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B.C.'s "living dinosaurs" threatened by ocean warming and acidification – Straight.com

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The world’s warming oceans and the ongoing acidification of seawater are having a serious effect on B.C.’s rare glass sponges and their associated reefs, according to a study conducted by UBC researchers.

The sponge reefs—constructed by living glass sponges growing on the skeletons of previous generations—can grow to the height of a six-storey building and were thought to have become extinct worldwide about 40 million years ago, until the discovery of  massive reefs 200 metres deep in Hecate Strait in northern B.C. in 1987 (although they had been observed as unexplained “mounds” on the floors of Queen Charlotte Sound and Hecate Strait during sonar surveys a few years previous).

At the time, the reefs were described by astonished scientists as “living dinosaurs”. German paleontologist Manfred Krautter was quoted as saying their discovery in B.C. waters “electrified” him and was “like discovering a herd of dinosaurs on land”, and the prehistoric constructs are often referred to as “Jurassic Park submerged”.

Subsequent dives by scientists in submersibles determined that they were up to 6,000 years old and covered a surface area of up to 700 square kilometres. It is theorized that the sponges, which are living marine animals, started building reefs there after B.C.’s most recent glaciation period scraped the ocean bottom clean more than 9,000 years ago.

Since the first discoveries, another 19 glass-sponge reefs have been found in the Strait of Georgia, part of what is often called the Salish Sea. An American geologist found other, specialized, reefs off the coast of Washington state in 2007.

The sponges use dissolved silica—glass, essentially—to build skeletons constructed of needlelike so-called spicules. Although glass sponges are common around the world, only in very rare cases do they form reefs, building new structures on top of the skeletons of dead sponges. The relatively accessible reefs found in Howe Sound are unique in the world for their shallow depth of less than 40 metres.

The UBC paper—published on May 18 in Scientific Reports, an open-access, peer-reviewed journal—detailed the results of an experiment initiated by Angela Stevenson, a postdoctoral fellow at UBC’s zoology department who is the study’s lead researcher. Stevenson was aided by scientists from Fisheries and Oceans Canada’s Pacific Biological Station in Nanaimo, Vancouver’s Ocean Wise Research Institute, and UBC’s department of botany.

Stevenson brought some examples of Aphrocallistes vastus—called the cloud sponge and one of three species of reef-building glass sponges found in B.C. waters—from Howe Sound to a UBC lab. Water temperature and acidity were then manipulated for a four-month study, resulting in the first successful long-term lab experiment involving living glass sponges.

““Their sheer size and tremendous filtration capacity put them at the heart of a lush and productive underwater system, so we wanted to examine how climate change might impact their survival,” Stevenson said in a June 1 UBC news release.

The researchers were monitoring the sponges’ durability, pumping ability, and skeletal strength. The results showed that the sponges experienced up to a 25 percent loss in tissue and a 50-percent reduction in pumpong capacity. Their bodies also became more elastic and lost about half their strength.

“Most worryingly, pumping began to slow within two weeks of exposure to elevated temperatures,” Stevenson noted.

Glass-sponge reefs are home to many marine creatures in B.C., including fish and giant Pacific octopuses.
Diane Reid/Ocen Wise

Glass sponges survive by pumping enormous volumes of water through their systems, filtering out the bacteria and plankton that they eat and purifying the surrounding seawater. It is estimated that the 19 reefs that are known to be in the Salish Sea can filter up to 100 billion litres of seawater every day, removing about 80 percent of the particles and microbes therein.

The Canadian Parks and Wilderness Society’s (CPAWS) B.C chapter, which advocates to protect glass-sponge reefs, says that 95 percent of seawater bacteria are filtered out by glass sponges and that a small reef of the sponges will filter and clean a volume of water every 60 seconds that would fill an Olympic-sized swimming pool.

Diver Glen Dennison above a Howe Sound glass-sponge reef.
Adam Taylor/Marine Life Sanctuaries Society

The reefs are protected by various conservation efforts in B.C’s deep northern waters and shallower Salish Sea depths, including federal marine protected areas in Hecate Strait and Queen Charlotte Sound and smaller buffer zones in Howe Sound and the Strait of Georgia. CPAWS says that research shows both measuers require expansion to fully protect the delicate structures from potential fishing and resource-exploration damage.

Borttom fishing, especially trawling, can devastate glass-sponge reefs, and suspended sediment can choke the sponges’ feeding filters and even kill them. Crab and prawn traps can damage or crush the sponge skeletons.

Jeff Marliave, an Ocean Wise senior researcher and paper coauthor, said in the release that more study is needed to understand how climate change might affect the reefs. “In Howe Sound, we want to figure out a way to track changes in sponge growth, size and area and area in the field so we can better understand potential climate implications at a larger scale. We also want to understand the microbial food webs that support sponges and how they might be influenced by climate cycles.”

Stevenson had a cautionary thought about what is required to guarantee the future safety of the reefs, whaich have been described as “international treasures”.

“When most people think about reefs, they think of tropical shallow-water reefs like the beautiful Great Barrier Reef in Australia,” Stevenson said. “But we have these incredible deep-water reefs in our own backyard in Canada. If we don’t do our best to stand up for them, it will be like discovering a herd of dinosaurs and then immediately dropping dynamite on them.”

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This bird can fly 160 kilometres without flapping its wings – CBC.ca

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A new study sheds light on just how efficiently the world’s largest soaring bird rides air currents to stay aloft for hours without flapping its wings.

The Andean condor has a wingspan stretching to three metres and weighs up to 15 kilograms, making it the heaviest soaring bird alive today.

For the first time, a team of scientists strapped recording equipment they called “daily diaries” to eight condors in South America’s Patagonia region to record each wingbeat over more than 250 hours of flight time.

Incredibly, the birds spent just one per cent of their time aloft flapping their wings, mostly during takeoff. One bird flew more than five hours, covering more than 160 kilometres, without flapping its wings.

“Condors are expert pilots — but we just hadn’t expected they would be quite so expert,” said Emily Shepard, a study co-author and biologist at Swansea University in Wales.

The results were published Monday in the journal Proceedings of the National Academy of Sciences.

“The finding that they basically almost never beat their wings and just soar is mind-blowing,” said David Lentink, an expert in bird flight at Stanford University, who was not involved in the research.

Researchers found Andean condors spent just one per cent of their time aloft flapping their wings, mostly during takeoff. One bird flew more than five hours, covering more than 160 kilometres, without flapping its wings. (Gonzalo Ignazi)

To birds, the sky is not empty, but a landscape of invisible features — wind gusts, currents of warm rising air, and streams of air pushed upward by ground features such as mountains.

Learning to ride air currents allows some birds to travel long distances while minimizing the exertion of beating their wings.

Scientists who study flying animals generally consider two types of flight: flapping flight and soaring flight. The difference can be compared to peddling a bicycle uphill, versus coasting downhill, said Bret Tobalske, a bird flight expert at the University of Montana, who was not involved in the study.

Past studies have shown that storks and osprey flap for 17 per cent and 25 per cent of their overland migratory flights, respectively.

The Andean condor’s extreme skill at soaring is essential for its scavenger lifestyle, which requires hours a day of circling high mountains looking for a meal of carrion, said Sergio Lambertucci, a study co-author and biologist at the National University of Comahue in Argentina.

“When you see condors circling, they are taking advantage of those thermal uplifts,” or rising gusts of warm air, he said.

Researchers say the Andean condor’s extreme skill at soaring is essential for its scavenger lifestyle, which requires hours a day of circling high mountains looking for a meal of carrion. (Facundo Vital)

The recording devices were programmed to fall off the birds after about a week.

Retrieving them wasn’t so easy.

“Sometimes the devices dropped off into nests on huge cliffs in the middle of the Andes mountains, and we needed three days just to get there,” said Lambertucci.

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Hope Mars mission: How to watch the UAE make history Tuesday – MSN Money

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The United Arab Emirates will head to Mars for the first time on Tuesday. From Tanegashima, a Japanese island in the north Pacific ocean, a Mitsubishi H-IIA booster will carry a car-sized probe known as “Al Amal,” or “Hope,” to space — and onto the red planet.






© Provided by CNET
The Hope probe (Al Amal) will circle Mars on a 55 day orbit, analyzing its atmosphere. MBRSC






© Mohammed bin Rashid Space Centre


The probe is expected to reach orbit around the red planet in early 2021. It’s designed to give a full picture of the Martian atmosphere, offering a holistic view of how Mars’ climate varies during the year. 

How to watch the Hope probe launch to Mars

The launch from Tanegashima, Japan, opens Tuesday, July 14, at 1:51 p.m. PT. It’ll launch on a Mitsubishi H-IIA booster. The rocket isn’t quite as famous as the likes of SpaceX’s Falcon 9 or Falcon Heavy rockets, but it does have a great launch history, with over 40 successful launches under its belt, mostly of Japanese satellite systems.

The Mohammed bin Rashid Space Centre will carry a livestream of the launch from Japan, which you can watch via this link. Or, tune into the livestream below:

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One big hope

Hope is the first interplanetary mission led by an Arab, Muslim-majority country and, if successful, will add another nation to the list of Martian explorers.  

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“The intent was not to put a message or declaration to the world,” Sarah Al Amiri, chair of the UAE Council of Scientists and deputy project manager for the Emirates Mars Mission, told CNET in March. “It was, for us, more of an internal reinforcement of what the UAE is about.”  The historic launch is set to be livestreamed across the globe. 

The satellite will study the connections between Mars’ lower and upper atmosphere and examine what causes the loss of hydrogen and oxygen into space. It’ll collect data for two years after achieving its orbit around Mars in February 2021. There’s an option to extend the mission to 2025.

Aboard Hope are three instruments which will enable the probe to study the Martian atmosphere more intensely. There’s a high-resolution camera known as the Emirates eXploration Imager (EXI), a UV imager known as the Emirates Mars Ultraviolet Spectrometer (EMUS), and a scanning infrared imager dubbed the Emirates Mars InfraRed Spectrometer (EMIRS).  

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New Class of Radio-Astronomical Objects Discovered: Odd Radio Circles | Astronomy – Sci-News.com

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An international team of astronomers has discovered an unexpected new class of radio-astronomical objects, consisting of a circular disk, which in some cases is limb-brightened, and sometimes contains a galaxy at its center. Named ‘Odd Radio Circles,’ these objects do not seem to correspond to any known type of astronomical object.

ASKAP radio continuum image of ORC 1 (contours) overlaid onto a DES 3-color composite image. Two galaxies of interest: ‘C’ lies near the center of ORC 1 and ‘S’ coincides with the southern radio peak. Image credit: Norris et al, arXiv: 2006.14805.

Circular features are well-known in radio-astronomical images, and usually represent a spherical object such as a supernova remnant, a planetary nebula, a shell around a star, or a face-on disk such as a protoplanetary disk or a star-forming galaxy.

They may also arise from imaging artifacts around bright astronomical objects.

Western Sydney University and CSIRO astronomer Ray Norris and his colleagues report the discovery of a class of circular feature in radio images that do not seem to correspond to any of these known types of object or artifact, but rather appear to be a new class of astronomical object.

“For brevity, and lacking an explanation for their origins, we dub these objects Odd Radio Circles (ORCs),” they said.

The researchers spotted three ORCs — named ORCs 1, 2 and 3 — in images from the Pilot Survey of the Evolutionary Map of the Universe, which is an all-sky continuum survey using the Australian Square Kilometre Array Pathfinder telescope (ASKAP).

A further radio source, called ORC 4, was discovered in archival observations of the galaxy cluster Abell 2142 taken with the Giant MetreWave Radio Telescope (GMRT).

All four ORCs are similar in displaying a strong circular symmetry and none of them have obvious counterparts in optical, infrared and X-ray wavelengths.

They differ in that two of them have a central galaxy while two do not, and three of them (ORCs 1, 2 and 4) consist of a partly filled ring while one (ORC 3) seems to be a uniform disk. There is also the puzzling fact that two of them are very close together, implying that these two ORCs have a common cause.

If the central galaxy in ORC 4 is associated with the ring, then the ring is 4.2 billion light-years away and has a size of 1.1 by 0.9 million light-years.

ASKAP radio continuum images of ORCs 2 and 3 from the Pilot Survey of the Evolutionary Map of the Universe and of ORC 4 from GMRT archival data. On the left are gray-scale images, with the synthesized beam shown in the bottom left corner, and radio contours overlaid onto DES optical images on the right. Image credit: Norris et al, arXiv: 2006.14805.

ASKAP radio continuum images of ORCs 2 and 3 from the Pilot Survey of the Evolutionary Map of the Universe and of ORC 4 from GMRT archival data. On the left are gray-scale images, with the synthesized beam shown in the bottom left corner, and radio contours overlaid onto DES optical images on the right. Image credit: Norris et al, arXiv: 2006.14805.

“We consider it likely that the ORCs represent a new type of object found in radio-astronomical images,” the scientists said.

“The edge-brightening in some ORCs suggests that this circular image may represent a spherical object, which in turn suggests a spherical wave from some transient event.”

“Several such classes of transient events, capable of producing a spherical shock wave, have recently been discovered, such as fast radio bursts, gamma-ray bursts, and neutron star mergers. However, because of the large angular size of the ORCs, any such transients would have taken place in the distant past.”

“It is also possible that the ORCs represent a new category of a known phenomenon, such as the jets of a radio galaxy or blazar when seen end-on, down the ‘barrel’ of the jet.”

“Alternatively, they may represent some remnant of a previous outflow from a radio galaxy.”

“However, no existing observations of this phenomenon closely resemble the ORCs in features such as the edge-brightening or the absence of a visual blazar or radio galaxy at the center.”

“We also acknowledge the possibility that the ORCs may represent more than one phenomenon,” they added.

“Further work is continuing to investigate the nature of these objects.”

The astronomers submitted their paper for publication in the journal Nature Astronomy.

_____

Ray P. Norris et al. 2020. Unexpected Circular Radio Objects at High Galactic Latitude. Nature Astronomy, submitted for publication; arXiv: 2006.14805

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