Analog models of gravity

Okay, let's say you have a big rubber sheet, like the kind you might put on your bed. Imagine that this rubber sheet represents space.

Now let's imagine that you have a very heavy ball, like a bowling ball, that you put in the middle of the rubber sheet. What do you think will happen?

The rubber sheet will stretch down and the area around the ball will be lower than the rest of the sheet. This is kind of like how planets and stars bend space around them because of their gravity.

Now, if you take a smaller ball, like a tennis ball, and roll it around the big bowling ball, what do you think will happen?

The tennis ball will roll around the bowling ball and fall towards it because the rubber sheet is curved around the big ball. This is kind of like how planets orbit around stars because of gravity.

Scientists use models like this to help them understand how gravity works in space. It's not a perfect model because there are many other factors that come into play, but it can help scientists make predictions and test ideas about gravity.