Astronomy
Stellar Occultations: Measuring Minor Planet Shapes
Quick fact
A single well-observed occultation can measure a minor planet's diameter to within a few kilometers, even when the object is over 1 billion kilometers away – an accuracy that rivaled early spacecraft flybys.
Why this is interesting
Imagine a tiny asteroid hundreds of millions of kilometers away casting a shadow that, for a few seconds, blocks a star's light – and from that fleeting flicker, we can map its shape like a cosmic fingerprint.