Other Galaxies Are Closer Than You Think

Really, if our galaxy were the size of a dime, the Andromeda Galaxy (M31) would be about the size of a quarter and just 20 inches away. Pull out a dime and quarter and lay them on a table on either side of two hands spread apart to see a rough approximation of the sizes.

Here's a negative image of M31 recorded, believe it or not, in 1894. The telescope was a 24-inch reflector located in Ireland. The astronomers used glass plates treated with a photographic silver halide emulsion as the 'film' to record the image.

Almost all those little black dots are stars in our galaxy. There are no stars in space between galaxies. The somewhat larger fuzzy spots are other galaxies even farther away.

Here's another image of M31 recorded with modern electronic equipment sensitive to x-ray light onboard the Spitzer space telescope. It's in orbit, like the Hubble, but it's designed to see light with shorter wavelengths.

There are more stars in M31 than there are grains of sand on all the beaches on earth.

But don't plan on a trip to Andromeda any time soon. In astronomical terms it's relatively close, but in human terms it's a veeeery long way away. Even at the speed of light it would take two and half million years to get there.

In fact, the pictures we take are created with light that left Andromeda 2,500,000 years ago. Who knows what it looks like now!*


* Actually, the answer is it doesn't look very different. In astronomical terms not much changes in a coupla million years.


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