Underground ocean found on Pluto, likely slushy with ice

This picture of Pluto was taken from the Long Range Reconnaissance Imager (LORRI) aboard NASA’s New Horizons spacecraft on July 13, 2015 when the spacecraft was 476,000 miles (768,000 kilometers) from the surface. (NASA/Handout via REUTERS)
Updated 16 November 2016
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Underground ocean found on Pluto, likely slushy with ice

HOUSTON, United States: Scientists have found evidence that tiny, distant Pluto harbors a hidden ocean beneath the frozen surface of its heart-shaped central plain containing as much water as all of Earth’s seas.
The finding, reported on Wednesday in two research papers published in the journal Nature, adds Pluto to a growing list of worlds in the solar system beyond Earth believed to have underground oceans, some of which potentially could be habitats for life.
Pluto’s ocean, which is likely slushy with ice, lies 93 to 124 miles (150 to 200 km) beneath the dwarf planet’s icy surface and is about 62 miles (100 km) deep, planetary scientist Francis Nimmo of the University of California, Santa Cruz said in an interview.
With its ocean covered by so much ice, Pluto is not a prime candidate for life, added Massachusetts Institute of Technology planetary scientist Richard Binzel, another of the researchers. But Binzel added that “one is careful to never say the word impossible.”
Liquid water is considered one of the essential ingredients for life.
The discovery was made through an analysis of images and data collected by NASA’s New Horizons spacecraft, which flew past Pluto and its entourage of moons in July 2015.
“It shows that nature is more creative than we are able to imagine, which is why we go and explore,” Binzel said. “We see what nature is capable of doing.”
Despite being about 40 times farther from the sun than Earth, Pluto has enough radioactive heat left over from its formation 4.6 billion years ago to keep water liquid.
“Pluto has enough rock that there’s quite a lot of heat being generated, and an ice shell a few hundred kilometers thick is quite a good insulator,” Nimmo said. “So a deep subsurface ocean is not too surprising, especially if the ocean contains ammonia, which acts like an antifreeze.”
Scientists made the discovery as they were trying to figure out why a 621-mile (1,000-km) wide impact basin known as Sputnik Planitia, which contains the curious heart-shaped region, was located in its present position near Pluto’s equator.
Computer models showed the basin likely filled with ice, which caused Pluto to roll over, cracking its crust. That could happen only if Pluto possessed a subsurface ocean, the analysis found.
New Horizons is on its way to another frozen world in the Kuiper Belt region of the solar system about 1 billion miles (1.6 billion km) past Pluto. A flyby of the object, known as 2014 MU69, is scheduled on Jan. 1, 2019.


Scientists amazed as Canadian permafrost thaws 70 years early

General view of a landscape of partially thawed Arctic permafrost near Mould Bay, Canada, in this handout photo released June 18, 2019. (Reuters)
Updated 19 June 2019
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Scientists amazed as Canadian permafrost thaws 70 years early

  • “This premature thawing is another clear signal that we must decarbonize our economies, and immediately”

LONDON: Permafrost at outposts in the Canadian Arctic is thawing 70 years earlier than predicted, an expedition has discovered, in the latest sign that the global climate crisis is accelerating even faster than scientists had feared.
A team from the University of Alaska Fairbanks said they were astounded by how quickly a succession of unusually hot summers had destabilized the upper layers of giant subterranean ice blocks that had been frozen solid for millennia.
“What we saw was amazing,” Vladimir E. Romanovsky, a professor of geophysics at the university, told Reuters by telephone. “It’s an indication that the climate is now warmer than at any time in the last 5,000 or more years.”
With governments meeting in Bonn this week to try to ratchet up ambitions in United Nations climate negotiations, the team’s findings, published on June 10 in Geophysical Research Letters, offered a further sign of a growing climate emergency.
The paper was based on data Romanovsky and his colleagues had been analizing since their last expedition to the area in 2016. The team used a modified propeller plane to visit exceptionally remote sites, including an abandoned Cold War-era radar base more than 300 km from the nearest human settlement.
Diving through a lucky break in the clouds, Romanovsky and his colleagues said they were confronted with a landscape that was unrecognizable from the pristine Arctic terrain they had encountered during initial visits a decade or so earlier.
The vista had dissolved into an undulating sea of hummocks — waist-high depressions and ponds known as thermokarst. Vegetation, once sparse, had begun to flourish in the shelter provided from the constant wind.
Torn between professional excitement and foreboding, Romanovsky said the scene had reminded him of the aftermath of a bombardment.
“It’s a canary in the coalmine,” said Louise Farquharson, a post-doctoral researcher and co-author of the study. “It’s very likely that this phenomenon is affecting a much more extensive region and that’s what we’re going to look at next.”
Scientists are concerned about the stability of permafrost because of the risk that rapid thawing could release vast quantities of heat-trapping gases, unleashing a feedback loop that would in turn fuel even faster temperature rises.
Even if current commitments to cut emissions under the 2015 Paris Agreement are implemented, the world is still far from averting the risk that these kinds of feedback loops will trigger runaway warming, according to models used by the UN-backed Intergovernmental Panel on Climate Change.
With scientists warning that sharply higher temperatures would devastate the global south and threaten the viability of industrial civilization in the northern hemisphere, campaigners said the new paper reinforced the imperative to cut emissions.
“Thawing permafrost is one of the tipping points for climate breakdown and it’s happening before our very eyes,” said Jennifer Morgan, Executive Director of Greenpeace International. “This premature thawing is another clear signal that we must decarbonize our economies, and immediately.”