Are we there yet? NASA's New Horizons closes in on Triton and Pluto

As NASA's New Horizons mission heads to Pluto, scientists could get an idea of what to expect by studying Triton, Neptune’s strange icy moon.

New Horizons marked a major anniversary on Aug 25 when the Pluto-bound spacecraft crossed the orbit of Neptune: It was 25 years ago that the Voyager 2 spacecraft first flew by Neptune and its satellite Triton.