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Another look at possible under-ice lakes on Mars: They’re still there – Ars Technica

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In recent decades, we’ve become aware of lots of water on Earth that’s deep under ice. In some cases, we’ve watched this water nervously, as it’s deep underneath ice sheets, where it could lubricate the sheets’ slide into the sea. But we’ve also discovered lakes that have been trapped under ice near the poles, possibly for millions of years, raising the prospect that they could harbor ancient ecosystems.

Now, researchers are applying some of the same techniques that we’ve used to find those under-ice lakes to data from Mars. And the results support an earlier claim that there are bodies of water trapped under the polar ice of the red planet.

Spotting liquids from orbit

Mars clearly has extensive water locked away in the forum of ice, and some of it cycles through the atmosphere as orbital cycles make one pole or the other a bit warmer. But there’s not going to be pure liquid water on Mars—the temperatures just aren’t high enough for very long, and the atmospheric pressures are far too low to keep any liquid water from boiling off into the atmosphere.

Calculations suggest, however, that liquid water is possible on Mars—just not on the surface. With enough dissolved salts, a water-rich brine could remain liquid at the temperatures prevalent on Mars—even in the polar areas. And if it’s trapped under the Martian surface, there might be enough pressure to keep it liquid despite the thin atmosphere. That surface could be Martian soil, and people are thinking about that possibility. But the surface could also be one of the ice sheets we’ve spotted on Mars.

That possibility helped motivate the design of the MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) on the Mars Express orbiter. MARSIS is a radar device that uses wavelengths that water ice is transparent to. As a result, most of the photons that come back to the instrument are reflected by the interface between ice and something else: the atmosphere, the underlying bedrock, and potentially any interface between the ice and a liquid brine underneath it.

And that’s what the original results, published in 2018, seemed to indicate. In an area called Ultimi Scopuli near Mars’ south pole. The researchers saw a bright reflection, distinct from the one caused by the underlying bedrock, at some specific locations under the ice. And they interpreted this as indicating a boundary between ice and some liquid brines.

Now with more data

Two things have changed since those earlier results were done. One is that Mars Express has continued to pass over Mars’ polar regions, generating even more data for analysis. The second is that studies of ice-covered lakes on Earth have also advanced, with new ones identified from orbit using similar data. So some of the team behind the original work decided it was time to revisit the ice sheets at Ultimi Scopuli.

The analysis involves looking at details of the photons reflected back to the MARSIS instrument from a 250 x 300 square kilometer area. One aspect of that is the basic reflectivity of the different layers that can be discerned from the data. Other aspects of the signal can tell us about how smooth the surface of the reflective boundaries are and whether the nature of the boundary changes suddenly.

For example, the transition from an ice-bedrock boundary to an ice-brine one would cause a sudden shift from a relatively weak, uneven signal to a brighter and smoother one.

The researchers generated separate maps of the intensity and the smoothness of the signal and found that the maps largely overlapped, giving them confidence that they were identifying real transitions in the surfaces. A separate measure of the material (called permittivity) showed that it was high in the same location.

Overall, the researchers found that the largest area that’s likely to have water under the ice as about 20 by 30 kilometers. And it’s separated by bedrock features from a number of similar but smaller bodies. Calling these bodies “lakes” is speculative, given that we have no idea how deep they are. But the data certainly is consistent with some sort of under-ice feature—even if we use the standards of detection that have been used for under-ice lakes on Earth.

How did that get there?

The obvious question following the assumption that these bodies are filled with a watery brine is how that much liquid ended up there. We know that these salty solutions can stay liquid at temperatures far below the freezing point. But the conditions on Mars are such that most of minimum temperatures for water to remain liquid are right at the edge of the possible conditions at the site of the polar ice sheets. So some people have suggested geological activity as a possible source of heat to keep things liquid.

That’s not necessarily as unlikely as it may sound. Some groups have proposed that some features indicate that there was magma on the surface of Mars as recently as recently as 2 million years ago. But the researchers here argue that if things are on the edge of working under current climate conditions, there’s no need to resort to anything exceptional.

Instead, they suggest that the sorts of salts we already know are present on Mars can absorb water vapor out of the thin Martian atmosphere. Once formed, these can remain liquid down to 150 Kelvin, when the local temperatures at Ultimi Scopuli are likely to be in the area of 160 Kelvin and increase with depth.

And if that’s true, there could be liquid in many more locations at Mars’ poles. Not all of them are as amenable to orbital imaging as Ultimi Scopuli, but it’s a safe bet that this team will try to find additional ones.

Nature Astronomy, 2020. DOI: 10.1038/s41550-020-1200-6 (About DOIs).

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There will be a blue Hunter's Moon this Halloween – Yahoo Canada Sports

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Full moon and clouds at nightFull moon and clouds at night

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The October full moon is known as a Hunter’s Moon (Getty)
<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="Appropriately for the spookiest night of the year, there’ll be something unusual going on in the sky this Halloween – a blue Hunter’s Moon.&nbsp;” data-reactid=”32″>Appropriately for the spookiest night of the year, there’ll be something unusual going on in the sky this Halloween – a blue Hunter’s Moon

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="The moon will not (sadly) be blue, but it’s the second full moon in the month which makes it a blue moon (by some definitions at least, see below).&nbsp;” data-reactid=”33″>The moon will not (sadly) be blue, but it’s the second full moon in the month which makes it a blue moon (by some definitions at least, see below). 

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="Full moons are separated by 29 days, NASA says, and most months are 30 or 31 days long, so a “blue moon” happens every two and a half years on average.&nbsp;” data-reactid=”34″>Full moons are separated by 29 days, NASA says, and most months are 30 or 31 days long, so a “blue moon” happens every two and a half years on average. 

Full moons occur when the moon appears as a full circle in the sky, when the whole side of the moon facing the Earth is lit up by the sun.

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="Read more: Five moon myths (and how to disprove them yourself)&nbsp;” data-reactid=”36″>Read more: Five moon myths (and how to disprove them yourself) 

The moon will be full at 2.49pm on October 31, according to Royal Museums Greenwich. 

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="A blog post at Royal Museums Greenwich explains, “It may at first seem odd to think of a full Moon occurring during daylight hours.” data-reactid=”38″>A blog post at Royal Museums Greenwich explains, “It may at first seem odd to think of a full Moon occurring during daylight hours.

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="“The reason this happens is that the time refers to the exact moment when the Sun and Moon are aligned on opposite sides of the Earth.

“This moment is known as the ‘syzygy’ of the Sun-Earth-Moon system, and can happen at any time day or night.”” data-reactid=”39″>“The reason this happens is that the time refers to the exact moment when the Sun and Moon are aligned on opposite sides of the Earth.

“This moment is known as the ‘syzygy’ of the Sun-Earth-Moon system, and can happen at any time day or night.”

NASA expert Gordon Johnston explains that American names for Full Moons are derived from Native American folklore.

Johnston writes, “The Maine Farmer’s Almanac first published Native American names for the full Moons in the 1930s. 

This image was taken in Tuam county galway. Ireland.This image was taken in Tuam county galway. Ireland.

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Blue moons, despite the name, are not actually blue. Stock, Galway, Ireland (Getty)

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="“Over time these names have become widely known and used.

“The Hunter’s Moon is the full Moon after the Harvest Moon. According to the Farmer’s Almanac, with the leaves falling and the deer fattened, it is time to hunt.&nbsp;” data-reactid=”62″>“Over time these names have become widely known and used.

“The Hunter’s Moon is the full Moon after the Harvest Moon. According to the Farmer’s Almanac, with the leaves falling and the deer fattened, it is time to hunt. 

“Since the harvesters have reaped the fields, hunters can easily see the animals that have come out to glean (and the foxes that have come out to prey on them). 

“The earliest use of the term “Hunter’s Moon” cited in the Oxford English Dictionary is from 1710.”

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="Read more: What is a supermoon?&nbsp;” data-reactid=”65″>Read more: What is a supermoon? 

Strictly speaking, the definition of a “blue moon” as the second full moon in a given month is wrong – but it is now widely used, says Royal Museums Greenwich. 

Royal Museums Greenwich writes, ‘Traditionally the definition of a blue moon is the third full Moon in an astronomical season containing four full moons. The astronomical seasons begin and end at the equinoxes and solstices (e.g. the winter season begins at the winter solstice and ends at the spring equinox, the spring season begins at the spring equinox and ends at the summer solstice and so on).”

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="“Another definition of the blue moon, perhaps the more commonly used due to its simplicity, is actually a mistake, made in the 1940s and perpetuated by radio shows and the Trivial Pursuit board game through the 1980s.

“This definition describes the blue moon as the second full Moon in any calendar month with two full moons.”” data-reactid=”68″>“Another definition of the blue moon, perhaps the more commonly used due to its simplicity, is actually a mistake, made in the 1940s and perpetuated by radio shows and the Trivial Pursuit board game through the 1980s.

“This definition describes the blue moon as the second full Moon in any calendar month with two full moons.”

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'Massive' coral reef taller than the Empire State Building discovered in Australia – CTV News

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A “massive” new reef measuring 500 metres has been discovered in Australia’s Great Barrier Reef, making it taller than some of the world’s highest skyscrapers.

Scientists found the detached reef, which is the first to be discovered in more than 120 years, in waters off North Queensland while on an expedition aboard research vessel Falkor, ocean research organization Schmidt Ocean Institute announced Monday.

The reef was first discovered on October 20, as scientists completed an underwater mapping of the seafloor of the northern Great Barrier Reef.

At 500 metres high, it is taller than the Empire State Building (381 metres to the top floor), the Sydney Tower (305 metres) and the Petronas Twin Towers (451.9 metres.)

Using an underwater robot named SuBastian, the team explored the reef on Sunday, and live streamed footage of the exploration.

Experts say that the base of the “blade-like” reef measures 1.5 kilometres wide, rising 500 metres to its shallowest depth of 40 metres below the ocean surface.

There are seven other tall detached reefs in the area, including the reef at Raine Island — a significant green turtle nesting site.

Robin Beaman, who led the expedition, said he was “surprised” by the discovery.

“To not only 3D map the reef in detail, but also visually see this discovery with SuBastian is incredible,” he said in a statement.

“This unexpected discovery affirms that we continue to find unknown structures and new species in our ocean,” Wendy Schmidt, co-founder of Schmidt Ocean Institute, said in a statement.

“The state of our knowledge about what’s in the ocean has long been so limited. Thanks to new technologies that work as our eyes, ears and hands in the deep ocean, we have the capacity to explore like never before. New oceanscapes are opening to us, revealing the ecosystems and diverse life forms that share the planet with us.”

The Great Barrier Reef, the world’s largest coral reef, covers more than 214,000 square kilometres and is home to more than 1,500 species of fish, 411 species of hard corals and dozens of other species.

But the reef is facing a crisis — recent studies have shown that it has lost 50% of its coral populations in the last three decades, with climate change a key driver of reef disturbance.

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Surrey vet offers tips as Canada reports first COVID-19 case in dog in Ontario – News 1130

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SURREY (NEWS 1130) – As Canada’s first case of COVID-19 among dogs is reported in Ontario, a Surrey-based vet is providing some advice to pet owners who may have concerns.

Dr. Sajjid Ijaz with Lifetime Veterinary Clinic says research on COVID-19 in pets is still evolving, but at this point, there’s little evidence to suggest dogs can transmit the virus to humans.

He notes many owners have flagged their COVID-19 concerns with him and his staff over the past few months.

“Obviously, at this point because we do not have any data to give any concrete answers to them, so, we have just been telling them to be careful about going out of their own bubble, as far as their own personal self, as well as the pets themselves. So what we’ve been telling them is to try and limit the pet access to dog parks and all that stuff, and be careful about it,” he explains.

Ontario dog tests positive for COVID-19

A dog in Ontario’s Niagara area has been identified as the first canine to test positive for COVID-19 in Canada. Experts have said this isn’t cause for panic.

The dog apparently belongs to a household where four people tested positive for COVID-19.

Experts told the Toronto Star the dog “had no symptoms and a low viral load, suggesting that dogs remain at relatively low risk of becoming gravely ill or passing on COVID to others.”

Ijaz says while they’re not pushing that message too hard, he and his staff want pet owners to continue to be smart.

Pets and your social bubble

Because of the uncertainty around how the coronavirus is transmitted among pets, Ijaz says it’s wise to apply the same advice to pets when it comes to humans and their social bubbles.

“So, yes, I’ve been telling my clients to limit access, not just totally isolate them, but just to be smart about it,” he explains.

Ijaz understands that pets are often a big part of any family, which is why he believes it’s best to be safe rather than sorry.

“As much as we can limit the bubble, that will help,” he says, adding your social bubble shouldn’t exclude these animals.

According to the World Organisation for Animal Health, there’s been no report of pets spreading COVID-19 to people. There have been reports of possible transmission from mink at a farm in the Netherlands to humans, however, the federal government says this is still being studied.

-With files from 680 NEWS

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