Q:

How long does it take light to reach Earth?

A:

Light from the Sun travels 93 million miles, at a speed of 186,000 miles per second, to get to Earth in about 8 minutes and 20 seconds. People on Earth see the Sun as it was 8 minutes and 20 seconds ago.

People also see stars and galaxies as they were when the light reaching the Earth was first emitted. The galaxy MACS0647-JD is 13.3 billion light-years away, so the light from it just reaching Earth now was first emitted when the universe was only 400 million years old. The Sun only formed 4.5 billion years ago, so the light from that galaxy is over twice the age of the Sun.

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