A layered, hazy atmosphere. Blue skies. And clouds? New Horizons scientists are discussing the potential of clouds in Pluto’s skies this week at the American Astronomical Society Division for Planetary Sciences (DPS) and European Planetary Science Congress (EPSC) in Pasadena, California.
Whew, I feel for the person doing the program brochure on that one.
The idea of clouds on Pluto isn’t a new one. We first heard rumblings of possible clouds back in March. Today, several more images were released pointing the features out. And it’s the best look we’re going to get.
The third image on the top row looks like the best example of a cloud. We do not see obvious cloud decks, just lone features that don’t have an immediate explanation. The New Horizon team can’t say with 100% certainty that they are clouds. Stereo imaging just isn’t enough for them to confirm it.
“If there are clouds, it would mean the weather on Pluto is even more complex than we imagined,” says Alan Stern, principal investigator of the New Horizons mission.
The bright material contrasting with the red landscape is believed to be methane that has condensed as ice atop the peaks. “That this material coats only the upper slopes of the peaks suggests methane ice may act like water in Earth’s atmosphere, condensing as frost at high altitude,” said John Stansberry, a member of the New Horizons team.
Clouds would indicate there’s much more condensation going on. If there are clouds, how frequently do they form? We are looking at a snapshot of Pluto. This is how it looked for a few hours in July 2015. We don’t know just how dynamic Pluto’s weather is. And unfortunately, we’ll have to wait for another mission to head to Pluto to find out. Next time, let’s enter orbit.
New Horizons is downlinking the last few megabytes of data. The last of it should be back on Earth on Sunday. But the science work will go on. Years of analysis will tease as many secrets from Pluto as possible.