DW, Quaoar, 2002 AW197, why are all these new, big objects being discovered NOW?
Technology is the reason. Clyde Tombaugh discovered Pluto in 1930 using photographic plates, which let you look at a very wide piece of the sky, but they are not nearly as sensitive as the CCD’s that we use now. (A CCD is what you will find inside most digital cameras.) The new, large objects listed above tend to be just faint enough that they would be out of range of all the older surveys for moving objects done after Tombaugh’s. Today, CCD’s are getting large enough and computers are getting fast enough that it is significantly easier to find these types of planetoids than it was even 5 years ago. We use a 172 Megapixel camera mounted on a robotic telescope to find these things. Even about 5 years ago, such cameras were not available, and the computing power to analyze these cameras was not quite there either.
