Neptune is *really* far away

Mike Brown is an astronomer, specifically one who studies Kuiper Belt Objects, those giant frozen iceballs that haunt the solar system out past Neptune. In fact, Neptune's biggest moon Triton has a lot of characteristics similar KBOs -- it may be one captured by Neptune -- so observing it gives an interesting opportunity for a compare-and-contrast study. So this past weekend Mike was using the Keck telescope in Hawaii to observe Triton along with its (adoptive?) parent planet, and took this fantastic image of the pair: