystander wrote: Dropping a dime on the Moon
Discover Blogs | Bad Astronomy | 2012 May 05
... How far away would you have to hold the dime so that it appears as big as the Moon to you? ...

Re: APOD: Full Moonrise (2012 May 05)

by bystander » Sat May 05, 2012 7:33 pm

Dropping a dime on the Moon
Discover Blogs | Bad Astronomy | 2012 May 05
... How far away would you have to hold the dime so that it appears as big as the Moon to you? ...

Re: APOD: Full Moonrise (2012 May 05)

by hotboy18 » Sat May 05, 2012 5:46 pm

Full moon for Cinco De Mayo?

Re: APOD: Full Moonrise (2012 May 05)

by neufer » Sat May 05, 2012 5:31 pm

http://en.wikipedia.org/wiki/Rachmaninoff wrote:
<<Rachmaninoff's First Symphony (Op. 13, 1896) was premièred on 28 March 1897 in one of a long-running series of "Russian Symphony Concerts", but was brutally panned by critic and nationalist composer César Cui who likened it to a depiction of the ten plagues of Egypt, suggesting it would be admired by the "inmates" of a music conservatory in hell. The deficiencies of the performance, conducted by Alexander Glazunov Glazunov, who was by all accounts an alcoholic and may have been drunk, were not commented on.
After the poor reception of his First Symphony, Rachmaninoff fell into a period of deep depression that lasted three years, during which he wrote almost nothing. He became engaged to fellow pianist Natalia Satina whom he had known since childhood and who was his first cousin. The Russian Orthodox Church and the girl's parents both opposed their marriage and this thwarting of their plans only deepened Rachmaninoff's depression.

In January 1900, Rachmaninoff was invited to Yasnaya Polyana, the home of writer Leo Tolstoy, whom Rachmaninoff greatly admired. That evening, Rachmaninoff played one of his compositions, then accompanied Chaliapin in his song "Fate", one of the pieces he had written after his First Symphony. At the end of the performance, Tolstoy took the composer aside and asked, "Is such music needed by anyone? I must tell you how I dislike it all. Beethoven is nonsense, Pushkin and Lermontov also." (The song "Fate" is based on the two opening measures of Beethoven's Fifth Symphony.) As his guests were leaving, Tolstoy said, "Forgive me if I've hurt you by my comments," and Rachmaninoff graciously replied, "How could I be hurt on my own account, if I was not hurt on Beethoven's?" but the criticism of the great author stung nevertheless.

In the same year, Rachmaninoff began a course of autosuggestive therapy with psychologist Nikolai Dahl, who was himself an excellent though amateur musician. Rachmaninoff began to recover his confidence and eventually he was able to overcome his writer's block. In 1901 he completed his Piano Concerto No. 2 in C minor, Op. 18 and dedicated it to Dr. Dahl. The piece was enthusiastically received at its premiere at which Rachmaninoff was soloist and has since become one of the most popular and frequently played concertos in the repertoire. Rachmaninoff's spirits were further bolstered when, after three years of engagement, he was finally allowed to marry his beloved Natalia. They were wed in a suburb of Moscow by an army priest on 29 April 1902. using the family's military background to circumvent the church. The marriage was a happy one, producing two daughters - Irina, later Princess Wolkonsky (1903-1969) and Tatiana Conus (1907-1961).>>

Re: APOD: Full Moonrise (2012 May 05)

by Mr. Mooney » Sat May 05, 2012 3:41 pm

Re: APOD: Full Moonrise (2012 May 05)

by Sam » Sat May 05, 2012 3:07 pm

neufer wrote:
Click to play embedded YouTube video.
1:49 & 5:52, but the best is at 9:13 and following:
Click to play embedded YouTube video.

Re: APOD: Full Moonrise (2012 May 05)

by geckzilla » Sat May 05, 2012 1:50 pm

Some strange processing on this makes the moon look incredibly saturated. It's kind of like looking at famous faces on magazine covers who have received Photoshop makeovers... something isn't quite right but you can't be sure what it is.

Re: APOD: Full Moonrise (2012 May 05)

by Boomer12k » Sat May 05, 2012 5:31 am

It's the Energizer Bunny...

:---[===] *

Re: APOD: Full Moonrise (2012 May 05)

by neufer » Sat May 05, 2012 4:23 am

Click to play embedded YouTube video.

APOD: Full Moonrise (2012 May 05)

by APOD Robot » Sat May 05, 2012 4:06 am

Image Full Moonrise

Explanation: Rising as the Sun sets, tonight's Full Moon could be hard to miss. Remarkably, its exact full phase (May 6 03:36 UT) will occur less than two minutes after it reaches perigee, the closest point to Earth in the Moon's orbit, making it the largest Full Moon of 2012. The Full Perigee Moon will appear to be some 14 percent larger and 30 percent brighter than a Full Moon near apogee, the most distant point in the elliptical lunar orbit. In comparison, though, it will appear less than 1 percent larger and almost as bright as April's Full Moon, captured in this telephoto image rising over suburban Fort Collins, Colorado, USA. For that lunation, Full Moon and perigee were about 21 hours apart. Of course, if you manage to miss May's Full Perigee Moon, make a note on your calendar. Your next chance to see a Full Moon close to perigee, will be next year on June 23.

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