Gravity: A heavy topic!
Today, we talked about how strange and interesting gravity is. We know so much about gravity already, but there is so much we still need to learn. What scientists have learned about gravity has allowed us to travel into space and to the Moon. It’s allowed us to send probes out into the solar system and beyond, and even to the surface of other planets, including Venus and Mars!
We learned that gravity depends on the mass of an object, and that all objects have some amount of gravitational force. Students moved through a series of stations where they modeled different aspects of gravity. They used magnets to show that the closer two objects are to each other, the greater the attractive force of gravity between them. They also compared the weight of an empty bottle with other bottles that weighed as much as the empty bottle would weigh if it were on the moon, Jupiter, or the Sun. The bottle filled with sand is what the empty bottle would feel like on the Sun, where it would weigh more than 27 times as much as it weighs on Earth!
Students then demonstrated how massive objects bend the fabric of space-time (using spheres of different masses, and a large piece of fabric). This bending of space-time causes other objects to gravitate towards massive objects. With just the right velocity and trajectory, a smaller object can go into orbit around a larger object…but if the smaller object is moving too slowly, it can fall and crash into that larger object. It’s a good thing the Earth doesn’t slow down in frictionless space, or it could crash into the Sun! Gravity is obviously important for astronomers and cosmologists to understand.