On this night in science
Einstein's new idea about gravity
November 25, 1915
On this day in 1915, Albert Einstein presented the final version of his equations for gravity to scientists in Berlin. They described gravity in a new way: heavy things like the sun bend space and time around them, and other things follow those curves.
Why it mattered
His equations solved a small puzzle about Mercury's path around the sun that no one had been able to explain. Scientists still use them to understand black holes and the bending of starlight.
Wonder together
If space can bend, what do you think would happen to a marble rolling across it?