Wednesday, June 18, 2008

Solstice Moon Illusion


"June 16 , 2008: Sometimes you just can't believe your eyes. This week is one of those times.

"On Wednesday night, June 18th, step outside at sunset and look around. You'll see a giant form rising in the east. At first glance it looks like the full Moon. It has craters and seas and the face of a man, but this 'moon' is strangely inflated. It's huge!

"You've just experienced the Moon Illusion."

The story: http://science.nasa.gov/headlines/y2008/16jun_moonillusion.htm

Did I beat hale-bopp in posting this? Woo-hoo!

10 comments:

kkdither said...

Kudos, you did beat hale-bopp! I don't know if my pea brain can conceptualize the reason for this to occur, but you can bet your buns I'll be out gawking at it. Thanks for the literal heads-up! Wow, so cool...

OrbsCorbs said...

I don't understand the technical stuff, either, but I've seen this before over Lake Michigan. I grew up a block from the lake, and I'm a block away now. It's astounding! It actually scared me as a kid.

I, too, will be out there trying to get some pics tonight, but, like the other technical stuff, my camera is too much machine for me. I know it's capable of taking fantastic shots in low light, but I only know how to point and click. Maybe I'll drag out the instruction manual and tripod . . .

kkdither said...

If I was reading correct, and truthfully, I kinda scanned it, it said that the movie cameras show it as regular size, only our eyes process the bigness...Your camera might not give it justice?

OrbsCorbs said...

You're right.

"At first, astronomers thought the atmosphere must be magnifying the Moon near the horizon, but cameras showed that is not the case. Moons on film are the same size regardless of elevation: example. Apparently, only human beings see giant moons."

I don't know if I'm relieved because I don't have to mess with the camera, or disappointed because I can't get a pic of it. But isn't that a pic in the story? I guess it isn't as big as the "illusion."

kkdither said...

Stop making me think so hard, my head is hurting. lol

hale, where are you to clear this up for us? Besides, pictures in your head (memories) are always better than anything you can catch on film...

drewzepmeister said...

Thanks for the heads up Orbs! I only live a few blocks away from the lake myself.I'll head down there,also to take some pictures. At least,I'll give a shot.:)

hale-bopp said...

Yep, I was off-site this morning so I am easy to beat to the punch today.

The article does a good job of summing up some of the various ideas on why we see this illusion. No one is 100% sure yet. I have also noticed that constellations such as Orion appear larger near the horizon as well.

You can do the digital camera experiment...take a pic of the Moon on the horizon and then again a few hours later. Use your computer to measure the Moon's diameter in pixels and see that it has not changed. For the low tech version, just hold out a finger at arms length and compare the size of the Moon to your finger when it rises and then a few hours later. Again, you will see the size of the Moon is unchanged.

Another personal observation is that I find the illusion more pronounced when the Moon is rising over the Rincon Mountains in the east. It is difficult to judge the distance to the mountains (they are always farther away than they look) and that seems to strengthen the illusion for me.

OrbsCorbs said...

I went out there at 9 and got some pics of the moon, but no tripod so I'm sure they're blurry. I hung around for about half an hour and the moon rose, and it was very pretty and orange and glowing off of the lake, but it wasn't particularly huge looking. I went back out a little after ten to see it higher in the sky, and, again, pretty and large, but not huge. The one I remember from childhood was while riding in my parents' car headed east on Goold St. As we approached the lake, the moon looked enormous, wider than the road, like someone had moved it thousands of miles closer to earth. I thought maybe aliens had something to do with it.

kkdither said...

I took a drive down there too. Cars were lined up, many people out taking pictures. Cool, how many readers do we have? : )

Yes, beautiful, orange, full, trail of reflection on the lake, but not especially big.

One time, just recently, I saw it setting in the early morning in the western sky. It was amazingly huge. It looked even bigger than the picture here. I had high hopes last night. Oh well....

drewzepmeister said...

My son and I walked the dog to Shoop Park last night to see this. The moon wasn't as large as I expected it to be. Nevertheless,it was huge,orange,and beautiful. I could have sat there on the pier for hours-watching the reflection.

I took several pictures,without a tripod,most of them came out blurry and out of focus. The good news is-a couple of them actually turned out half way decent.