Observatoire des droits humains (anglais seulement)

Curious Kids: is it possible to see what is happening in distant solar systems now?

(Version anglaise seulement)

par Jacco van Loon, Astronomer, Keele University

If a distant solar system is millions of light years away and so we see it as it was millions of years ago, how can we see what it looks like now? Parul, aged 13, Sri Ganganagar, India

What is the meaning of “now” and how does our “now” relate to the “now” somewhere else?

Nothing can travel faster than the speed of light: 300,000 kilometres per second. This means that it takes time for the light from a distant object in the universe to reach us.

Astronomers…

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