Chris Lintott – TRANSCRIPT
So let me tell you what cutting edge astronomy looked like not so long ago. It looked like this.
First of all, that’s just a sketch. Somebody stood at a telescope from night after night, incidentally wearing a top hat, sketching what they could see. And secondly, they’re looking at a single object. In this case, it’s what was known as a spiral nebula. An island universe. A mysterious, massive cluster of stars, that we’d now call a galaxy.
And back then, what we could know about the universe was limited by the amount of data that we could collect, and things just aren’t the same anymore. Modern astrophysics looks not like this, but like this. A picture of a million galaxies from the Sloan Digital Sky Survey. Each dot, an individual system of hundreds of billions of suns.
And if we want to understand the evolution of the universe, if we want to understand how we got this wonderful universe that we see around us, we need to study these galaxies. But there’s a problem. The problem is that we don’t really like the universe that we’ve ended up with. We’ve got this 96% of the universe in a form that we don’t understand. In dark matter and dark energy.
And so we need to pay closer attention to each one of these millions and billions of galaxies. We need to treat them not as points of light, but as individual spirals or galaxies, because the shapes of the galaxies tell us about their history. So you can tell that this spiral galaxy has had a very different past from a big ball of stars that we call the elliptical. That’s what we set out to do. We set out to try and identify the shapes of the galaxies.
And that’s a task that humans are much better at than computers. We’re very good at this sort of pattern recognition task, and computers are really rather poor. We tried getting a student to look at a million galaxies, and I can tell you that, after about the first 50,000, they give up. And so we needed a new solution. We decided to call for help.