Professor Gerry Gilmore
gaia project’s lead investigator spills the space beans
So how does Gaia’s billionpixel snapper work?
The individual sensors are, in principle, similar to the ones in a commercial camera. There are 106 in total, each ten-meg, and they can see an object the diameter of a human hair from 1,000km away. That’s the equivalent of being able to tell the difference between the left and right side of a shirt button on the Moon.
Why do we need such a sensitive cam in space?
Gaia will measure the location of one billion stars in three dimensions. By doing this 80 times on average for all of the Milky Way’s billion stars over five or six years, we’ll be able to reconstruct how the galaxy was assembled. We think it was formed from a large number of small galaxies coming together and if we measure the orbits we’ll find out.