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.


Study: Smokers better off quitting, even with weight gain

In this June 22, 2012 file photo, a smoker extinguishes a cigarette in an ash tray in Sacramento, Calif. (AP)
Updated 18 August 2018
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Study: Smokers better off quitting, even with weight gain

  • Quitters saw their risk of diabetes increase by 22 percent in the six years after they kicked the habit
  • The people enrolled in the studies were all health professionals, and did not mirror current smokers in the general population, who are disproportionately low-income, less-educated and more likely to smoke heavily

NEW YORK: If you quit smoking and gain weight, it may seem like you’re trading one set of health problems for another. But a new US study finds you’re still better off in the long run.
Compared with smokers, even the quitters who gained the most weight had at least a 50 percent lower risk of dying prematurely from heart disease and other causes, the Harvard-led study found.
The study is impressive in its size and scope and should put to rest any myth that there are prohibitive weight-related health consequences to quitting cigarettes, said Dr. William Dietz, a public health expert at George Washington University.
“The paper makes pretty clear that your health improves, even if you gain weight,” said Dietz, who was not involved in the research. “I don’t think we knew that with the assurance that this paper provides.”
The New England Journal of Medicine published the study Wednesday. The journal also published a Swedish study that found quitting smoking seems to be the best thing diabetics can do to cut their risk of dying prematurely.
The nicotine in cigarettes can suppress appetite and boost metabolism. Many smokers who quit and don’t step up their exercise find they eat more and gain weight — typically less than 10 pounds (4.5 kilograms), but in some cases three times that much.
A lot of weight gain is a cause of the most common form of diabetes, a disease in which blood sugar levels are higher than normal. Diabetes can lead to problems including blindness, nerve damage, heart and kidney disease and poor blood flow to the legs and feet.
In the US study, researchers tracked more than 170,000 men and women over roughly 20 years, looking at what they said in health questionnaires given every two years.
The people enrolled in the studies were all health professionals, and did not mirror current smokers in the general population, who are disproportionately low-income, less-educated and more likely to smoke heavily.
The researchers checked which study participants quit smoking and followed whether they gained weight and developed diabetes, heart disease or other conditions.
Quitters saw their risk of diabetes increase by 22 percent in the six years after they kicked the habit. An editorial in the journal characterized it as “a mild elevation” in the diabetes risk.
Studies previously showed that people who quit have an elevated risk of developing diabetes, said Dr. Qi Sun, one the study’s authors. He is a researcher at the Harvard-affiliated Brigham and Women’s Hospital.
But that risk doesn’t endure, and it never leads to a higher premature death rate than what smokers face, he said.
“Regardless of the amount of weight gain, quitters always have a lower risk of dying” prematurely, Sun said.