A Little Bot of Galactic Possibility

The hugeness of the Andromeda Galaxy, one tweet at a time


The Andromeda Galaxy is so close, sometimes we mistake it for our own.

Andromeda—or Messier 31, as it's known scientifically—is the nearest galaxy to the Milky Way. It’s also, like the Milky Way, a spiral, so textbooks sometimes use it to represent for the Milky Way in explanations. We can’t see our own galaxy from far away, but Andromeda is probably what it looks like.

And now, we have an even better sense of what Andromeda looks like.

Earlier this month, NASA released the largest photo ever of Andromeda. Captured by the Hubble Space Telescope, the composite image comprises more than 1.5 billion pixels. “You would need more than 600 HD television screens to display the whole image,” said the agency in an official release.

It’s so huge, in fact, that it has to be navigated much like Google Maps, with a zoom bar and a window. Or it can be navigated a different way—piece by piece, over time.

A new Twitter account, @AndromedaBot, tweets a small fraction of the huge image every 30 minutes. Every chunk is impressive: The pictures no longer show macro-patterns in the galaxy, but instead reveal star field after star field. Some of these are so dense the whole image looks yellow:

While others are more comparatively sparse:

Every single one of those points of light is a star, not a galaxy. Some of them have planets: gas giants like Jupiter, rocky Marses, or maybe even blue homes like Earth. Every point of light is a possibility.

This is one of my favorite types of Twitter bots. We could call it a Bot of Reminding. Another Bot of Reminding is @EveryThreeMinutes, which tweets every 180 seconds that, in the antebellum American South, a slave was bought and sold every three minutes. It’s a reminder of historical enormity.

Another account, @WWIIinRealTime, isn't a bot, but it also unfolds history over time, helping us to understand the sweep of events as experienced.

Yet another tool in this camp—though one not on Twitter—is Google Chrome’s Earthview extension. With Earthview, every time a user opens a new tab, they’re presented with a satellite image of somewhere on the planet. Like @AndromedaBot, it showcases a different kind of possibility: This is somewhere on the planet you are now.