Standard image of the new scientist

Why the vast emptiness of the room isn’t really that empty after all

Spacetime may seem empty, but the space between the stars is full of more interesting things than you might think, writes Chanda Prescod-Weinstein

room


| comment

4th November 2020

By Chanda Prescod-Weinstein

World History Archive / Alamy

SPACE-TIME is mostly empty. Although there are at least 100 billion galaxies – each with about 100 billion stars – and a lot of galactic dust, the universe is so large that there are huge space-time segments between each star and even more between each galaxy. Even the closest star to earth (the sun) is almost 150 million kilometers away, which means that the fastest thing in the universe (light) needs 8 minutes to get from there to here despite a speed of 300,000 kilometers per second reach.

It seems like most of it is between earth and sun …