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Discovering the universe's origins through the James Webb Space Telescope – North Country Public Radio

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Todd Moe, Monica Sandreczki and Aileen O’DonoghueFollow the journey of the James Webb Space Telescope

Grab your binoculars and step outside on these clear winter nights. You’ll see Mercury rise up towards Saturn, with Jupiter nearby, before Saturn sets in late January and Jupiter sets in late February. Image courtesy of Aileen O’Donoghue.

This month during our astronomy chat with Aileen O’Donoghue, physics professor at St. Lawrence University, it’s all about the James Webb Space Telescope, which has finished unfolding it’s large 18 hexagonal mirrors after launching in late December. 

AILEEN O’DONOGHUE: It’s been huge that they got the deployment complete in all its complexity. I mean, these five sheets of gossamer thin, almost Mylar that create the sunshield. They’re the size of a tennis court.

MONICA SANDRECZKI: Wow.

O’DONOGHUE: And they deployed these things, and that all of these steps went well! I was watching on NASA TV every morning as they were going through this. It’s just amazing. It is going to teach us so much about different things in the universe. We’ve been waiting for it since the 80s and it’s been supposed to launch for like 10 years. The astronomy community was holding its breath (when it launched) on Christmas Eve.

SANDRECZKI: Yes, I was reading that some NASA scientists felt like this was like one of the biggest accomplishments was even just getting those mirrors opened up.

O’DONOGHUE: Yes to unfold all that stuff and that it worked! So the next step – and that’s going to take a few months – is getting those mirrors aligned. There are 18 independent hexagonal mirrors, they can move on, like one 10,000th of a human hair. They can move them in three dimensions back and forth, up and down, side to side, and then they tilt as well, and then move them around to create a really sharp image. It’s just gonna be magnificent. And, since it’s a team, we hopefully won’t run into a problem like Hubble.

SANDRECZKI: What’s its path going to be? Because it’s headed towards a final, sort of, resting place. Is that right?

O’DONOGHUE: Right! It’s going to the second Lagrange point, so what this is, Earth and the Sun, Earth orbiting the sun; they both have a gravitational pull and there are some points where those gravitational forces and the rotational forces give you a balance point. There’s one directly between Earth and Sun. That makes sense. Oh, yeah, there’s place where you fold equally, but there’s one on the far side of Earth as well. So, that’s where James Webb is going.

The James Webb Telescope as it heads into deep space. Credit: Arianespace, ESA, NASA, CSA, CNES

The James Webb Telescope as it heads into deep space. Credit: Arianespace, ESA, NASA, CSA, CNES

O’DONOGHUE: So it’s going to be beyond Earth by about 100 million miles. And… it’s not that far, I’m losing my mind. I’m just suddenly doubting my numbers that I looked up yesterday. Oh, it is!

It is 100 million miles, so it’s well beyond the orbit of the moon. It’ll sit out there; it will orbit the sun at the same rate as the Earth; it’ll just sit there still in our sky, so if you can figure out the point, directly away from the Sun at midnight, you can look out, not straight overhead, but out at an angle, you’ll be able to see the point where the James Webb Telescope is sitting in our city, midnight sky; it’s going to orbit this kind of equilibrium point.

The reason that we want it that far, is because it observes in the infrared; it observes in what we detect as heat…

SANDRECZKI: Which is different than the Hubble…

O’DONOGHUE: Right. It does see some visible wavelengths; it sees into about a gold color, a little redder than the gold of the mirrors, is as far into the visible it sees, but then it sees to much longer wavelengths, like the night vision glasses that soldiers and firemen wear.

The reason that we need it to do this is because we want to look at the early universe.

The universe is expanding, so that means that an object that emits a visible wavelength emitted a visible wavelength as it has crossed the universe, has gotten stretched so that it’s now in the infrared. 

With James Webb, the most exciting stuff – well, for me – is that we can look at objects very, very early in the universe, objects that were being formed 100 million years after the beginning of the universe.

These galaxies that we see as red smudges on the Hubble Space Telescope images, well, James Webb is about three times the size and diameter. So nine times the collecting area of the Hubble Space Telescope. It’s gonna be able to see finer detail and see fainter objects.

TODD MOE: Are you saying, Aileen, that we’re in for a treat in terms of amazing photographs?

O’DONOGHUE: Oh, absolutely, absolutely. It’s going to be probably not as big a leap as Hubble was because we lost the fuzziness of the atmosphere, but almost as big a leap in terms of what we’re going to be able to see. Plus, that it can see through dust that blocks visible light, dust does emit, but it emits at different wavelengths, and the wavelengths coming through it, we can see. So it’s going to also look at the disks around forming stars to see if we can see forming planets. It’s going to look into these dark clouds of gas and dust, like the Orion Nebula and see where baby stars are forming. And so it’s even going to look at Mars and look for molecules of water, and see where there’s water sitting around because some of the infrared can pass through some of the surface materials.

It’s gonna look at Ganymede and see if there’s a subsurface ocean; look at Europa, these nearby worlds, it’s just, it’s going to show us things that we haven’t been able to see.

SANDRECZKI: Those moons of Saturn and Jupiter are amazing!

O’DONOGHUE: Enceladus. Yeah, that has these geysers going off. This little world that’s 100 billion miles from the sun. And it has geysers. So it’s just very exciting. And the fact that it all deployed, and it all worked is just astounding.

MOE: Let’s hear it for origami.

O’DONOGHUE: And you can watch it. I just Googled James Webb Space Telescope, NASA. And they have a you can get to the NASA webpage. And they have a “Where his Webb?” And it is just amazing and looking at that right now. The Webb is 722,000 miles from Earth.

It’s going to see these things we haven’t been able to see: the disks around forming stars to see if we can see forming planets. It’s going to look into these dark clouds of gas and dust, like the Orion Nebula and see where baby stars are forming.

It’s even going to look at Mars and look for molecules of water! 

MOE: Well, we got about a minute and a half here, Aileen. So let’s talk about things you can see without a telescope in the night and morning skies.

O’DONOGHUE: Oh, yeah, and it’s gonna be clear tonight, which is why it’s going to be very cold. So get out your binoculars right after sunset and look to the western sky. You ought to be able to see Jupiter; below Jupiter and a little bit to the right about two fists worth you should be able to pick out Saturn and then Mercury is a half of fist away from Saturn and they’re going to be fairly close. You ought to be able to see those two within the same field of view of binoculars. So I would find Jupiter with your eye and then see if you can find Satur. You might use binoculars just to pick it out because it’s still going to be kind of bright because they set, you know, like by 6:30 or something. But get out there six o’clock, or even 5:30. Go out and see if you can look for these. Those are exciting to see.

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Mars Was Likely A Cold, Wet World 3 Billion Years Ago – IFLScience

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Mars is puzzling. From rover and satellite observations we know that it once had plenty of water on its surface, which usually suggests warm and wet conditions. On the other hand, evidence suggests the planet was always pretty chilly, even in the distant past, but it’s not a cold, dry desert either. These two ideas are often at odds, but new research suggests that they could both be true: ancient Mars was likely a frigid world both cold and wet.

Researchers set out to create a model that can explain the perplexing features witnessed on the Red Planet. If the planet wasn’t warm and wet or cold and dry could there be a third option? Publishing their findings in Proceedings of the National Academy of Sciences, they believe that their cold and wet scenario can explain the existence of a vast liquid ocean in the Northern Hemisphere of Mars, extending to its polar region.

However, the model needed to explain both the presence of a liquid ocean and ice-capped regions, like the presence of glacial valleys and ice sheets in the southern highlands.

Planetary scientists studying Mars have found evidence of ancient tsunamis that rocked the Red Planet. If the ocean was frozen due to a very cold climate, these tsunamis would not have happened. But a milder climate would have meant transferring water from the ocean to the land through precipitation. Cold and wet conditions, however, could have existed.

The team used an advanced general circulation model to work out the necessary parameters for this world. They calculated it was possible for an ocean to be stable even if the mean temperature of Mars was below 0°C (32°F), the freezing point of water, 3 billion years ago. They envisioned ice-covered plateaus in the south with glaciers flowing across the plains and returning to the ocean. Rainfall would have been moderate around the shoreline. In this scenario, the ocean surface could be up to 4.5°C (40°F); not tropical but enough for water to stay liquid.

The key to these conditions is all in the air. The atmosphere of Mars today is about 1 percent in density compared to Earth’s own. But, if in the past it was roughly the same and was made of about 10 percent hydrogen and the rest carbon dioxide, this scenario would actually work. Previous analyses have found strong evidence for a thicker atmosphere before it was ripped from the planet by the steady stream of particles from the Sun.

The model is certainly compelling in explaining the peculiarities of Mars, but of course, much more evidence is needed to understand what the Red Planet was really like billions of years ago.

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Explainer-Scientists struggle to monitor Tonga volcano after massive eruption

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Scientists are struggling to monitor an active volcano that erupted off the South Pacific island of Tonga at the weekend, after the explosion destroyed its sea-level crater and drowned its mass, obscuring it from satellites.

The eruption of Hunga-Tonga-Hunga-Ha’apai volcano, which sits on the seismically active Pacific Ring of Fire, sent tsunami waves across the Pacific Ocean and was heard some 2,300 kms (1,430 miles) away in New Zealand.

“The concern at the moment is how little information we have and that’s scary,” said Janine Krippner, a New Zealand-based volcanologist with the Smithsonian Global Volcanism Program.

“When the vent is below water, nothing can tell us what will happen next.”

Krippner said on-site instruments were likely destroyed in the eruption and the volcanology community was pooling together the best available data and expertise to review the explosion and predict anticipated future activity.

Saturday’s eruption was so powerful that space satellites captured not only huge clouds of ash but also an atmospheric shockwave that radiated out from the volcano at close to the speed of sound.

Photographs and videos showed grey ash clouds billowing over the South Pacific and metre-high waves surging onto the coast of Tonga.

There are no official reports of injuries or deaths in Tonga https://www.reuters.com/business/environment/impact-assessment-aid-efforts-underway-world-responds-tonga-tsunami-2022-01-16 yet but internet and telephone communications are extremely limited and outlying coastal areas remain cut off.

Experts said the volcano, which last erupted in 2014, had been puffing away for about a month before rising magma, superheated to around 1,000 degrees Celsius, met with 20-degree seawater on Saturday, causing an instantaneous and massive explosion.

The unusual “astounding” speed and force of the eruption indicated a greater force at play than simply magma meeting water, scientists said.

As the superheated magma rose quickly and met the cool seawater, so did a huge volume of volcanic gases, intensifying the explosion, said Raymond Cas, a professor of volcanology at Australia’s Monash University.

Some volcanologists are likening the eruption to the 1991 Pinatubo eruption in the Philippines, the second-largest volcanic eruption of the 20th century, which killed around 800 people.

The Tonga Geological Services agency, which was monitoring the volcano, was unreachable on Monday. Most communications to Tonga have been cut after the main undersea communications cable lost power.

LIGHTNING STRIKES

American meteorologist, Chris Vagasky, studied lightning around the volcano and found it increasing to about 30,000 strikes in the days leading up to the eruption. On the day of the eruption, he detected 400,000 lightning events in just three hours, which comes down to 100 lightning events per second.

That compared with 8,000 strikes per hour during the Anak Krakatau eruption in 2018, caused part of the crater to collapse into the Sunda Strait and send a tsunami crashing into western Java, which killed hundreds of people.

Cas said it is difficult to predict follow-up activity and that the volcano’s vents could continue to release gases and other material for weeks or months.

“It wouldn’t be unusual to get a few more eruptions, though maybe not as big as Saturday,” he said. “Once the volcano is de-gassed, it will settle down.”

 

(Reporting by Kanupriya Kapoor; Editing by Jane Wardell and Michael Perry)

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Astronauts at Risk of 'Space Anemia' | Health | thesuburban.com – The Suburban Newspaper

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MONDAY, Jan. 17, 2022 (HealthDay News) — Astronauts can develop a condition called space anemia because their bodies destroy more red blood cells than normal when in space, a groundbreaking study shows.

Assessments of 14 astronauts over six months between space missions found that 54% more blood cells were destroyed while they were in space than when they were on Earth, according to findings published Jan. 14 in Nature Medicine.

“Space anemia has consistently been reported when astronauts returned to Earth since the first space missions, but we didn’t know why,” said lead author Dr. Guy Trudel of the Ottawa Hospital Research Institute in Canada. “Our study shows that upon arriving in space, more red blood cells are destroyed, and this continues for the entire duration of the astronauts’ mission.”

Before this study, it was believed that space anemia was due to fluid shifting into an astronaut’s upper body upon arrival in space.

Astronauts lose 10% of the liquid in their blood vessels this way. It was thought that their bodies rapidly destroyed 10% of their red blood cells to restore the balance, and that red blood cell control returned to normal after 10 days in space.

But this study found that red blood cell destruction is a primary effect of being in space, not just the result of fluid shifts.

On Earth, our bodies create and destroy 2 million red blood cells every second. But the astronauts in this study — both male and female — destroyed 3 million every second while in space.

Five of 13 astronauts in the study were clinically anemic when they returned to Earth. One of the 14 did not have blood drawn on landing.

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The researchers also found that space anemia is reversible, with red blood cells levels progressively returning to normal three to four months after astronauts returned from space.

“Thankfully, having fewer red blood cells in space isn’t a problem when your body is weightless,” Trudel said in a hospital news release. “But when landing on Earth and potentially on other planets or moons, anemia affecting your energy, endurance and strength can threaten mission objectives. The effects of anemia are only felt once you land, and must deal with gravity again.”

The findings could be prove useful for patients who develop anemia after long illnesses that require bed rest. Bed rest has been shown to cause anemia, but how it does so is unknown.

The mechanism may be like what occurs in space anemia, according to Trudel, who plans to investigate this theory in future research.

More information

The American Academy of Family Physicians has more on anemia.

SOURCE: The Ottawa Hospital, news release, Jan. 14, 2022

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