Doesn't it depend on your eye level and height? I thought the answer was about 4 or 5 miles on a clear day, but fog & rain could limit that too. Is there really a definitive answer? I mean, the sky & the sun don't really meet, so shouldn't the answer to a hypothetical be hypothetical? LOL   Once I was on a boat and we were pondering this. Since I can't swim (not too well) I suddenly got nervous and said "Who cares? I just hope you know how to get back home." LOL

Thanx Justxploring. It is kind of trivial, but this guy at work thinks he knows everything. Anyway, i just came back from wikepedia, and it turns out we were both wrong. At a height of about 5 to 6 feet tall at sea level, it's about 4.7 kilometers which is just over 3 miles.

I thought the source i had years ago was good but I guess not...lol

But Wiki is written by people just like us, right?   Anyway, this is an explanation that's not too hard to understand. It says 3.5 miles, so that's pretty close to 3. (But I said 4 or 5 and 4 is only .5 more 3.5! :-)   I always really thought the weather (like the clouds) had something to do with it too. "On a clear day...." But at this point in my life, I'm thankful to find my car at Publix without using my panic button.

Who's on first?

Oops - said this is a simple explanation and then forgot the link

http://www.boatsafe.com/kids/distance.htm

I saw that link first and didn't believe it. But it was right.
How far is it from publix parking lot to the front door...lol

Well, let's see. That depends on how many people you run into sitting on the bench outside. Then there are the cars you need to dodge and the shopping carts. :-)

You forgot the girl scout cookie sale event that seemsa to be perpetuating ever so longer every year...lol

Here ya go pac

http://scubageek.com/articles/wwwhorizon.html

Thanx four4me.