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Stunning New Videos Show Our Final Glimpses Of The Webb Telescope—And There’s A Lot More Drama To Come – Forbes

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It may not be as dramatic as the video showing the dramatic landing on Mars of NASA’s Perseverance rover, but the departure of the James Webb Space Telescope (JWST or “Webb”) from Earth orbit just got the HD treatment.

The video—which was shot by a camera from Irish company Réaltra Space Systems Engineering onboard the upper stage of the Ariane-5 rocket that took Webb into orbit—has now been made available.

Webb separation from the Ariane 5 occurred at 12:47:14 GMT on Christmas Day with its solar array deployed 69 seconds later, capturing sunlight to power the observatory.

Our last view of Webb is also available to download on the European Space Agency website. It’s also on YouTube:

A slew of amateur astronomer also caught glimpses of Webb as it flew across the constellation of Orion.

This video, shot in the Czech Republic by amateur astronomer Zdenek Bardon, shows Webb in the Orion constellation while it was 350,000 miles distant.

The sequence was shot prior to its sunshield folding out—an action that will increase its surface area and make it glint far brighter—Webb appears as a tiny dot. It’s about the same brightness as a very dim star and can’t be seen by the naked eye.

Come early January 2022—after the unfolding of its sunshields—it’s hoped that Webb will be a little brighter (albeit further away). Bright enough, hopefully, for it to show up easily in observations from Earth.

The Virtual Telescope Project—which published this image of Webb—is planning a live feed during which in will show in real time Webb being observed from ground-based robotic telescopes.

Its live feed is scheduled for January 7, 2022, starting at 21:30 UTC.

As it travels nearly a million miles to its destination, the second Lagrange point (L2), Webb will undergo a complex unfolding sequence. There are 300 single-point failure items, 50 parts and 178 release mechanisms.

The sunshield has five super-thin layers, dozens of hinges, motors, gears, springs and 1,312 ft. of cables. The 107 myriad release mechanisms need to fire on cue to erase the five layers. NASA is providing regular updates on its Webb telescope blog, Where is Webb? interactive tracker and a Deployments Explorer.

After it’s arrived at its observing location, which it will do by the end of January, the instruments will be gradually switched on and tested. After half a year of commissioning in space, Webb will start its routine science observations and deliver its first images.

Wishing you clear skies and wide eyes.

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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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