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Mars Express Spots Chaotic Terrain near Valles Marineris | Planetary Science, Space Exploration – Sci-News.com

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The High Resolution Stereo Camera (HRSC) onboard ESA’s Mars Express orbiter has imaged a fascinating landscape near the major canyon system of Valles Marineris on the Red Planet.

This image from the High Resolution Stereo Camera (HRSC) aboard ESA’s Mars Express shows craters, valleys and chaotic terrain in Pyrrhae Regio, Mars. Chaotic terrain forms as a shifting subsurface layer of melting ice and sediment causes the surface above to collapse. In the chaotic terrain seen here, ice has melted, the resulting water drained away, and a number of disparate broken blocks have been left standing in now-empty cavities (which once hosted ice). This image comprises data gathered by HRSC on August 3, 2020. Image credit: ESA / DLR / FU Berlin / CC BY-SA 3.0 IGO.

Valles Marineris is a vast canyon system that runs along the Martian equator just east of the Tharsis region.

It is 4,000 km (2,500 miles) long and reaches depths of up to 7 km (4 miles) — roughly 10 times longer and 5 times deeper than the Grand Canyon in Arizona.

It comprises myriad smaller rifts, channels, outflows, fractures and signs of flowing material (such as water, ice, lava or debris).

Valles Marineris is an unmissable scar on the face of Mars, and thought to have formed as the planet’s crust was stretched by nearby volcanic activity, causing it to rip and crack open before collapsing into the deep troughs we see today.

These troughs have been further shaped and eroded by water flows, landslides, and other erosive processes, with spacecraft including Mars Express spying signs that water existed in parts of Valles Marineris in the relatively recent past.

Perspective view of chaotic terrain in Pyrrhae Regio, Mars. Image credit: ESA / DLR / FU Berlin / CC BY-SA 3.0 IGO.

Perspective view of chaotic terrain in Pyrrhae Regio, Mars. Image credit: ESA / DLR / FU Berlin / CC BY-SA 3.0 IGO.

The new image from Mars Express’ HRSC instrument shows ‘chaotic terrain’ in Pyrrhae Regio — a region located south of Eos Chasma, an eastern branch of the Valles Marineris system.

A scattering of impact craters, formed as incoming bodies from space collided with Mars’ surface, can be seen to the left of the frame.

The floor of the largest and uppermost basin spans about 40 km (25 miles), and contains some fractures and markings that formed just after the crater itself.

Hot, molten rock is thought to have been thrown up during the crater-forming collision, after which it cooled and settled to form the scar-like features visible here.

Towards the middle of the frame, the surface is relatively smooth and featureless — however, two broad channels have worked their way through the landscape, and can be seen as meandering, branching indentations in the surrounding terrain.

The valleys are attached at their rightward end to the real star of the image: a sunken, uneven, scarred patch of ground known as chaotic terrain.

Chaotic terrain, as the name suggests, looks irregular and jumbled, and is thought to form as sub-surface ice and sediment begins to melt and shift.

This shifting layer causes the surface above to collapse — a collapse that can happen quickly and catastrophically as water drains away rapidly through the Martian regolith.

Ice can be triggered to melt by heating events such as volcanic lava flows, subsurface magmatism, impacts by large meteorites, or changes in climate.

In the chaotic terrain seen here, ice has melted, the resulting water drained away, and a number of disparate broken blocks have been left standing in now-empty cavities.

Remarkably, the floors of these cavities lie some 4 km (2.5 miles) below the flatter ground near the craters to the left.

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B.C. researchers find evidence of ancient predatory sand worms that were two metres long – Calgary Herald

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The trace fossils showed feather-like structures around the upper parts of the burrows, which the researchers believe would have been caused by the worms dragging their struggling prey under the ocean floor to eat them.

The lower, horizontal part of the burrow. Photo by Yu-Yen Pan /Simon Frazer University

The study’s lead author, earth sciences student Yu-Yen Pan, said the giant burrows are much larger than other trace fossils of ocean worms found in the past.

“Compared to other trace fossils which are usually only a few tens of centimetres long, this one was huge; two-metres long and two to three centimetres in diameter,” she said in a press release. “The distinctive, feather-like structures around the upper burrow were also unique and no previously studied trace fossil has shown similar features.”

The researchers say that these worms likely would have fed similarly to the bobbit worm, often called the “sand striker.”

Bobbit worms wait in their burrow for unsuspecting prey, then explode upwards, grabbing the prey in their mouths and pulling them back down into the sediment.

Field excursion at Yehliu, Taiwan. Photo by Masakazu Nara /Simon Frazer University

The researchers also found evidence that led them to believe the worms secreted mucus after each feeding that rebuilt and reinforced their burrows, allowing them to lie in wait for their next victim without being seen.

Pan and an international team that studies the ancient sea floor has named the homes of these worms Pennichnus formosae.

According to the study, previous research on Eunicid polychaetes, the family that these ancient worms and bobbit worms belong to, was limited because they only stuck a small portion of their bodies out from the ocean floor.

These trace fossils have allowed researchers to better understand the activity and habits of the ancient species.

Predatory ocean worms have existed for over 400 million years, and while these ancient burrows are long when compared to others that had previously been studied, giant marine worms are not just creatures of the ancient past.

Bobbit worms can grow up to three metres long themselves, and lay in their burrows just beneath the ocean floor today.

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13 new North Atlantic right whale calves recorded this season – CBC.ca

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Thirteen North Atlantic whale calves have been spotted off the coast of the southern United States — more than the number born in a single winter since 2016.

The calves, recorded only about halfway through the calving season, are reason for “guarded optimism” about the endangered whale’s population, a researcher says. 

“In 2018 we didn’t have any calves born and we’ve had ten or less in most of the previous five years,” said Philip Hamilton, a research scientist with the Anderson Cabot Centre for Ocean Life at the New England Aquarium. “So that’s very positive news.” 

Philip Hamilton, a research scientist with the Anderson Cabot Centre for Ocean Life at the New England Aquarium, says he’s guardedly optimistic about the 13 North calves spotted this year. (Submitted by Philip Hamilton)

Calving season for North Atlantic right whales typically runs from the start of December to the end of March. So, it’s possible this could be the first year in a long time the population hits a supposed reproduction average. 

Scientists expect 23 calves a year

Hamilton said that given the current state of the whale population, scientists would expect an average of around 23 calves a year. That hasn’t happened in years, likely because of the stress whales are experiencing finding enough food.  

The North Atlantic right whale population have recently moved into unfamiliar and more hazardous waters in search of a dwindling food supply.

Hamilton says that in recent years, North Atlantic right whales haven’t reached an expected birth rate of 20 or more calves per season. (Florida Fish and Wildlife Conservation Commission, taken under NOAA permit 20556-01)

While there are some first-time mothers with calves this year, several of the mothers haven’t reproduced in a decade. 

“On average a right whale should be able to give birth every three or four years, and some of the mothers that are giving birth this year have gone 10 or 11 years without calving,” said Hamilton. “So, there’s a backlog of whales that should be able to calve and it’s really encouraging that they are.” 

‘We need to stop killing these animals’

Hamilton says he is optimistic about this year’s calving season, but says it’s important to put things into context. 

“We really need to stop killing these animals,” said Hamilton. “We’ve had 32 deaths between 2017 … we know that we’re missing probably two-thirds of the deaths.” 

Hamilton estimates that as many as 100 of the whales may have died in the last four years. 

Necropsies determined that many of them were killed as a result of blunt trauma likely due to being struck by passing ships. Entanglement in fishing gear has been cited as a cause of deaths.

Both Canada and the United States have implemented restrictions to curb the number of North Atlantic right whale deaths in recent years. 

“Clearly we’re not doing enough,” Hamilton said. “Not enough, when we have a population of around 350.” 

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Starlink satellite internet grants instant sign-up for eligible Canadians – Saskatoon StarPhoenix

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In a CBC article, some Starlink subscribers have reported service speeds of up to 150Mbps.

The Canadian Radio-Television and Telecommunication Commission (CRTC) granted Starlink’s operator, SpaceX, a Basic International Telecommunications Service (BITS) license in October 2020. The license allows SpaceX to provide telecommunication services in Canada but does not allow it to operate as an internet service provider within the issuing nation.

Related:

SpaceX granted basic telecom license in Canada  

Starlink says it aims to establish a global network by using a massive constellation of satellites. The satellites float at low earth orbit, which both cuts down on signal latency and can more easily return to earth once they’re decommissioned. But stargazers are worried that the massive amount of satellites could obscure the view of the night sky.

The company has expressed a keen interest in providing internet service to rural and underserved areas in Canada and the United States. It’s currently extending beta testing offers in Canada, U.S. and U.K.

Starlink says it has launched 955 satellites so far.

The post Starlink satellite internet grants instant sign-up for eligible Canadians first appeared on IT World Canada.

This section is powered by IT World Canada. ITWC covers the enterprise IT spectrum, providing news and information for IT professionals aiming to succeed in the Canadian market.

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