stackyFACTS
Science

Jupiter's moon Io helped reveal the speed of light

HERE’S THE INTERESTING PART

In the late seventeenth century, astronomer Ole Rømer noticed that the eclipses of Jupiter's moon Io seemed to occur later when Earth was further away in its orbit. He correctly deduced that light was not instantaneous, using this orbital delay to calculate the speed of light for the first time in history.

Jupiter's moon Io helped reveal the speed of light
STACKY / Science
One discovery leads to another.

Keep exploring facts in this topic.

Science →
STACKY FOR IPHONE

A bigger world.
One discovery
at a time.

Keep discovering with Stacky. Interesting facts in an app that is always within reach.

Download on the App Store
ONE MORE DISCOVERY?

Keep exploring

All in this topic →
StackyMore discoveries in the app
Download on the App Store