"Sand dunes were surprising enough on Titan, but et tu, Pluto? and young, recent dunes? Scientists couldn’t believe their eyes.
Let’s start with Nature‘s brief announcement: “Hundreds of methane dunes nestle at the base of Pluto’s mountains: The formations offer a surprise on a body with such a thin atmosphere.”
Dramatic dunes of methane sweep across part of Pluto. The discovery shows that the dwarf planet’s atmosphere, although thin, can still generate winds powerful enough to blow particles across the surface….
Until now, some researchers thought that Pluto’s atmosphere, which is at 1/100,000th the pressure of Earth’s, could not support winds strong enough to sculpt dunes. But the team’s analysis shows otherwise.
The dunes probably formed in the past 500,000 years — which means Pluto is a geologically active world.
“A geologically active world”— we remember the surprise at the images that suggested ice volcanoes, glaciers, and now sand dunes. Doing the math, we see that 500,000 years (just their theory-laden estimate, not a fact of observation) represents just a 10th of one percent of the assumed age of the solar system. What could have happened so recently to form sand dunes in the fraction of an epoch when human beings can observe them?
Scientists estimate they are up to a kilometer apart. In such a thin atmosphere, the winds must be strong enough to loft the particles and carry them quite a distance over Sputnik Planitia, the heart-shaped flat region that was so surprising to planetary scientists during the 2015 encounter. Alexander Hayes says in his review in Science that the surface pressure on Pluto is 100,000 times weaker than on earth. Even so, winds are not strong enough to lift particles.....
No clue yet why these young dunes have formed only recently..... And yet if these winds have been blowing for 4.6 billion years, shouldn’t the supply have been used up and the process stopped?
Although reporters mention the dunes as having formed only 500,000 years ago, “and possibly much more recently,” none of the news articles or papers so far have addressed the age conundrum for the planet itself.
Monica Grady doesn’t talk about it on The Conversation.
Mike Wall ignores the question on Space.com.
Nadia Drake fails to deal with it at National Geographic.
NASA skips over it at Astrobiology Magazine.
Alan Williams doesn’t address it in a press release from the University of Plymouth.
.... nor does lead author Matt Telfer discuss it in a video clip in that article, even though he adds that scientists believe Pluto’s atmosphere is escaping. Convection and atmospheric escape wouldn’t be issues if Pluto is far younger than scientists believe.
A week before the dunes announcement, a paper appeared in Icarus arguing that “Primordial N2 provides a cosmochemical explanation for the existence of Sputnik Planitia, Pluto.”
The authors state that the inventory of molecular nitrogen (N2) is crucial to understanding the many diverse features on Pluto’s surface. If so, where did it come from? Glein and Waite of Southwest Research Institute (SwRI) say in the paper that the nitrogen accreted during Pluto’s formation from primordial nitrogen or from comets, and it has not been significantly lost to space since then.
But to get their model to work, they have to solve two problems:
(1) how did the ratio of nitrogen to water ice become established, and
(2) what happened to the carbon monoxide?
They offer two suggestions for the latter question: “burial of CO in surface ices, or its destruction from exposure to liquid water.”
The SwRI press release explains this new “cosmochemical model” for Pluto in lay terms. It contains a surprise starting with a b that strains imagination:
Through faith we understand that the worlds were framed by the word of God,...
Hebrews 11:3
Let’s start with Nature‘s brief announcement: “Hundreds of methane dunes nestle at the base of Pluto’s mountains: The formations offer a surprise on a body with such a thin atmosphere.”
Dramatic dunes of methane sweep across part of Pluto. The discovery shows that the dwarf planet’s atmosphere, although thin, can still generate winds powerful enough to blow particles across the surface….
Until now, some researchers thought that Pluto’s atmosphere, which is at 1/100,000th the pressure of Earth’s, could not support winds strong enough to sculpt dunes. But the team’s analysis shows otherwise.
The dunes probably formed in the past 500,000 years — which means Pluto is a geologically active world.
“A geologically active world”— we remember the surprise at the images that suggested ice volcanoes, glaciers, and now sand dunes. Doing the math, we see that 500,000 years (just their theory-laden estimate, not a fact of observation) represents just a 10th of one percent of the assumed age of the solar system. What could have happened so recently to form sand dunes in the fraction of an epoch when human beings can observe them?
Scientists estimate they are up to a kilometer apart. In such a thin atmosphere, the winds must be strong enough to loft the particles and carry them quite a distance over Sputnik Planitia, the heart-shaped flat region that was so surprising to planetary scientists during the 2015 encounter. Alexander Hayes says in his review in Science that the surface pressure on Pluto is 100,000 times weaker than on earth. Even so, winds are not strong enough to lift particles.....
No clue yet why these young dunes have formed only recently..... And yet if these winds have been blowing for 4.6 billion years, shouldn’t the supply have been used up and the process stopped?
Although reporters mention the dunes as having formed only 500,000 years ago, “and possibly much more recently,” none of the news articles or papers so far have addressed the age conundrum for the planet itself.
Monica Grady doesn’t talk about it on The Conversation.
Mike Wall ignores the question on Space.com.
Nadia Drake fails to deal with it at National Geographic.
NASA skips over it at Astrobiology Magazine.
Alan Williams doesn’t address it in a press release from the University of Plymouth.
.... nor does lead author Matt Telfer discuss it in a video clip in that article, even though he adds that scientists believe Pluto’s atmosphere is escaping. Convection and atmospheric escape wouldn’t be issues if Pluto is far younger than scientists believe.
The authors state that the inventory of molecular nitrogen (N2) is crucial to understanding the many diverse features on Pluto’s surface. If so, where did it come from? Glein and Waite of Southwest Research Institute (SwRI) say in the paper that the nitrogen accreted during Pluto’s formation from primordial nitrogen or from comets, and it has not been significantly lost to space since then.
But to get their model to work, they have to solve two problems:
(1) how did the ratio of nitrogen to water ice become established, and
(2) what happened to the carbon monoxide?
They offer two suggestions for the latter question: “burial of CO in surface ices, or its destruction from exposure to liquid water.”
The SwRI press release explains this new “cosmochemical model” for Pluto in lay terms. It contains a surprise starting with a b that strains imagination:
At the heart of the research is the nitrogen-rich ice in Sputnik Planitia, a large glacier that forms the left lobe of the bright Tombaugh Regio feature on Pluto’s surface. “We found an intriguing consistency between the estimated amount of nitrogen inside the glacier and the amount that would be expected if Pluto was formed by the agglomeration of roughly a billion comets or other Kuiper Belt objects similar in chemical composition to 67P, the comet explored by Rosetta.”If you’re not ready to swallow the billion-comets idea, they offer an alternative: “In addition to the comet model, scientists also investigated a solar model, with Pluto forming from very cold ices that would have had a chemical composition that more closely matches that of the Sun.” Are they just covering the bases? Is either model plausible?" CEH
Through faith we understand that the worlds were framed by the word of God,...
Hebrews 11:3