The Romans knew our Galaxy as the Via Lactea or “road of milk”. From its gauzy white haze in the sky, it does certainly seem like a fresh, bright line of milk spilled across the speckled dark. Greek myths told the story of Hera pushing away an infant Heracles while she was breastfeeding, spilling drops of her milk that became the array of galaxies we see today. This image of our galaxy (indeed even the word “gala” in Greek means milk) has persisted since the existence of mankind. Whether it be the luminous stripe across the sky or whether it be the flat spiral we visualize looming in deep space, there is a certain image of our home galaxy that we have known for hundreds of thousands of years. And yet, in the universe, nothing is forever.On moonless nights the Andromeda galaxy is bright enough to see with the naked eye, a sister galaxy to the Milky Way with a familiar spiral structure and over a trillion stars — twice that of our own galaxy. It was thought to be a nebula...
learn more
