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Secrets of deep sea dwelling ultra-black fish unravelled – CANOE

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WASHINGTON — For fish inhabiting the immense darkness of the deep sea, being ultra-black offers great camouflage in a fish-eat-fish world. Scientists studying some of these exotic creatures now have unraveled the secret behind their extreme colour.

These fish – like the fangtooth, the Pacific blackdragon, the anglerfish and the black swallower – have modified the shape, size and packing of the pigment in their skin to the point that it reflects less than 0.5% of light that hits it, researchers said on Thursday.

They studied 16 species that fit this definition of ultra-black. These spanned six different orders of fish – large groupings that each have a shared evolutionary history – indicating this modification evolved independently in all of them.


The ultra-black common fangtooth (Anoplogaster cornuta).

Karen Osborn/Smithsonian /

Handout via REUTERS

“In the deep, open ocean, there is nowhere to hide and a lot of hungry predators,” said zoologist Karen Osborn of the Smithsonian Institution’s National Museum of Natural History in Washington, a co-author of the research published in the journal Current Biology. “An animal’s only option is to blend in with the background.”


The ultra-black Pacific blackdragon (Idiacanthus antrostomus).

Karen Osborn/Smithsonian /

Handout via REUTERS

Very little sunlight penetrates more than 650 feet (200 metres) below the ocean’s surface. Some of these fish reside three miles (5,000 metres) deep.

At such depths, bioluminescence – light emission by living organisms – is the only light source. Some of the ultra-black fish have bioluminescent lures on their bodies to coax prey close enough to be eaten.

The skin of these fish is among the blackest material known, absorbing light so efficiently that even in bright light they appear to be silhouettes, as Osborn discovered when trying to photograph them after they were brought to the surface.

The pigment melanin is abundant in this skin and distributed in an unusual fashion. By packaging perfectly sized and shaped melanosomes – pigment-filled structures within the skin cells – into tightly packed and continuous layers at the skin’s surface, the fish ensure that essentially all light reaching them will hit this layer and never escape.

“This mechanism of making thin and flexible ultra-black material,” Osborn said, “could be used to create ultra-black materials for high-tech optics or for camouflage material for night ops.”

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Watch Japan's Hayabusa2 mission deliver first subsurface asteroid samples to Earth – CBS News

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A Japanese capsule is returning to Earth on Saturday carrying the first-ever rock samples from beneath the surface of an asteroid. When it plummets to Earth, the capsule will provide a stunning show above the Australian outback, streaking across the sky as a dazzling fireball. 

Project manager Yuichi Tsuda called the mission a “rare event in human history.” It marks just the second time pristine, untouched material directly from an asteroid has been brought back to Earth. 

JAXA, Japan’s national aerospace and space agency, was expected to stream the event live at 12:00 p.m. ET on Twitter and YouTubeWatch it here: 


Mission Control Live:Hayabusa2 Capsule Reentry Operation by
jaxasgm on
YouTube

Japan’s Hayabusa2 probe, which is roughly the size of a refrigerator, launched in December 2014, thrilling scientists when it landed on the diamond-shaped asteroid Ryugu, which means “dragon palace” in Japanese, located 185 million miles away. 

On Saturday, it successfully released a capsule for Earth, according to the country’s space agency.

The 15-inch capsule separated from the probe about 136,701 miles above Earth ahead of its planned descent into the Australian outback, near Woomera, South Australia. A parachute will open about six miles above the ground and signals will alert space agency officials to its location.  

This computer graphics image released by JAXA shows the Hayabusa2 spacecraft above the asteroid Ryugu. 

ISAS/JAXA via AP, File


Scientists expect the capsule to bring home a small amount of asteroid material, collected last year, with the goal of learning more about the origins of the solar system and life on Earth. Scientists believe that the rocks that compose the asteroid are around four billion years old.  

The samples could shed light on “how matter is scattered around the solar system, why it exists on the asteroid and how it is related to Earth,” Tsuda told reporters, according to a Friday news release.  

The samples were collected during two separate landings on Ryugu last year. During the first, the probe collected dust and blasted a hole in the asteroid’s surface to find additional material beneath it. Several months later, the probe returned to the crater it created to collect more samples. 

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This Nov. 13, 2019, file image released by JAXA, shows asteroid Ryugu taken by Japan’s Hayabusa2 spacecraft.

JAXA via AP


“We may be able to get substances that will give us clues to the birth of a planet and the origin of life… I’m very interested to see the substances,” mission manager Makoto Yoshikawa told reporters.

But the rescue mission could prove to be a challenge. 

According to The Associated Press, JAXA officials set up satellite dishes, marine radar, drones and helicopters to assist in the scavenger hunt. 

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In this photo provided by JAXA, its crew members set up an antenna in preparation for the capsule collection in Woomera, South Australia in November 2020. 

JAXA via AP


After officials find and collect the capsule, the samples will be processed and flown to Japan, then divided between researchers at JAXA, NASA and other international organizations. 

Some samples will be set aside for future studies when technology has further advanced. 

JAXA plans to extend Hayabusa2’s mission for more than a decade, with its sights set on two new asteroids, 2001 CC21 and 1998 KY26. 

The NASA OSIRIS-REx mission recently collected a sample from another near-Earth asteroid — Bennu, which is similar to Ryugu. The sample will return to Earth in 2023. 

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Japan awaits capsule's return with asteroid soil samples – World News – Castanet.net

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Japan’s Hayabusa2 spacecraft successfully released a small capsule on Saturday and sent it toward Earth to deliver samples from a distant asteroid that could provide clues to the origin of the solar system and life on our planet, the country’s space agency said.

The capsule successfully detached from 220,000 kilometres (136,700 miles) away in a challenging operation that required precision control, the Japan Aerospace Exploration Agency said. The capsule — just 40 centimetres (15 inches) in diameter — is now descending and is expected to land Sunday in a remote, sparsely populated area of Woomera, Australia.

“The capsule has been separated. Congratulations,” JAXA project manager Yuichi Tsuda said.

Hayabusa2 left the asteroid Ryugu, about 300 million kilometres (180 million miles) away, a year ago. After it released the capsule, it moved away from Earth to capture images of the capsule descending toward the planet as it set off on a new expedition to another distant asteroid.

About two hours later, JAXA said it had successfully rerouted Hayabusa2 for its new mission, as beaming staff exchanged fist and elbow touches at the agency’s command centre in Sagamihara, near Tokyo.

“We’ve successfully come this far, and when we fulfil our final mission to recover the capsule, it will be perfect,” mission manager Makoto Yoshikawa said from the command centre during a livestreaming event.

People who gathered to watch the capsule’s separation at public viewing events across Japan cheered the success. ”I’m really glad that the capsule has been successfully released. My heart was beating fast when I was watching,” said Ichiro Ryoko, a 60-year-old computer engineer who watched at Tokyo Dome.

Hayabusa2’s return with the world’s first asteroid subsurface samples comes weeks after NASA’s OSIRIS-REx spacecraft made a successful touch-and-go grab of surface samples from asteroid Bennu. China, meanwhile, announced this week that its lunar lander collected underground samples and sealed them within the spacecraft for their return to Earth, as space developing nations compete in their missions.

In the early hours of Sunday, the capsule, protected by a heat shield, will briefly turn into a fireball as it reenters the atmosphere 120 kilometres (75 miles) above Earth. At about 10 kilometres (6 miles) aboveground, a parachute will open to slow its fall and beacon signals will be transmitted to indicate its location.

JAXA staff have set up satellite dishes at several locations in the target area to receive the signals. They also will use a marine radar, drones and helicopters to assist in the search and retrieval of the pan-shaped capsule.

Australian National University space rock expert Trevor Ireland, who is in Woomera for the arrival of the capsule, said he expected the Ryugu samples to be similar to the meteorite that fell in Australia near Murchison in Victoria state more than 50 years ago.

“The Murchison meteorite opened a window on the origin of organics on Earth because these rocks were found to contain simple amino acids as well as abundant water,” Ireland said. “We will examine whether Ryugu is a potential source of organic matter and water on Earth when the solar system was forming, and whether these still remain intact on the asteroid.”

Scientists say they believe the samples, especially ones taken from under the asteroid’s surface, contain valuable data unaffected by space radiation and other environmental factors. They are particularly interested in analyzing organic materials in the samples.

JAXA hopes to find clues to how the materials are distributed in the solar system and are related to life on Earth. Yoshikawa, the mission manager, said 0.1 gram of the dust would be enough to carry out all planned researches.

For Hayabusa2, it’s not the end of the mission it started in 2014. It is now heading to a small asteroid called 1998KY26 on a journey slated to take 10 years one way, for possible research including finding ways to prevent meteorites from hitting Earth.

So far, its mission has been fully successful. It touched down twice on Ryugu despite the asteroid’s extremely rocky surface, and successfully collected data and samples during the 1 1/2 years it spent near Ryugu after arriving there in June 2018.

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Raising a flag on the moon is much harder than you think – CGTN

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Almost all of us have had a flag raising experience. Hold it, then raise it. It’s so easy.

But doing so on the moon can be exceptionally difficult.

As the Chinese moon sampler Chang’e-5 raised the national flag on the moon, let’s check out the effort engineers put into this significant achievement.

How to make it fly?

The moon is so small compared to the Earth that it cannot maintain an atmosphere, which leads to the first problem for flag raising – there’s no wind to keep the flag expanded.

You may have seen images of the U.S. flag apparently flying during the Apollo missions. That’s just an illusion. The fact is, in addition to the vertical pole where the flag is attached to, there’s also a horizontal pole to make it stay horizontal.

The Chinese design of the flag pole is a bit different.

In the previous Chang’e missions, the national flag was painted on the surface of the moon landers and rovers. But in the Chang’e-5 mission, the flag was rolled up before being expanded.

Engineers test the rolling mechanism at the China Academy of Space Technology (CAST) /Wuhan Textile University

Engineers test the rolling mechanism at the China Academy of Space Technology (CAST) /Wuhan Textile University

Also, as a Chinese astronaut has yet to land on the moon, the work has to be done by machines – a robotic arm, to be specific.

According to a report from China National Radio, the whole flag raising system must weigh less than 1 kg in order to keep the whole lander lightweight. Yet the robot arm must be able to endure sudden temperature changes during the launch, the radiation from the sun and the air-less environment on the moon.

The engineers tried many mechanisms to display the flag, including memory metal and unfolding the flag like a traditional Chinese fan. Eventually the rolling-out solution worked best in simulations.

Finding the best cloth

Normal flags on Earth will be bleached or even destroyed on the moon because of the radiation from the sun. Many speculated that this may have happened to some of the six Apollo flags, though there have been no observations to prove that yet.

“Strong fabrics are usually hard to dye, while easy-to-dye fabrics are usually fragile,” said Cheng Chang, who is in charge of the flag-raising system of the Chang’e-5. “It took our team more than a year to find the perfect material.”

The researchers behind the cloth revealed how they made it.

The team works for the Wuhan Textile University, and is led by professor Xu Weilin.

Xu (L2) talks with his team members about the cloth technology. /Wuhan Textile University

Xu (L2) talks with his team members about the cloth technology. /Wuhan Textile University

“The flag was mainly made of high-end aramid fibers with our own technology,” the university wrote on its website. “It can endure extreme ultraviolet radiation.”

The team also used their own nanomaterial to prevent the color from vaporizing.

“It’s a highly customized product for the space mission,” China Space News reported.

While the Chinese-language internet is amazed at how adorable the pop-up flag is, we should also know and remember the teams behind this complicated effort.

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