TED-ED: Light seconds, light years, light centuries: How to measure extreme distances - Yuan-Sen Ting

The video explains how astronomers measure vast distances in space using light years, parallax, and standard candles like cepheid variables and type 1a supernovae. It highlights the importance of observing distant objects to understand the universe's history, as light from these objects acts as a time machine, showing us the past.

Explain the significance of type 1a supernovae as standard candles.

Why is it important to observe distant objects in the universe?

How does the light we see from distant stars and galaxies serve as a time machine?