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The last time the sun was this quiet, Earth experienced an ice age – 9News

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At the centre of our solar system, the sun is a constant force keeping planets in orbit, providing Earth with just the right amount of light and warmth for life and even governing our daily schedules.

While we’re used to the sun rising and setting each day, the sun itself is incredibly dynamic and just like us, it goes through phases and changes.

Over time, those changes in our star have become more predictable. Currently, it’s going through a less active phase, called a solar minimum.

The sun is experiencing a less active phase called ‘solar minimum,’ but it won’t cause an Ice Age. (CNN)

The sun experiences regular 11-year intervals including energetic peaks of activity, followed by low points.

During the peak, the sun showcases more sunspots and solar flares.

In a solar minimum, the sun is much quieter, meaning less sunspots and energy.

Scientists at NASA say we’re currently in a “Grand Solar Minimum.”


Climate Change and its impact on the sun

The last time this occurred was between 1650 and 1715, during what’s known as the Little Ice Age in Earth’s Northern Hemisphere, “when combination of cooling from volcanic aerosols and low solar activity produced lower surface temperatures,” according to NASA’s Global Climate Change blog.

But this solar minimum won’t spark another ice age, scientists say, and that’s likely due to climate change.

“The warming caused by the greenhouse gas emissions from the human burning of fossil fuels is six times greater than the possible decades-long cooling from a prolonged Grand Solar Minimum,” NASA scientists wrote.

“Even if a Grand Solar Minimum were to last a century, global temperatures would continue to warm.

“Because more factors than just variations in the Sun’s output change global temperatures on Earth, the most dominant of those today being the warming coming from human-induced greenhouse gas emissions.”

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NASA scientists have confirmed that the solar minimum will not lead to an Ice Age, due to climate change. (AAP)

Scientists have known this solar minimum was coming because it’s a regular aspect of the sun’s cycle. Sunspots were peaking in 2014, with low points beginning in 2019, according to NASA.

The sun is also responsible for what’s known as space weather, sending particles and cosmic rays streaming across our solar system. The sun’s strongly magnetised sunspots release solar flares, which can send X-rays and ultraviolet radiation hurtling toward Earth.

Even when the sun is quiet during the solar minimum, it can be active in other ways, like coronal holes that open in the sun’s atmosphere and send out blazing streams of energised particles flying through the solar system on rapid solar wind.

Much like solar flares, these streams of particles during a solar minimum can disrupt the communication and GPS we rely on from satellites.

“We see these holes throughout the solar cycle, but during solar minimum, they can last for a long time — six months or more,” Dean Pesnell said, project scientist of the Solar Dynamics Observatory at NASA’s Goddard Space Flight Centre.

More highly energetic particles called galactic cosmic rays can reach Earth, specifically its upper atmosphere, during a solar minimum. These are created by explosions across our Milky Way galaxy, like supernovae.

“During solar minimum, the sun’s magnetic field weakens and provides less shielding from these cosmic rays,” Mr Pesnell said.

“This can pose an increased threat to astronauts traveling through space.”

This solar minimum ends solar cycle 24. Early predictions estimated the peak of solar cycle 25 will occur in July 2025, according to the National Oceanic and Atmospheric Administration.

The solar cycle forecast is based on a NOAA and NASA co-chaired international panel. They agree that solar cycle 25 will be similar to cycle 24.

“The Sun goes through regular cycles of high and low activity. This cycle affects the frequency of space weather events, but it doesn’t have a major effect on Earth’s climate — even an extended minimum wouldn’t have a significant effect on global temperature,” NASA said via Twitter.


Studying the sun

In August 2018, NASA launched the Parker Solar Probe to draw closer to the sun than any satellite before.

It’s a unique opportunity to study “the star in our backyard,” according to NASA Heliophysics Division Director Nicola Fox.

The probe was designed to help answer fundamental questions about the solar wind that streams out from the sun, flinging energetic particles across the solar system.

Its instruments may also provide insight about why the sun’s corona, the outer atmosphere of the star, is so much hotter than the actual surface.

The corona is one million kelvins, while the surface is around 6,000 kelvins.

Understanding the solar wind and the blazing heat of the corona are key – they both play a role in space weather and solar storms and understanding the solar wind could enable better prediction of space weather.

Solar wind and the corona’s temperature also impact ejections of mass from the corona, which could impact the global power grid and telecommunications on Earth, as well as our astronauts on the International Space Station. The energised and accelerated particles streaming away from the sun in the solar wind are also responsible for the northern and southern lights we see on Earth.

Some of the first results from the probe’s early passes around the sun have already proved intriguing.

During its first close encounter with the sun, the Parker Solar Probe essentially kept itself suspended over a hole in the corona for a week, watching solar wind particles streaming along the line of the sun’s magnetic field and out into space.

“It’s amazing, even at solar minimum conditions, the sun produces many more tiny energetic particle events than we ever thought,” David McComas said, principal investigator for the Integrated Science Investigation of the Sun suite at Princeton University in New Jersey.

“These measurements will help us unravel the sources, acceleration and transport of solar energetic particles and ultimately better protect satellites and astronauts in the future.”

Over the course of the probe’s seven-year mission, its orbit will shrink, bringing it closer and closer to the sun over the course of 21 approaches.

The probe will orbit within 3.9 million miles of the sun’s surface in 2024, closer to the star than Mercury.

Although that sounds far, researchers equate this to the probe sitting on the four-yard line of a football field and the sun being the end zone.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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