Pluto: Three possible models of Dwarf Planet ahead of New Horizons visit

Interior structure models assumed for Pluto.

Two space researchers, Amy Barr, with Brown University and Geoffrey Collins with Wheaton College, have published a paper in the journal Icarus in which they describe three possible interior models of the former planet Pluto.

They suggest the possibilities include: 

1. an undifferentiated rock/ice mixture, 
2. a differentiated rock/ice mixture, and an ocean covered with ice. 
3. The third possibility suggests the likelihood, they claim, of tectonic action on the dwarf planet.

Pluto

A close up view of the planet by space probe New Horizons due to arrive next year, should help clarify which scenario is most likely.

Amy Barr

Scientists believe that Pluto came to exist as it does today, in part due to a collision billions of years ago that led also to the formation of its moon Charon.

Charon

When celestial bodies collide, not only do they knock each other around, they produce heat—heat, the researchers suggest that could still be evident today.

Barr and Collins are leading towards a theory that suggests that shortly after impact, Pluto and Charon were much closer together, the gravity attraction between them would have caused both to be egg shaped.

As time passed, melted ice from the impact would have created an icy crust on top of an ocean on Pluto, and then, as Charon moved farther away, the attractive pull would have diminished, causing ice plates to form and crack against one another, a form of tectonics.

Geoffrey Collins

If that were the case, the two add, then in all likelihood, when New Horizons begins sending back images, they should see evidence of such tectonic action—plate edges thrust into the air, for example.

There's just one catch, Pluto circles the sun in an elliptical orbit, thus sometimes it's much closer to the sun than other times.

When near, it has a defined atmosphere, when far away however, its atmosphere actually freezes to its surface, something that could hide ridges in the ice and thus evidence of both tectonic activity and an ocean beneath the crust of ice.

New Horizons

Artist concept of New Horizons spacecraft.

Johns Hopkins University Applied Physics Laboratory (JHUAPL) /Southwest Research Institute (SwRI)

Since New Horizons will arrive during a time when its atmosphere is frozen to the surface, it might be difficult to determine which of the three proposed models actually describes the relationship between its exterior and interior.

Barr and Collins are optimistic that even in such a scenario, ridges should be apparent, proving that beneath Pluto's icy surface, lies an ocean, one that future researchers might one day sample.

More information: Tectonic Activity on Pluto After the Charon-Forming Impact, Icarus, Available online 4 April 2014. dx.doi.org/10.1016/j.icarus.2014.03.042 . Available on Arxiv: xxx.lanl.gov/abs/1403.6377

DARPA Robotics Challenge: Japan's SCHAFT team ahead on points

For those wondering who of 16 competing teams would walk away as top performers in the two-day DARPA Robotics Challenge in Florida over the weekend, the suspense is over.

SCHAFT, a Japanese military robotics company newly acquired by Google, won the most points, 27 out of a possible 32. SCHAFT outscored some formidable big-name contenders such as MIT, Carnegie Mellon, and NASA. IHMC Robotics placed second.

Third place went to Tartan Rescue, from Carnegie Mellon University, and fourth place was awarded to a team from the Massachusetts Institute of Technology.

The fifth-place went to RoboSimian, designed by NASA's Jet Propulsion Laboratory.

All in all, there were eight top scorers. Team TRACLabs, WRECS (Worcester Polytechnic Institute) and Team TROOPER (Lockheed Martin) were the next three.

The eight teams now have the opportunity to continue their work with the help of Defense Advanced Research Projects Agency (DARPA) funding and are to compete in the finals event where one team will net the $2 million prize at the end of 2014.

The Finals will require robots to attempt a circuit of consecutive physical tasks with degraded communications between the robots and their operators.

DARPA said that the 16 teams at this year's challenge in Miami represented a mix of government, academic and commercial backgrounds. They were not only from the United States, but also from South Korea and Japan.

SCHAFT's high scores were impressive as the DARPA Robotics Challenge (DRC), established to advance state of the art in humanoid robot competition, is considered as a baseline on the current state of robotics.

The event is a marker for assessing the evolution of robots in hazardous first-responder environments, a demonstration of what is so far possible in pushing technologies closer to the point where robots will help out in a range of rescue tasks quickly, efficiently and with minimal human interaction.