NASA Scientists “Shocked” By New Pluto Discoveries –“Was an Ancient World of Liquid Lakes & Rivers”




At a news conference at the Lunar and Planetary Science Conference on Monday, NASA scientists made it clear that Pluto has many secrets that await discovery. It’s been more than eight months since the historic New Horizons flyby gave us a first time, up close look at that distant dwarf planet. Here are some of the scientific findings that were revealed at the historic session.

“As planetary scientists, what the data revealed did not surprise us. It shocked us,” NASA’s Planetary Science Division Director Jim Green said during the Monday briefing. “What a beautiful system to study.”

“We see what for all the world looks to a lot of our team like a former lake,” Alan Stern, who leads the New Horizons team, said during the news conference. Stern and the rest of the team suspect that Pluto’s mountainous terrain — formed by water ice that freezes as hard as bedrock on the frigid world — has been carved by liquid nitrogen flows.

Describing how New Horizons measured the radar reflectivity of Pluto and shattered the record for most-distant object ever explored by radar, Cathy Olkin, deputy project scientist from Southwest Research Institute, said: “It’s a record that should stand for decades or longer – unless, of course, we use that technique again when New Horizons encounters another Kuiper Belt object."

Richard Binzel, co-investigator from Massachusetts Institute of Technology, Cambridge, Massachusetts, reported on a new understanding of Pluto’s long-term climate variations that include the finding that Pluto has both “tropics” and arctic regions. “Right now, Pluto is between two extreme climate states,” Binzel says. “We are just beginning to understand the long-term climate of Pluto.”

Principal Investigator Stern described evidence that Pluto’s long-term polar axis shifts drive sharp changes in the planet’s atmospheric pressure over time, possibly causing Pluto’s atmosphere to be much more massive than that of even Mars. “In fact,” Stern says, “this opens up the possibility that liquid nitrogen may have once or even many times flowed on Pluto’s surface.”

Discussing the discovery and extensive variety of glacial landforms, glacial flow, and glacial erosion across Pluto. “There are two likely scenarios for the erosion we see,” Orkan Umurhan, postdoctoral researcher from NASA Ames Research Center says “It could be gradual, when much of Pluto’s nitrogen ice was lost over time. Or, it could be part of a cycle in which the nitrogen ice evaporates and redeposits on the highlands, before flowing back into the plains. In all likelihood, both scenarios have been and still are operating.”

Kelsi Singer, postdoctoral researcher from SwRI, reporting on the first age-dating of Pluto’s satellite system from crater counts, showing for the first time that the giant impact believed to have created all of Pluto’s known satellites cannot be recent and instead occurred some 4 billion years ago. “This is our first proof that the giant impact that created the Pluto system must have been ancient, not recent,” Singer says. “That puts the impact on a timeline going back billions of years, rather than millions.”

The Daily Galaxy via

"The Galaxy" in Your Inbox, Free, Daily