July 17, 2015
Maunakea, Hawaii –The past two weeks have been 14 monumental days for beings on Earth interested in Pluto and its five moons.
While many people think it’s pretty cool to see images of features like ice mountains on the most mysterious planet (even if it is a dwarf) in our solar system, imagine the excitement of the scientists that have made a career of studying Pluto having never seen it; or the engineers that built and programmed the craft, the instruments, and the flight path that had New Horizons travel the length of our solar system for nearly a decade.
This animation combines various observations of Pluto over the course of several decades. The first frame is a digital zoom-in on Pluto as it appeared upon its discovery by Clyde Tombaugh in 1930 (image courtesy Lowell Observatory Archives). The other images show various views of Pluto as seen by NASA's Hubble Space Telescope beginning in the 1990s and NASA's New Horizons spacecraft in 2015. The final sequence zooms in to a close-up frame of Pluto released on July 15, 2015.
New Horizons was launched aboard an Atlas V rocket from Florida more than nine years ago at a record-breaking 36,000 miles per hour. The NASA craft then made a brief encounter with an asteroid, and proceeded to Jupiter where its 2007 flyby provided a gravity boost, increasing its speed by more than 9,000 miles per hour. From there it tested its equipment, then hibernated except for annual system checks until January of this year, when it woke up and began its approach to Pluto.
While NASA HQ is buzzing with activity, Hawaii has also seen its share of action, offering significant contributions to the science that is being done to understand our least-known neighbors. The W. M. Keck Observatory and several other observatories on Maunakea have gathered data that the instruments on New Horizons are not capable of collecting.
For the first two weeks of June, NASA scientists have been at Keck Observatory, using its two telescopes to gather data about the chemical composition of its surface and atmosphere and how they interact.
"We are using Keck Observatory to get spectra of Pluto at wave lengths New Horizons can’t get,” said Eliot Young, principal scientist for the NASA observations. “We don’t know everything that the Keck Observatory data will show us, but one thing I know it will show us is how different ices are mixed or separated on Pluto.
Young and his team suspect there are sources of methane on the surface feeding the atmosphere, which might lead to more interesting discoveries. “Wherever we find methane and nitrogen together, we find more complex organic molecules," he said.
Because Pluto has 56 days for every Earth year, it takes almost week for it to complete a single rotation giving us an interesting data set By spreading out those observations over 14 days, there’s enough information to see how the surface changes over a time.
“If you have enough data, you can see where stuff evaporates over many years and interpret the sub structure based on that,” he said. “That might tell you what’s under the surface and we don’t get many chances to see what’s under the surface so that’s a big deal to us.”