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NASA watches as weird 'dent' in Earth's magnetic field splits in two – Space.com

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There’s something very strange happening high above South America and the nearby Atlantic Ocean, and NASA is on the case.

Meet the South Atlantic Anomaly, a strange dent in Earth’s magnetic field that is growing and splitting. It’s been there for decades, but over time the anomaly has slowly changed. Although you’d never notice anything was wrong from the ground, for satellites, changes to the magnetic field that envelopes Earth can be a big deal — hence NASA’s interest in the anomaly and its activities.

The connection comes because the magnetic field blocks charged particles spewed out by the sun from reaching Earth. But at the South Atlantic Anomaly, the field is dented, lowering the protective barrier above that part of Earth. The lower barrier means that more radiation bombards satellites as they fly over this region, triggering occasional shutdowns to avoid potential damage to the hardware, according to a NASA statement.

Video: South Atlantic Anomaly in Earth’s magnetic field described in detail
Related: Earth’s magnetic field booms like a drum, but no one can hear it 

An artist’s depiction of Earth’s magnetic field, with the sun in the background. (Image credit: NASA’s Goddard Space Flight Center)

The International Space Station is one of the many spacecraft that fly through the anomaly, but it carries extra shielding to protect the astronauts who live and work in orbit from radiation. Other spacecraft that fly through the anomaly send NASA valuable observations about how the feature is changing, like the Ionospheric Connection Explorer (ICON), which the agency launched last year in part to monitor the weak spot in the field after the retirement of its Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX) mission in 2012. Among other changes, those observations have shown that the “dent” is moving westward and splitting in two.

These observations are valuable because of the complexity of studying the magnetic field, which traces its roots to liquid metal moving within Earth’s core, then is shaped by a range of phenomena as it ripples out from the center of the planet, according to NASA. 

Those interactions mean that more data about changes in the magnetic field can lead to a host of valuable results — not just a better understanding of what the anomaly is doing now in order to warn approaching satellites, but also more nuanced models of what’s happening deep inside the Earth, and of course, more accurate predictions of how the anomaly will change into the future.

“Even though the SAA [South Atlantic Anomaly] is slow-moving, it is going through some change in morphology, so it’s also important that we keep observing it by having continued missions,” Terry Sabaka, a geophysicist at NASA’s Goddard Space Flight Center in Maryland, said in the statement. “Because that’s what helps us make models and predictions.”

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

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BREAKING | 24 new cases of COVID-19 in Niagara – Newstalk 610 CKTB (iHeartRadio)

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Niagara Region Public Health are reporting 24 new cases of COVID-19 in the region.

This is the highest single day increase of cases since June 3rd, which saw 40 new cases in the region.

Currently, Niagara has 77 active cases of the virus, and five active outbreaks.

To see the full details from Niagara Region Public Health, click here.

Ontario reported 491 new cases today.

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A physicist says new math proves paradox-free time travel is possible – SlashGear

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Time travel has been the staple science fiction books and movies for many years. Most who have read or watched content focusing on time travel knows about the paradox issue. Perhaps the best example is the 80s classic “Back to the Future,” where Marty accidentally prevents his parents from meeting and has to fix his error before he’s wiped out of existence.

Time travel is something that scientists and physicists have considered for many years. A physics student named Germain Tobar from the University of Queensland in Australia says that he has figured out the math that would make time travel viable without paradoxes. According to Tobar, classical dynamics says if you know the state of the system at a particular time, it can tell you the entire history of the system.

His calculations suggest that space-time may be able to adapt itself to avoid paradoxes. One example is a time traveler who journeys into the past to stop a disease from spreading. If the mission were successful, there would’ve been no disease for the time traveler to go back and try and prevent. Tobar suggests that the disease would still spread in some other way, through different route or method, removing the paradox.

He says whatever the time traveler did, the disease wouldn’t be stopped. Tobar’s work is highly complicated but is essentially looking at deterministic processes on an arbitrary number of regions in the space-time continuum. It’s demonstrating how closed timelike curves, which Einstein predicted, can fit in with the rules of free will and classical physics.

Tobar’s research supervisor is physicist Fabio Costa from the University of Queensland. Costa says that the “maths checks out,” further noting that the results are the stuff of science fiction. The new math suggests that time travelers can do what they want, and paradoxes are not possible. Costa says that events will always adjust themselves to avoid any inconsistency.

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We May Finally Know What Life on Earth Breathed Before There Was Oxygen – ScienceAlert

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Billions of years ago, long before oxygen was readily available, the notorious poison arsenic could have been the compound that breathed new life into our planet.

In Chile’s Atacama Desert, in a place called Laguna La Brava, scientists have been studying a purple ribbon of photosynthetic microbes living in a hypersaline lake that’s permanently free of oxygen.

“I have been working with microbial mats for about 35 years or so,” says geoscientist Pieter Visscher from the University of Connecticut.

“This is the only system on Earth where I could find a microbial mat that worked absolutely in the absence of oxygen.”

Microbial mats, which fossilise into stromatolites, have been abundant on Earth for at least 3.5 billion years, and yet for the first billion years of their existence, there was no oxygen for photosynthesis.

How these life forms survived in such extreme conditions is still unknown, but examining stromatolites and extremophiles living today, researchers have figured out a handful of possibilities. 

While iron, sulphur, and hydrogen have long been proposed as possible replacements for oxygen, it wasn’t until the discovery of ‘arsenotrophy‘ in California’s hypersaline Searles Lake and Mono Lake that arsenic also became a contender.

Since then, stromatolites from the Tumbiana Formation in Western Australia have revealed that trapping light and arsenic was once a valid mode of photosynthesis in the Precambrian. The same couldn’t be said of iron or sulphur.

Just last year, researchers discovered an abundant life form in the Pacific Ocean that also breathes arsenic. 

Even the La Brava life forms closely resemble a purple sulphur bacterium called Ectothiorhodospira sp., which was recently found in an arsenic-rich lake in Nevada and which appears to photosynthesise by oxidising the compound arsenite into a different form -arsenate.

While more research needs to verify whether the La Brava microbes also metabolise arsenite, initial research found the rushing water surrounding these mats is heavily laden with hydrogen sulphide and arsenic.

If the authors are right and the La Brava microbes are indeed ‘breathing’ arsenic, these life forms would be the first to do so in a permanently and completely oxygen-free microbial mat, similar to what we would expect in Precambrian environments.

As such, its mats are a great model for understanding some of the possible earliest life forms on our planet. 

While genomic research suggests the La Brava mats have the tools to metabolise arsenic and sulphur, the authors say its arsenate reduction appears to be more effective than its sulfate reduction.

Regardless, they say there’s strong evidence that both pathways exist, and these would have been enough to support extensive microbial mats in the early days of life on Earth.

If the team is right, then we might need to expand our search for life forms elsewhere.

“In looking for evidence of life on Mars, [scientists] will be looking at iron and probably they should be looking at arsenic also,” says Visscher.

It really is so much more than just a poison.

The study was published in Communications Earth and Environment

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