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Why astronomers are wondering whether Orion's shoulder will soon explode – CBC.ca

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The dramatic dimming of a giant star has astronomers wondering whether it’s getting ready to explode. 

Betelgeuse — the red shoulder on the left side in the constellation Orion — has dimmed by a factor of about two since October, a change that has never been documented before.

“We know that it’s the dimmest it’s been observed ever, based on the data we have,” said Stella Kafka, chief executive officer of the American Association of Variable Star Observers

What makes this development particularly intriguing to astronomers is that the star is slated to explode in spectacular fashion: a supernova. Astronomers estimate this will happen relatively soon — in astronomical terms anyway. It could be today, tomorrow or 100,000 years from now.

And when Betelgeuse goes supernova, astronomers estimate it will be as bright as the full moon and visible even during the day.

The tricky thing is that, because Betelgeuse is a red supergiant cloaked in a cloud of dust and gas, it’s difficult to accurately describe it.

It’s believed to be anywhere between 425 to 650 light years away, with a mass roughly 10 times that of the sun. It is also huge — likely 1,400 times larger than the sun. If it sat where the sun does, it would swallow all the inner planets, including Earth, Mars and even Jupiter. It’s also about 14,000 times more luminous than our comparatively small star.

But Betelgeuse is also a variable star, meaning its brightness rises and falls periodically. But we’ve never seen it like this.

“Maybe 300 years ago, Betelgeuse was dimmer than what we’re observing now, but we don’t have data,” Kafka said. 

This image, made with the European Southern Observatory’s Atacama Large Millimeter/submillimeter Array (ALMA) telescope, shows the red supergiant Betelgeuse — one of the largest known stars. If it were at the centre of our solar system, Betelgeuse would engulf Mercury, Venus, Earth, Mars and even Jupiter. (ALMA (ESO/NAOJ/NRAO)/E. O’Gorm)

 

So, does this dimming portend a potentially historic and magnificent explosion?

Maybe. Maybe not.

It’s not quite clear why exactly Betelgeuse dims periodically, but one of the possibilities is that, like the sun, it has cooler and hotter parts. If one of those cooler parts swung into our line of sight, that could make it seem like the star had dimmed.

In 2018, Betelgeuse had a couple of dips in its brightness, Kafka said. What we’re seeing now could be that same spot, or possibly another.

Plus, dimming isn’t necessarily indicative of an impending explosion.

There’s no telling what will happen next.

“I don’t even know if that’s the dimmest it’s going to get. This is an event that has been evolving,” Kafka said. “We’re still in the middle of it. Well, we’re still actually at the beginning of it. These kinds of massive stars move slowly. They take their sweet time.”

A history of supernovas

Astronomers spot supernovas somewhat regularly, though in other galaxies.

The last one in our galaxy that may have been observed from Earth was Cassiopeia A in 1680. 

Astronomers estimate that supernovas occur in galaxies like ours once every 100 years or so, though that doesn’t mean we will witness them all; they could be on the other side of the galaxy, for example, or hidden from view.

The supernova remnant Cassiopeia A as seen by the Chandra X-Ray Observatory. The blue dot in the centre of the image is identified as a young neutron star. (NASA/CXC/SAO; Optical: NASA/STScI; Infrared: NASA/JPL-Caltech/O. Krause)

A perfect example is a study published in 2008 that detected the remnant of a supernova in the Milky Way that was traced back roughly 140 years. It wasn’t visible to the naked eye, as it lay close to the centre of the galaxy and was obscured by dust and gas.

So we may be due for one soon.

No mutants

Kafka said there’s no need to panic: even if Betelgeuse were to explode, it wouldn’t obliterate life on Earth or turn us into mutants, though we would notice the blow of radiation it would deliver.

“What I will tell you is that it will be super interesting,” Kafka said.

“It will be an excellent opportunity to study a supernova in the making.”

The star could explode in two ways, she said. Either in two beams from its poles, or with a spherical, symmetrical explosion in all directions. If we were in the way of the beam-type explosion — which we’re not — or if Betelgeuse was a lot closer, we’d be in trouble.

But for now, you can carry on enjoying the holidays, if that’s what you were planning.

“We’re not going to die,” Kafka said. “But if you’re looking for an excuse to eat more this Christmas, go for it.”

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NASA's new $30M space toilet is smaller, better smelling and more female-friendly – CBC.ca

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Melissa McKinley has spent the last three years helping to build a cutting-edge piece of technology that will make life a lot easier for astronauts on space missions.

NASA’s new $30-million space toilet, the Universal Waste Management System (UWMS), will launch to the International Space Station (ISS) this weekend, where astronauts will test how well it works in micro-gravity. 

Designed with astronaut feedback in mind, the new toilet is lighter, smaller, better smelling and more gender-inclusive than the Russian-made toilet currently in use aboard the ISS. 

“It’s a fun project to work on because of the technical challenges, and because of the big impact on the crew. Obviously, going to the bathroom is something that the crew has to deal with multiple times a day,” McKinley, a systems project manager at NASA, told As It Happens guest host Helen Mann. 

“We have such a talented and technical team working on this. It has truly been exciting to see the challenges and solutions that this team has come up with.”

How does a space toilet work?

While toilets down here on Earth use water to flush away waste, space toilets use use air flow.

Feces is pulled away from the body and into a cannister for later disposal, while urine is sent to the ship’s recycling system to be converted into drinkable water.

“Obviously, that’s a vital part of the overall systems on board,” McKinley said.

The new toilet improves upon existing technology in a number of ways, and it was designed with the help of astronaut feedback to be more comfortable and easier to use, clean and maintain. 

“The project team is focused on doing the best job technically. And in order to do that, you have to have those frank conversations, and they become very, very commonplace,” McKinley said.

“The goal there for our team is to make it so that the crew can focus on other things they need to do during space travel and make this a more comfortable and convenient way for them to deal with these bodily functions.”

Answering the call of nature in microgravity isn’t easy, but NASA’s hoping to make it a little more pleasant for their ISS crew this week. (NASA)

One big complaint about the previous toilet design is that it “really wasn’t customized for the female experience,” McKinley said. “So this is a chance to customize it more for the female anatomy and more for their use.”

Current design is divided into two parts, with crew using a funnel and hose for peeing, and a seat for bowel movements. The UWMS is designed so that the funnel and seat can be used simultaneously. 

Another major factor is the smell.

Orion capsule engineering lead Jason Hutt, tweeted last month: “If you want to recreate that used spacecraft smell, take a couple dirty diapers, some microwave food wrappers, a used airsickness bag, & a few sweaty towels, put them in an old school metal trash can and let it bake in the summer sun for 10 days. Then open the [lid] & breathe deep.”

That shouldn’t be a problem with the UWMS, McKinley said. The new model comes with an odour bacteria filter. 

“It’s been said that the air coming out of the toilet is some of the nicest smelling air on the spacecraft,” she said.

But, perhaps, the most important upgrade is the reduced mass. 

The UWMS is 65 per cent smaller and 40 per cent lighter than the toilet currently aboard the ISS — which means more room for the astronauts, and a safer launch. 

The toilet was supposed to launch on Tuesday aboard a cargo capsule as part of a routine resupply mission, but was delayed due to weather. NASA now hopes to launch by the weekend. 

If all goes well, NASA also plans to install the toilet on Orion for a flight test that will send astronauts on a 10-day mission beyond the Moon and back.


Written by Sheena Goodyear. Interview produced by Sarah Peterson. 

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“Toxic or Habitable?” –The Hidden Lakes of Ultima Scopuli at Mars South Pole – The Daily Galaxy –Great Discoveries Channel

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"Toxic, or Prime for Life?" --The Buried Lakes of Ultima Scopuli at Mars South Pole

One of the myriad of unsolved mysteries about the Red Planet is why why ancient Mars had liquid water. Early in the planet’s history, Mars only received a third of the sunlight of present-day Earth, which shouldn’t be enough heat to maintain water. But in past, ancient millennia, huge rivers flowed across the planet’s surface, when its atmosphere was thicker and warmer, cutting gullies and channels on the silent, desolate landscape, unchanged for millions of years that are visible today to orbiting spacecraft. Scientists have long known that water was abundant on ancient Mars, but there has been no consensus on whether liquid water was common, or whether it was largely frozen in ice.

In 2013, planetary scientists at the European Space Agency released 3D images of the striking upper part of the Reull Vallis region of Mars, which reveal a 1500 kilometer long river running from the Promethei Terra Highlands to the vast Hellas basin. The image data from ESA’s Mars Express spacecraft shows that, at some points, the river bed is seven kilometers wide and 300 meters deep. The stereo cameras on board the satellite have also revealed “numerous tributaries” that fed the gigantic river. Today’s low atmospheric pressures on the Red Planet mean that any surface water would boil away. But recent discoveries reveal that water survives not frozen in polar ice caps and in subsurface ice deposits but also in a massive network of ancient buried lakes.

Mars ancient riversMars ancient rivers

Mars at One Billion –“Rainstorms & Huge Flowing Rivers”

In January of 2020, Caltech astronomers probed a mysterious feature at the South Pole of Mars –a massive deposit of CO2 ice and water ice in alternating strata, like the layers of a cake, shown at the top of the page, that extend to a depth of one kilometer, buried under a thin cover of CO2 ice. This strange feature was preceded in 2018 by discovery of evidence suggesting that far beneath the deeply frozen ice cap at Mars’s south pole lies a lake of liquid water—the first found on the Red Planet. Detected from orbit using ice-penetrating radar of Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS), the finding resembles the interconnected bodies of water buried under several kilometers of ice in Greenland and Antarctica, where a network of 400 lakes have been detected.

“The Death of Mars” –Pluto-Size Asteroid Ignited Ancient Climate Change

MARSIS, an instrument on the European Space Agency’s Mars Express orbiter, which launched in 2003, beams down pulses of radio waves and listens for reflections. Some of the waves bounce off the surface, but others penetrate up to 3 kilometers and can be reflected by sharp transitions in the buried layers, such as going from ice to rock.

Several years into the mission, MARSIS scientists began to see small, bright echoes under the south polar ice cap—so bright that the reflection could indicate not just rock underlying the ice, but liquid water. The researchers doubted the signal was real, however, because it appeared in some orbital passes but not others.

“Ice Age Mars” –Challenges a Once ‘Warm and Wet’ Red Planet

The spacecraft’s computer was averaging across pixels to reduce the size of large data streams—and in the process, smoothing away the bright anomalies. “We were not seeing the thing that was right under our noses,” says Roberto Orosei, a principal investigator (PI) for MARSIS at the Italian National Institute for Astrophysics in Bologna.

“It’s a very exciting result: the first indication of a briny aquifer on Mars,” said geophysicist David Stillman of Southwest Research Institute in Boulder, Colorado. The findings, if confirmed, would mark the detection of the largest body of liquid water on Mars reported Marina Koren in The Atlantic..

Huge Lake Detected Under Mars’ South Pole –“We Were Not Seeing the Thing That was Right Under Our Noses”

A lake of liquid water surrounded by smaller ponds may be buried under 1400 meters of ice near the south pole of Mars reports Nature. New measurements offer more evidence of its existence, according to Elena Pettinelli at Roma Tre University in Italy and her colleagues who used the MARSIS radar instrument then applied criteria that were used to search for buried lakes in Greenland, –where New research has increased the number of known lakes lurking beneath the ice sheet from just four to a total of 60–to examine an area called Ultima Scopuli near the Red Planet’s south pole.

The researchers spotted a liquid lake measuring about 20-by-30 kilometers, along with at least three smaller ponds, each a few kilometers across. But the resolution of the radar measurements wasn’t high enough to determine their depth.

“It was probably originally a larger, wet area, and this is the remnant of that in smaller ponds,” says Pettinelli. For the water to remain liquid at the frigid temperatures, her team suggests that it is most likely a salty brine.

“There are bacteria that can live in very awkward situations,” says Pettinelli. “In Antarctica, they found bacteria living happily in the water of the underground lakes and between the crystals of the ice, and Antarctica is our closest analogue to Mars.”

The Daily Galaxy via Science,  Nature, New Scientist, The Atlantic

Image credit top of page: the ice-capped Martian south pole, pictured here by the Mars Express spacecraft that also carries the MARSIS radar instrument. (ESA/DLR/FU Berlin / Bill Dunford)

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MIT Researchers Say Their Fusion Reactor Is “Very Likely to Work” – Futurism

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A team of researchers at MIT and other institutions say their “SPARC” compact fusion reactor should actually work — at least in theory, as they argue in a series of recently released research papers.

In a total of seven papers penned by 47 researchers from 12 institutions, the team argues that no unexpected impediments or surprises have shown up during the planning stages.

In other words, the research “confirms that the design we’re working on is very likely to work,” Martin Greenwald, deputy director of MIT’s Plasma Science and Fusion Center and project lead, told The New York Times.

Fusion power remains elusive, but the tech promises to one day become a safe and clean way of producing energy by fusing atomic nuclei together like the Sun. Despite almost a century of research, though, nobody has managed to pull it off yet.

SPARC, one of the largest privately funded project of its kind in the field, would be a first of its kind: a “burning plasma” reactor that fuses hydrogen isotopes to form helium, with no other input of energy needed.

Thanks to progress in the field of superconducting magnets, the team hopes to achieve the same performance as far larger reactors, such as the gigantic ITER (International Thermonuclear Experimental Reactor) reactor, which started assembly in July.

The magnets are used to contain the extremely hot and high pressure reactions going on inside the reactor, one of fusion’s greatest challenges.

According to the team’s calculations, SPARC should be able to produce twice as much fusion energy compared to the amount needed to generate the reaction. That would be a massive jump, since no researchers have managed to break even yet.

In fact, in the papers, the researchers note it could be theoretically possible to generate ten times the amount — though there’s plenty of work ahead before they could say that for sure.

The MIT team is hoping to construct its compact reactor over the next three to four years, with the eventual goal of generating electricity starting in 2035, the Times reports.

“What we’re trying to do is put the project on the firmest possible physics basis, so that we’re confident about how it’s going to perform, and then to provide guidance and answer questions for the engineering design as it proceeds,” Greenwald said in an official statement.

READ MORE: Compact Nuclear Fusion Reactor Is ‘Very Likely to Work,’ Studies Suggest [The New York Times]

More on fusion: Scientists Start Construction of World’s Largest Fusion Reactor

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