Would teh horizon on the moon appear closer than one on earth? Or is the difference barely noticeable? Can you see the curvature of the moon more than you can on earth?
In other words, does it really feel like you’re standing on a smaller ball of rock?
No. A bit of simple geometry, combined with readily accessible data regarding the size of the moon will convince you of this easily. 
Well, what if you’re 100 feet tall, like me?
A hundred feet? Well, you must bear in mind that your feet weigh less on the moon, especially if you have bear feet. So instead of 100 feet, you have 16.666, which isn’t enough for a first down. The first down was Neil Armstrong, of course, who took a giant leap which led from the Eagle’s touching down. This was considered quite a feet for the time and is not to be confused with Fran Tarkenton, who took the Vikings to Mars.
And that, dear reader, is how the elephant got his trunk.
Wait, what was the question again?
decaf, Fish, decaf 
ok, Diameter of the moon is 3476km
Diameter of the earth: 12,756km
So a 1.5 meter tall person on the moon would have essentially the same view as a 5.5 meter tall person on earth. Does the earth noticeably curve if you stand on top of your house?
http://images.ksc.nasa.gov/photos/1969/medium/AS11-44-6549.jpg
Doesn’t prove anything, but it’s a fantastic pic.
One of the things that all the moonwalkers said upon returning to Earth was that it was very hard to judge distance on the Moon. Something that looked like it was 50 yards away would turn out to be 100 yards away. IIRC, NASA decided that it was the lack of atmosphere causing the illusion. Doesn’t directly answer your question, but perhaps points you in the right direction.
I suspect that the lack of landmarks had a lot to do with that, too. In the picture that A.R. Cane linked to, it looks like the surface of the Moon is pretty much empty and featureless. Atmosphere or not, I’d have a pretty hard time judging how far away something was in a place like that.
Yeah, you’re right, and given that the kind of landscape they were seeing was totally unfamilar to them, their brains might have had a little trouble sorting it all out.
See, that’s why I asked. On the face of it I wouldn’t have expected a noticeable curvature, but pics like that make me think perhaps my logic is flawed.
I guess they used a distorted wide angle lens or something up there.
Fantastic as it is, that shot’s from orbit; captioned A view of Earth as the Apollo 11 Command Module nears the surface of the Moon
Deserts give much the same illusion. Clear air and a relatively featureless landscape can result in a mountain 100 miles away looking like it’s not far outside of town.
Waitaminnit! You can see the stars! That means the photo isn’t real, and it PROVES that the moon landings were faked in a studio in Schenectady in 1957 by a cabal of left-handed Russian cinematographers who had been smoking fermented squirrel droppings!
Or something.
You’d be surprised how adapted your eyes are to the Earth. The lack of the atmosphere on the moon means that objects don’t really get blurry as they get farther away. You depend a lot on this blurriness to determine distance.
I believe Phil’s Bad Astronomy website talks about this when debunking the Moon Landing Hoax Theory.
For a six-foot-tall observer, the Earth’s horizon is about 2.6 arcminutes below “horizonal” due to the curvature of the Earth; on the moon, it goes up to about 5 arcminutes. Given that the visual acuity of the human eye is about one arcminute, this would be distinguishable in principle — but then, you wouldn’t have the two horizons to compare if you were up there standing on the moon. It would be not unlike trying to distinguish between someone who’s 5’10" and someone who’s 5’10.1" without having them stand next to each other.
If you want to learn how to calculate the distance to the horizon for any spherical object and any distance above it, see
For kicks I put the formula into an Excel spreadsheet and compared a bunch of heights above the earth.
My guess is that your own height above the average radius of the sphere would have to be way high for you to notice more curvature than on earth.