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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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Facial Recognition—Now for Seals – Hakai Magazine

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Have you ever looked at a seal and thought, Is that the same seal I saw yesterday? Well, there could soon be an app for that based on new seal facial recognition technology. Known as SealNet, this seal face-finding system was developed by a team of undergraduate students from Colgate University in New York.

Taking inspiration from other technology adapted for recognizing primates and bears, Krista Ingram, a biologist at Colgate University, led the students in developing software that uses deep learning and a convolutional neural network to tell one seal face from another. SealNet is tailored to identify the harbor seal, a species with a penchant for posing on coasts in haulouts.

The team had to train their software to identify seal faces. “I give it a photograph, it finds the face, [and] clips it to a standard size,” says Ingram. But then she and her students would manually identify the nose, the mouth, and the center of the eyes.

For the project, team members snapped more than 2,000 pictures of seals around Casco Bay, Maine, during a two-year period. They tested the software using 406 different seals and found that SealNet could correctly identify the seals’ faces 85 percent of the time. The team has since expanded its database to include around 1,500 seal faces. As the number of seals logged in the database goes up, so too should the accuracy of the identification, Ingram says.

The developers of SealNet trained a neural network to tell harbor seals apart using photos of 406 different seals. Photo courtesy of Birenbaum et al.

As with all tech, however, SealNet is not infallible. The software saw seal faces in other body parts, vegetation, and even rocks. In one case, Ingram and her students did a double take at the uncanny resemblance between a rock and a seal face. “[The rock] did look like a seal face,” Ingram says. “The darker parts were about the same distance as the eyes … so you can understand why the software found a face.” Consequently, she says it’s always best to manually check that seal faces identified by the software belong to a real seal.

Like a weary seal hauling itself onto a beach for an involuntary photo shoot, the question of why this is all necessary raises itself. Ingram believes SealNet could be a useful, noninvasive tool for researchers.

Of the world’s pinnipeds—a group that includes seals, walruses, and sea lions—harbor seals are considered the most widely dispersed. Yet knowledge gaps do exist. Other techniques to track seals, such as tagging and aerial monitoring, have their limitations and can be highly invasive or expensive.

Ingram points to site fidelity as an aspect of seal behavior that SealNet could shed more light on. The team’s trials indicated that some harbor seals return to the same haulout sites year after year. Other seals, however, such as two animals the team nicknamed Clove and Petal, appeared at two different sites together. Increasing scientists’ understanding of how seals move around could strengthen arguments for protecting specific areas, says Anders Galatius, an ecologist at Aarhus University in Denmark who was not involved in the project.

Galatius, who is responsible for monitoring Denmark’s seal populations, says the software “shows a lot of promise.” If the identification rates are improved, it could be paired with another photo identification method that identifies seals by distinctive markings on their pelage, he says.

In the future, after further testing, Ingram hopes to develop an app based on SealNet. The app, she says, could possibly allow citizen scientists to contribute to logging seal faces. The program could also be adapted for other pinnipeds and possibly even for cetaceans.

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NASA launches nanosatellite in preparation for lunar 'Gateway' station – Yahoo News Canada

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The rocket carrying the Capstone satellite lifts off. (NASA)

Nasa has launched a tiny CubeSat this week to test and orbit which will soon be used by Gateway, a lunar space station.

It’s all part of the space agency’s plan to put a woman on the moon by 2025.

The Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (Capstone) mission launched from New Zealand on Tuesday.

Jim Reuter, associate administrator for the Space Technology Mission Directorate, said: “Capstone is an example of how working with commercial partners is key for Nasa’s ambitious plans to explore the moon and beyond.

“We’re thrilled with a successful start to the mission and looking forward to what Capstone will do once it arrives at the Moon.”

Read more: Astronomers find closest black hole to Earth

The satellite is currently in low-Earth orbit, and it will take the spacecraft about four months to reach its targeted lunar orbit.

Capstone is attached to Rocket Lab’s Lunar Photon, an interplanetary third stage that will send it on its way to deep space.

Over the next six days, Photon’s engine will periodically ignite to accelerate it beyond low-Earth orbit, where Photon will release the CubeSat on a trajectory to the moon.

Capstone will then use its own propulsion and the sun’s gravity to navigate the rest of the way to the Moon.

The gravity-driven track will dramatically reduce the amount of fuel the CubeSat needs to get to the Moon.

Read more: There might once have been life on the moon

Bradley Cheetham, principal investigator for CAPSTONE and chief executive officer of Advanced Space, “Our team is now preparing for separation and initial acquisition for the spacecraft in six days.

“We have already learned a tremendous amount getting to this point, and we are passionate about the importance of returning humans to the Moon, this time to stay!”

At the moon, Capstone will enter an elongated orbit called a near rectilinear halo orbit, or NRHO.

Once in the NRHO, Capstone will fly within 1,000 miles of the moon’s north pole on its near pass and 43,500 miles from the south pole at its farthest.

It will repeat the cycle every six-and-a-half days and maintain this orbit for at least six months to study dynamics.

“Capstone is a pathfinder in many ways, and it will demonstrate several technology capabilities during its mission timeframe while navigating a never-before-flown orbit around the Moon,” said Elwood Agasid, project manager for Capstone at Nasa’s Ames Research Center in California’s Silicon Valley.

“Capstone is laying a foundation for Artemis, Gateway, and commercial support for future lunar operations.”

Nasa estimates the cost of the whole Artemis mission at $28bn.

It would be the first time people have walked on the moon since the last Apollo moon mission in 1972.

Just 12 people have walked on the moon – all men.

Nasa flew six manned missions to the surface of the moon, beginning with Neil Armstrong and Buzz Aldrin in July 1969, up to Gene Cernan and Jack Schmitt in December 1972.

The mission will use Nasa’s powerful new rocket, the Space Launch System (SLS), and the Orion spacecraft.

Watch: NASA launch paves way for moon orbit station

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The year’s biggest and brightest supermoon will appear in July & here’s when you’ll … – Curiocity

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Summer is here and with it? Sunshine – and some serious moonshine (of the visible variety, of course). This upcoming month, look up in anticipation of the biggest and brightest event of the year, the July Buck supermoon – which will hover over North America on July 13th.

Appearing 7% larger and lower in the sky, this particular event will be one well worth keeping an eye on when it rises above the horizon.

This will be the closest we’ll get to our celestial neighbour in 2022 (357,418 km) and while North America won’t get to see it when it reaches peak illumination at 2:38 pm ETC., it’ll still look pretty dang impressive after the sunsets.

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Not sure when the moon rises in your area? Here’s the earliest that you’ll be able to see the moon in various cities across the continent according to the Farmer’s Almanac.

  • Seattle, Washington  – 9:50 pm PDT
  • Vancouver, British Columbia – 10:02 pm PDT
  • Calgary, Alberta – 10:35 pm MST
  • Edmonton, Alberta – 10:49 pm MST
  • Toronto, Ontario – 9:34 pm MST
  • Montreal, Quebec – 9:18 pm MST

Until then, cross your fingers for a clear sky, friends! It’s going to be incredible.

Happy viewing.

JULY BUCK SUPERMOON 

When: Wednesday, July 13th

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