Astronomy Picture of the Day

Explanation: Today's solstice marks the northernmost point of the Sun's annual motion through planet Earth's sky and the astronomical beginning of the northern hemisphere's summer. But only two days ago, the Full Moon nearest the solstice rose close to the ecliptic plane opposite the Sun, near its southernmost point for the year. Astronomer Anthony Ayiomamitis recorded this dramatic picture of the solstice Full Moon rising above Cape Sounion, Greece. The twenty-four hundred year old Temple of Poseidon lies in the foreground, also visible to sailors on the Aegean Sea. In this well-planned single exposure, a telescopic lens makes the Moon loom large, but even without optical aid casual skygazers often find the Full Moon looking astonishingly large when seen near the horizon. That powerful visual effect is known as the Moon Illusion.

Fabulous!

I was driving in the north-western Wisconsin bluffs along the Mississippi River early one evening during an August Summer and the Moon was doing this. I had to pull over and watch it because it was so incredible and I knew I’d most likely never see it again in my lifetime.

It looked as if you could just reach up and touch the Moon, it seemed that close! And blood-orange in color.

We live on the Best. Planet. Ever. :)

Inconstant Moon
The Moon at Perigee and Apogee
http://www.fourmilab.ch/earthview/moon_ap_per.html

[snip] The Moon’s orbit around the Earth is elliptical, with a substantial eccentricity (as major Solar System bodies go) of 5.49%. In addition, the tidal effect of the Sun’s gravitational field increases the eccentricity when the orbit’s major axis is aligned with the Sun-Earth vector or, in other words, the Moon is full or new. [end]

Lunar Perigee and Apogee Calculator
http://www.fourmilab.ch/earthview/pacalc.html

Lunacy at large
What makes a solstice moon look so huge?
Jun 20th 2008
http://www.economist.com/daily/columns/techview/displayStory.cfm?story_id=11604080

[snip] Ponzo’s illusion implies that the moon appears larger when close to the horizon because we perceive it as being further away: objects in the foreground (trees, houses) act like Ponzo’s converging railway lines... Unfortunately, pilots flying at very high altitudes also report seeing the moon illusion. If the Ponzo explanation is correct, they shouldn’t. There are no trees and houses nearby to create the measure of scale needed for the illusion to work... psychologists continue to bicker over whether the illusion results from some “apparent distance” effect like the Ponzo and flattened-dome explanations, or whether a “relative size” hypothesis is at work. [end]

See a Huge Moon Illusion Wednesday
space.com | June 18, 2008 | Robert Roy Britt
Posted on 06/18/2008 2:49:28 PM PDT by lainie
http://www.freerepublic.com/focus/f-news/2033002/posts

http://science.nasa.gov/newhome/headlines/ast19dec99_1.htm

[snip] At perigee, the Moon’s closest approach, the Moon is 50 thousand km nearer to us than it is at apogee, its greatest distance. When the Moon is closest... it appears to be a whopping 14% larger than its minimum size at apogee. [end]

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