Reducing the whole Earth to a single spot of light. That’s the goal of planetary researcher Daphne Stamm. With her colleagues, she wants to make a very small measuring instrument, about the size of a milk carton, that can look at Earth from the Moon. And what this device sees next must be reduced to a single point. Earth footprint.
why? “We now know that every star in the sky has planets,” Stamm says. “But we don’t know yet what they look like.” “So we want to measure that footprint of Earth, because we’re only going to see one point of planets around other stars. And we don’t know what those planets look like, so you have to get that from that one point.”
From oceans to feather grasses
So that’s the ultimate goal of this Earth footprint: to discover new worlds elsewhere in our universe. It’s amazing how much information such a small spot of light can hold. For example, you can tell if there’s oxygen in a planet’s atmosphere, says Stamm, “because oxygen molecules absorb certain colors of sunlight — so they’re not reflected back into space.”
The same applies to grass, foliage, deserts, oceans and clouds. They all reflect part of the light in a unique way, while absorbing another part. “If you look at the Earth from billions of miles away, the Earth is only one speck of light. But it contains all the reflected sunlight. It is reflected in the atmosphere, clouds and ivy leaves. We want to know what the Earth would look like.”
To the moon, please
Presenter Petra Grays together again at the end of the podcast: “By looking at ourselves, we can look better at other planets and stars.” She could almost turn it into a metaphor: only when you take a good look at yourself for the first time can you really get to know the other. By reducing ourselves to one basic spot, we might find extraterrestrial life. Now this is the only way to get moon milk.
