All Space Considered, Jan 2015 Pt. 1 (New Horizons)

Attendees of All Space Considered this past Friday (the first ASC of 2015) were treated to Alan Stern, Principal Investigator of the New Horizons mission.  He teleconferenced in from his home in Colorado and told us all about the mission.

New Horizons is humanity's first trip intended to study objects beyond the outer solar system.  It is going to Pluto and will study both Pluto and its moon, Charon.  The term "outer solar system" is traditional and loosely means the gas giants.  With the discovery of multiple objects in the Kuiper Belt  as well as continued discovery of long-period comets, it has become clear that there are entire populations of objects orbiting the sun beyond Neptune, not just Pluto.  That discovery is what pushed New Horizons into existence.  Despite decades of work by various scientists to get a Pluto mission funded and approved by NASA, it was only after direct observation of other Kuiper Belt objects that New Horizons was, in fact, approved.

Stern's appearance coincides with New Horizons having woken up out of its final sleep on approach to Pluto.  That happened on Dec 6 and everyone is now looking forward to the six months of observations New Horizons will make, beginning in February.  The closest approach to Pluto will be on July 14, but a full 10 weeks before that, the images New Horizons takes will begin to exceed the resolution of our current best images, primarily taken by the Hubble Space Telescope.  Stern mentioned that an image of Earth at the same resolution as our current best Pluto images would not even resolve the continents.  The best pictures from New Horizons, on the other hand, will be able to resolve features on a human scale.  His exact words were, "If we were looking at Earth, we would be able to see the ponds in Central Park."  We will, of course, get similar data on Charon.

The reason New Horizons will only be observing Pluto for six months, unlike Cassini at Saturn or Curiosity at Mars, is that it is a fly-by mission like the Voyagers.  Pluto doesn't have enough gravity to capture the satellite, which has to travel at fairly extreme velocity to get there in a reasonable time.  While it would be really nice to be able to orbit, flying past Pluto introduces the possibility of studying other Kuiper Belt objects.  Two objects have been identified by Hubble, but Stern was very clear that the selection of that target will not happen until August or so, not wanting to distract his team or compromise the collection of data at Pluto.

New Horizons will provide us with our best data of the Universe beyond the outer solar system.  This will provide us with information on how our solar system formed, how systems might form around other stars and, ultimately, how that whole story might lead to habitability on other stars.  And, as always, simply doing the science will lead us to whole new questions we didn't even know to ask before.  I think I speak for everyone in the audience at All Space Considered in expressing gratitude to Alan Stern and the staff at Griffith Observatory for giving us a glimpse into New Horizons, Pluto and our Universe.