---
title: "Home sweet home"
date: "2013-03-08T11:36:03+00:00"
modified: "2013-03-08T11:36:03+00:00"
url: "https://rationalists.org.uk/articles/home-sweet-home/"
post_id: 5724
---

# Home sweet home

![Milky way](https://rationalists.org.uk/wp-content/uploads/sites/2/images/Chown "Milky way")

We live in a great whirlpool of 100 billion stars, turning ponderously in the night. Our Milky Way, which looks edge-on like two fried eggs back-to-back, is just one of 100 billion galaxies receding from each other in the aftermath of the Big Bang. But our modern picture has taken centuries to piece together.

To ancient peoples, the Milky Way seemed like a trail of milk spilled across the heavens, hence its name. Galileo, using his new-fangled telescope in 1610, saw it was made of innumerable stars. But it was not until 1755 that Immanuel Kant guessed that the Milky Way is a giant rotating body of stars – and that we are in it.

The story shifts to a bog in the centre of Ireland. There, in 1845, using the “Leviathan” – the biggest telescope in the world for 72 years – Lord Rosse discovered spiral-shaped “nebulae”. But were they clouds of glowing gas in the Milky Way, or collections of stars blurred together by distance and beyond the Milky Way? Only in 1923 did Edwin Hubble prove they were separate “galaxies” and that the Milky Way was one of them.

But interstellar dust hangs like a curtain across space, obscuring our view of the Milky Way – at least in visible light. However, dust glows with invisible “infrared”. And it is with infrared light that this image was taken by the 2MASS – “2 Micron All-Sky Survey” – in 2005. At last, we can see our galaxy: Home Sweet Home.

**Marcus Chown‘s latest books are Tweeting the Universe and Solar System, both published by Faber**