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It’s Cold in the Ocean but It’s Hotter Inside Sea Otters – The New York Times

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To stay warm in frigid seas, the marine mammals rely on an unexpected use of the powerhouses of their cells.

Sea otters run hot. It’s not just a manner of speaking: Scientists have found that the furry mammals’ metabolisms work at a rate three times what might normally be expected from a creature their size, burning swiftly through calories.

They seem to be using much of that energy to generate heat, keeping themselves at a toasty 98.6 degrees Fahrenheit in the frigid ocean, where staying warm is a matter of life and death. But the details of their conversion of food and oxygen into vast reserves of heat have been obscure. Now researchers studying sea otters’ muscles report that the feat involves using the mitochondria in their muscle cells in an unexpected way. Their study was published Thursday in the journal Science.

Unlike whales and polar bears, sea otters don’t have a thick insulating layer of blubber, and their celebrated fur — the thickest in the world, with up to 2.6 million hairs per square inch — is not enough on its own to keep them alive in an ocean that can hover on the edge of freezing. Muscles generate heat as they contract, but scientists have known for some time there is another way that muscles can help animals keep warm, a cellular process with the delightful name of proton leak.

Inside almost all animal cells, little pill-shaped organelles called mitochondria break down sugar molecules to extract energy. (Mitochondria are often called the powerhouses of the cell.) During the final stage of this process, protons pop through a membrane. In biology textbooks, the protons helpfully trickle through tiny spinning pores, driving them like water wheels to make adenosine triphosphate, a compound that serves as the molecular battery powering cellular processes.

But reality is not always so tidy. If protons build up faster than the little water wheels can clear them, they seep across the membrane in other ways. And in skeletal muscle cells, this leakage of protons produces substantial amounts of heat. This is thought to contribute to keeping polar animals warm, said Traver Wright, a professor at Texas A&M University and an author of the new paper.

To see how much proton leak might be occurring in sea otters, Dr. Wright and his colleagues put samples of muscle cells from 21 animals into a special chamber that allowed the researchers to monitor the ins and outs of the cells’ mitochondria. They found that sea otters are capable of tremendous quantities of proton leak, suggesting substantial heat-generating capacity. And they were surprised to discover that this ability was present in both tiny otters and full-grown adults.

In general, an organism’s metabolic capacity is linked to its activity level, Dr. Wright said. But young otters, of an age when they would often be resting on their mother; adults of all sizes; and even a relatively inactive captive otter all had similarly high metabolisms and a great capacity for proton leak. In fact, they had higher rates than even Iditarod sled dogs.

“Their leak metabolic rate isn’t anywhere near as high as in sea otters,” said Dr. Wright of the dogs. For otters, he added, “that heat generation is really the driving force of their metabolic development.”

Sea otters are churning through calories even without a lot of physical activity because that energy goes straight into heat, the results suggest. Otters are among the only animals so far for whom proton leak can explain almost all of their elevated metabolism, Dr. Wright said.

The researchers are hoping to study the metabolisms of a variety of animals. They have already published related work on elephant seals, enormous creatures whose lives include both frenetic diving and eating while at sea, as well as weeks of extended lounging on the beach.

Curiously, while the seals loll on the sand for a month, their metabolic capacity does not decrease. Humans taking a similar hiatus from movement with a piña colada and beach reading in hand would not be so lucky.

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Warming Planet Means 83 Million Face Death From Heat This Century – Financial Post

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(Bloomberg) — A population equivalent to that of Germany — 83 million people — could be killed this century because of rising temperatures caused by greenhouse-gas emissions, according to a new study that might influence how markets price carbon pollution.

The research from Columbia University’s Earth Institute introduces a new metric to help companies and governments assess damages wrought by climate change. Accounting for the “mortality cost of carbon” could give polluters new reasons to clean up by dramatically raising the cost of emissions.

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“Based on the decisions made by individuals, businesses or governments, this tells you how many lives will be lost or saved,” said Columbia’s Daniel Bressler, whose research was published Thursday in the journal Nature Communications. “It quantifies the mortality impact of those decisions” by reducing questions down “to a more personal, understandable level.”

Read more: How Biden Is Putting a Number on Carbon’s True Cost: QuickTake 

Adapting models developed by Yale climate economist and Nobel Prize winner William Nordhaus, Bressler calculated the number of direct heat deaths that will be caused by current global-warming trajectories. His calculations don’t include the number of people who might die from rising seas, superstorms, crop failures or changing disease patterns affected by atmospheric warming. That means that the estimated deaths — which approximates the number of people killed in World War 2 — could still be a “vast underestimate,” Bressler said.

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Every 4,434 tons of carbon spewed in 2020 into the Earth’s atmosphere will kill one person this century, according to the peer-reviewed calculations that see the planet warming 4.1 degrees Celsius by 2100. So far the planet has warmed about 1.1 degrees Celsius, compared to pre-industrial times. 

The volume of pollution emitted over the lifetime of three average U.S. residents is estimated to contribute to the death of another person. Bressler said the highest mortality rates can be expected in Earth’s hottest and poorest regions in Africa, the Middle East and South Asia.

Read more: Life and Death in Our Hot Future Will be Shaped by Today’s Income Inequality

The new metric could significantly affect how economies calculate the so-called social cost of carbon, which U.S. President Joe Biden’s administration set at $51 a ton in February. That price on pollution, which complements carbon markets like the European Union’s Emissions Trading System, helps governments set policy by accounting for future damages. But the scale revealed by Bressler’s research suggests the social cost of carbon should be significantly higher, at about $258 a ton, if the world’s economies want to reduce deaths caused by global warming.

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A higher cost on carbon pollution could immediately induce larger emission cuts, which in turn could save lives. Capping global average temperature increase to 2.4 degrees Celsius by the end of the century, compared with modest emissions reductions that would warm the planet 3.4 degrees Celsius, could save 74 million people from dying of heat.

“People shouldn’t take their per-person mortality emissions too personally,” said Bressler. Governments need to mobilize “large-scale policies such as carbon pricing, cap and trade and investments in low carbon technologies and energy storage.”

©2021 Bloomberg L.P.

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Elon Musk's SpaceX saved NASA $500 million – Quartz

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The rocket billionaire discourse, heady as it is, can distract from the facts. Here’s one: NASA saved at least $548 million, and perhaps more, thanks to just one contract with Elon Musk’s SpaceX.

Last week, the US space agency tapped the company’s Falcon Heavy rocket to launch a space probe to one of Jupiter’s moons, Europa, in 2024. The much-awaited Europa Clipper mission will fly by and assess the evidence of water—and extra-terrestrial life—on the astronomical body. The mission was driven through Congress thanks in large part to the support of one former representative, John Culberson, a Texas Republican who navigated it through the sea of veto points and competing priorities that often stands between scientific hopes and their realization.

One way the mission avoided political pitfalls was a linkage with Boeing’s Space Launch System (SLS) rocket, a huge space vehicle designed to return humans to the moon or Mars. The rocket had just one problem: It was hastily assembled from the remains of a canceled NASA program, and there were no concrete plans for it. A decade ago, the folks behind each project joined forces to justify one another’s work. “Once built, SLS would be a rocket with nowhere to fly,” David W. Brown writes in The Mission, his account of the project. “Europa was a somewhere.”

The delayed SLS has yet to fly. Its first mission is expected around the end of this year. But since the SLS became central to the Trump administration’s Artemis program to return to the moon, NASA auditors have pointed out, in addition to the massive cost, that there would not be enough SLS rockets for both the moon and Europa missions.

In 2019, NASA’s inspector general sounded out the possibilities (pdf), and wasn’t bullish on any of them, particularly on price: Even accounting for the fact that the SLS could get the probe to Jupiter faster (saving money spent on the program back home), the system would cost about $726 million. Two other rockets available for purchase, the United Launch Alliance’s Delta IV and the Falcon Heavy, were forecast to cost $450 million each.

The Europa Clipper wound up with a cheaper ride

The deal NASA eventually made with SpaceX for the Falcon Heavy, however, will cost just $178 million. The drop in cost is directly traceable to SpaceX’s approach to designing reusable rockets, and to the partnership NASA struck with Musk’s space firm in its early days.

Think about that: In just two years, the price of launching a space probe fell by 75%; it’s less than the cost of the rocket that launched the latest Mars rover last year. This will enable NASA to direct more resources to other science programs (as well as getting the SLS off the ground).

“Having that launch capability at that price point just saves so much, particularly for the science part of NASA that just does not have the mega-budgets that human spaceflight does,” says Casey Dreier, a space policy analyst at the Planetary Society. “To see other future missions by NASA able to leverage the lift capability of the Heavy at that price point opens up a significant amount of space access.”

The Falcon Heavy, which didn’t even exist when the Europa mission was being planned, has only flown three times. But it will launch at least five more times, including for a NASA mission to an asteroid called Psyche, before the Europa mission is expected to get underway in late 2024.

This is a transformative period for the maturing space industry, as billionaire funders and new business models increase the capacity of private actors. The egos involved may take up a lot of oxygen, but the goals of the commercial space business are not mutually exclusive with NASA’s scientific pursuits; quite the opposite, in fact: They’re enabling more science than before.

A version of this story originally appeared in Quartz’s Space Business newsletter.

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International Space Station Gets Unplanned Shove as Russian Module Arrives – BNN

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(Bloomberg) — The International Space Station got an unplanned push when the thrusters on a new Russian module turned on unexpectedly after docking.

The movements caused a brief loss of attitude control but the space station suffered no damage and none of the seven crew members was injured, ISS flight controllers in Houston said on NASA TV. The U.S National Aeronautics and Space Administration is planning a news conference later Thursday to discuss the incident. 

The mishap occurred a day before Boeing Co. was scheduled to launch its Starliner capsule on a test flight to the orbiting lab as part of NASA’s Commercial Crew Program. The Boeing mission is a do-over of a botched test from December 2019 and the Starliner won’t be carrying a crew on the flight, which is scheduled to blast off from Florida at 2:53 p.m. Eastern time on Friday.

NASA is “monitoring the impact to tomorrow’s launch of the Boeing Starliner spacecraft,” according to a statement by the space agency.

Russian cosmonauts had opened the new Nauka module’s hatch and were incorporating its computers with the existing Zvedza service module when the newly arrived spacecraft began firing at 12:45 p.m. Eastern. The thruster firings changed the station’s attitude by 45 degrees, NASA said. 

A Russian Progress cargo craft attached to the station began firing its own thrusters to counteract the effect from the Nauka module. Roscosmos flight controllers planned to reconfigure the Nauka thrusters to prevent a recurrence, NASA said. The U.S. space agency and Russia are investigating why the unplanned thrusting occurred. 

(Updates with NASA comment in fourth paragraph. A previous version of this story corrected the time in the fifth paragraph.)

©2021 Bloomberg L.P.

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