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The exoplanet closest to us could be crawling with life—except it gets blasted with lethal X-rays – SYFY WIRE

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While we’re pretty sure the moon is dead and Mars doesn’t look too promising for any life-forms (except that human colony Elon Musk is planning), we may have to look beyond our solar system.

Proxima b is the closest exoplanet to Earth and a contradiction in itself. Some astronomers have found it potentially habitable while others have blasted it for the intense X-rays it constantly gets pelted with by the star it orbits, Proxima Centauri. The planet was first detected 4 light years away by the HARPS spectrograph, but has finally been confirmed to be a real celestial body by an international team of scientists using the more advanced ESPRESSO spectrograph. Their research was recently published in Astronomy and Astrophysics. Now that we’re positive Proxima b exists, let the habitability arguments begin.

It sounds like Proxima b likes to live dangerously, since it orbits 20 times closer to its star than the distance at which Earth journeys around the Sun, but the unexpected thing about this is that the energy levels it receives from Proxima Centuari are close to what our planet gets. This has the scientists convinced that liquid oceans could exist at its surface temperature, possibly as vast as those on Earth, and the presence of water could possibly mean life—at least life as we recognize it. You never know what could be out there after methane-eating bacteria were found right here on Earth. Saturn’s moon Titan is covered in lakes of methane and ethane, so you can see where this is going.

Whether or not Proxima b could be a hotbed of life most likely depends on whether an atmosphere exists. It would need an atmosphere that could hold its own against 400 times the X-rays that reach Earth. Our atmosphere absorbs X-rays, which makes the planet safer for life, though it can be a pain for X-ray observatories trying to detect signals from deep space. X-ray photons, or high-powered molecules of energy, can go no further after they smash into individual atoms in our atmosphere that absorb them. Any that do make it to Earth have to dodge as many atoms as they would if they were trying to pass through a 16-foot-thick wall of concrete. Some insist that even an atmosphere like Earth’s would not be a strong enough X-ray shield. Without a protective enough atmosphere, life would be extinguished. Just look at what happened to Mars.

“Is there an atmosphere that protects the planet from these deadly rays?” researcher Christophe Lovis who is responsible for ESPRESSO’s scientific performance and data processing, asked in a press release. “And if this atmosphere exists, does it contain the chemical elements that promote the development of life (oxygen, for example)? How long have these favorable conditions existed?”

Not that there’s any guarantee that creatures which didn’t originate on Earth breathe oxygen and absolutely need water, but the conditions on our planet are what we have to go off of. Lovis and the other scientists who collaborated to make ESPRESSO’s Proxima b observations happen believe that those answers will emerge in the future as instruments continue to level up. The upcoming RISTRETTO spectrometer is being designed specifically to zero in on Proxima b and detect the light it gives off. HIRES (High Resolution Spectrograph) is another super-hi-res instrument that will be able to study faint objects in space and find out what their atmospheres are made of—if they have atmospheres at all.

Either of these instruments could tell us whether Proxima b is actually habitable. HIRES is currently being developed for use with ESO’s Extremely Large Telescope, which, when completed, will be the largest optical/near-infrared telescope ever.

For now, scientists will just have to keep debating whether or not anything could live on Proxima b until there is proof for or against an atmosphere.

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P.E.I. fishermen surrounded by 'thousands' of jellyfish – CBC.ca

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Just outside the Tryon River on Prince Edward Island, Brian Campbell’s boat motor began to stall as it became surrounded by lion’s mane jellyfish. 

“I’ve never seen that many before,” said Campbell. “They would get caught up in that propeller. There’s quite a few of them — I want to say thousands and thousands.”

Lion’s mane jellyfish can grow to two metres in diameter with tentacles as long as 30 metres, roughly the same length as a blue whale. 

What’s more? They sting.

High concentration of lion’s mane

“Wouldn’t want to be swimming there that day, that’s for sure,” said Campbell, who has been a fisherman for 42 years. 

“It’s all right if you got one or two that sting you. But at that point right there, I think you could probably do some harm … if you get 30 or 40 on you.”

Last Tuesday, Campbell posted on Facebook warning people not to swim in the area. He later added a video of the encounter. 

[embedded content]

Oceanographer Nick Record says the species is common throughout Atlantic Canada and the Gulf of Maine, but this is the first he’s heard of such a large group.

“I’m pretty sure that’s the highest concentration of lion’s mane jellyfish that anyone has reported to me,” said Record, a senior research scientist at the Bigelow Laboratory for Ocean Sciences, a non-profit research institution in Maine. 

‘Just giants’

Record said he has noticed a new phenomenon of gigantic lion’s mane jellyfish washing up onshore.

“They’re usually about the size of a dinner plate or smaller,” he said. “The last 18 months or so there’s been a handful, maybe five to 10 instances, where they were like [one and a half to two metres] across — so just giants.”

Nick Record says he receives between 100 and 1,000 reports of jellyfish sightings each year. (Bigelow Laboratory for Ocean Sciences)

Record has been using citizen reports to track the creatures for about a decade. He said it’s hard to know whether or not  jellyfish are increasing based on the reports, because while more reported sightings could mean more jellyfish, it could also just mean more people are out on the water.

That being said, there are several factors that could impact the population including weather, currents and the food chain. 

“Partly it’s the biology. Jellyfish can reproduce really quickly when conditions are good,” said Record. “Partly it’s the ocean physics.”

‘I couldn’t believe how many there was’

“When I first saw it, I thought maybe somebody hit a seal up there just a little ways away,” said Chad Gallant, a lobster fisherman in North Rustico, P.E.I.

“There was a bunch of pink in the water. I thought it might’ve been blood.”

It wasn’t blood, it was jellyfish. 

Unlike other living organisms, jellyfish can survive and thrive in stressed environments with little oxygen and depleted ecosystems. (Chad Gallant)

These were moon jellyfish, a different species from those Campbell saw.

“We just stopped there,” said Gallant. “I couldn’t believe how many there was.”

Gallant also posted a video on Facebook. 

“It’s not too surprising to me to see a really high abundance of them,” said Record. ” But I’ve never seen a photo where they were that dense before.”

Moon jellyfish are seasonal and feed on zooplankton, according to Record. He said they “don’t generally sting,” but some people have sensitivities or allergic reactions to them. 

“I thought it was kinda cool,” laughed Gallant. “It don’t bother me from going swimming again.” 

Competing with fish for food

Record said there are both pros and cons to seeing groups this large. 

“Some people see jellyfish as a total nuisance and large jellyfish aggregations as an unequivocally bad thing,” he said. “Other people see jellyfish as these amazing, beautiful animals and just want to take photos of them all day.”

They can impact the ecosystem in many ways, too. On one hand, they’re prey for sea turtles. On the other, they compete with fish for food. 

There’s a scientific debate about whether jellyfish are increasing globally or not.— Nick Record, Bigelow Laboratory for Ocean Sciences

“People have tried to get fish stocks to rebound, but because the [jellyfish] are eating the same food that the fish would be eating, it makes it more difficult for fish stocks to come back,” said Record. 

But unlike other living organisms, the jellyfish can survive and thrive in stressed environments with little oxygen and depleted ecosystems. 

More data needed

“There’s a scientific debate about whether jellyfish are increasing globally or not,” said Record. “In order to answer the question about whether there’s a long-term trend, you need decades of data.

“We don’t really have that in Atlantic Canada.” 

According to Record, this citizen reporting program is “really the only long-term survey for jellyfish in our part of the world.” 

In order to track the sea animal, Record has to know where they are. And to know where they are, he needs people to report them. Record said people can send information regarding sightings to jellyfish@bigelow.org.

There’s little doubt the videos taken around P.E.I. show a significant number of jellyfish. However, whether this means their population is climbing, the response isn’t so clear. 

“We don’t know yet,” said Record. “It’ll take many years before we can answer that question.” 

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First ever glimpse of the core of a gas giant after one found orbiting distant star – Sky News

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Scientists have discovered the surviving core of a gas giant orbiting a distant star, offering the first ever glimpse of the interior of these mysterious planets.

The core is about the same size as Neptune, or around four times larger than Earth, although it isn’t clear what happened to the planet’s gaseous atmosphere.

According to researchers from the University of Warwick’s department of physics, the atmosphere could have been stripped away or it may have failed to form early on in the planet’s life.

Image:
The planet could have once been similar to Jupiter. Pic: NASA

The planet core was found in a survey of stars by NASA’s Transiting Exoplanet Survey Satellite (TESS) and offers a unique opportunity to learn about the composition of gas giants.

Planets such as Jupiter, Saturn and Neptune are believed to have a rocky core deep beneath the bulk of their mass which is made up of gases.

Although the new core, named TOI 849 b, is around the same size as Neptune, it is believed to have three times the mass, with the material making it being squashed much more densely.

Dr David Armstrong, lead author on the paper, said: “While this is an unusually massive planet, it’s a long way from the most massive we know.

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“But it is the most massive we know for its size, and extremely dense for something the size of Neptune, which tells us this planet has a very unusual history,” he added.

“TOI 849 b is the most massive terrestrial planet – [a planet] that has an earth-like density – discovered.

“We would expect a planet this massive to have accreted large quantities of hydrogen and helium when it formed, growing into something similar to Jupiter. The fact that we don’t see those gases lets us know this is an exposed planetary core.”

The Transiting Exoplanet Survey Satellite (TESS). Pic: NASA
Image:
It was discovered by the Transiting Exoplanet Survey Satellite (TESS). Pic: NASA

Dr Armstrong said this was the first time scientists have discovered an intact exposed core of a gas giant orbiting around a star.

There are two theories as to why the planet’s core has been exposed.

The first is that it was once similar to Jupiter but lost its outer gas, potentially through tidal disruption – when it was ripped apart from orbiting too close to its star – or in a collision with another planet.

Alternatively, it might be a failed gas giant, which never formed an atmosphere – for instance if there was a gap in the disc of dust the planet formed from, or if the disc ran out of material.

Dr Armstrong added: “It’s a first, telling us that planets like this exist and can be found. We have the opportunity to look at the core of a planet in a way that we can’t do in our own solar system.

“There are still big open questions about the nature of Jupiter’s core, for example, so strange and unusual exoplanets like this give us a window into planet formation that we have no other way to explore.

“Although we don’t have any information on its chemical composition yet, we can follow it up with other telescopes.

“Because TOI 849 b is so close to the star, any remaining atmosphere around the planet has to be constantly replenished from the core. So if we can measure that atmosphere then we can get an insight into the composition of the core itself.”

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A buck moon lunar eclipse will be visible on the Fourth of July – Lonely Planet Travel News

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The Fourth of July is always a big celebratory occasion in the US, and while it may be a bit more subdued this year because of the COVID-19 pandemic, it coincides with a special lunar event.

A penumbral lunar eclipse will be visible on July 4 and 5 in many parts of the world, providing skies are clear. This is where the full moon in July will sweep to the north of the Earth’s dark shadow – or penumbra – causing a partial eclipse of the moon. It’s a more subtle phenomenon than a total eclipse, and it will turn the moon a shade darker as it is eclipsed by the Earth’s penumbral shadow.

Where to travel based on your star sign

People in the northwestern areas of the US and Canada will only be able to see the eclipse at moonrise, and those in much of Africa and parts of western Europe will see it at moonset. Alas, it will not be visible in Asia, eastern Europe, the northernmost areas of North America and northeastern Africa.

Full moons take place every 29.5 days © Gary Hershorn/Getty Images

A full moon happens every 29.5 days, and the one in July is called the ‘buck moon.’ This is because Native American tribes originally tracked the changing seasons by the lunar months rather than the solar calendar and gave them names appropriate to the time of year. July’s full moon is called the buck moon as it coincides with when male deer, or bucks, shed their antlers every year, and new ones emerge. It is also sometimes called the thunder moon, hay moon and wort moon.

The eclipse will begin on July 4 at 23.07 EDT and last until 1.52 EDT on July 5.

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