Fun fact: the Hubble Space Telescope has observed and photographed every planet in the Solar System except Mercury. Mercury’s just too close to the Sun. I’m sure you know what a magnifying glass can do to ants, so imagine what would happen if we pointed Hubble—with all its oversized lenses and mirrors—in a sunward direction.
So does that mean Hubble has photographed Earth? The answer is yes, sort of.
A Hubble image of Earth would not look like this. Hubble orbits at a distance of only 550 kilometers (340 miles). That’s too close, so the image would look more like this.
No, that’s still not close enough. Also, Hubble is moving at a velocity of over 25,000 kilometers per hour (16,000 miles per hour). So our snapshot of Earth turns out something like this.
But that doesn’t stop Hubble from snapping blurry photos of Earth anyway. Believe it or not, they’re useful to scientists. As the always brilliant Phil Plait explains (click here), the Hubble team uses these pictures, called flat-field images, to test and calibrate Hubble’s cameras.