Thursday, April 03, 2008

What is the 'earth'?

Elisabeth asked a question about geography recently, and I began by answering, "We live on planet earth . . ."
She quickly interrupted me, "What is the earth?"
I explained that the earth is the planet on which we live.
She stopped me again, "What is a planet?"
I said, "It is shaped like a ball."
"Where we live is like a rectangle [meaning flat], not a ball!" she retorted.
Apparently I'm going to have to pull out the simple activities through which we see evidence that the earth is, in fact, a sphere. I love teaching science!

5 comments:

Dylan said...

Care to post one or two of those?

Graham said...

The two simplest are the use of magnification, and elevation. If you use a telescope, pointed at the horizon, you cannot see more distant objects. You can only so the objects on the horizon at greater magnification. Elevation, however, allows you to see more distant objects (with or without magnification).

megfeen said...

She's probably a little too young for this, but I enjoyed it and you might too! Amazing to think about proportions in this way.

http://i51.photobucket.com/albums/f351/dabears1020/1202609635165.gif

It takes a little time for the images to go through.

megfeen said...

Did that show up?

http://i51.photobucket.com/albums/f351/
dabears1020/
1202609635165.gif

Graham said...

That is a remarkable photo show. Thanks!

Have you walked around the Hayden Sphere at the Museum of Natural History? It does an excellent job (in a similar manner) of giving a sense of scale.