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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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B.C.'s "living dinosaurs" threatened by ocean warming and acidification – Straight.com

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The world’s warming oceans and the ongoing acidification of seawater are having a serious effect on B.C.’s rare glass sponges and their associated reefs, according to a study conducted by UBC researchers.

The sponge reefs—constructed by living glass sponges growing on the skeletons of previous generations—can grow to the height of a six-storey building and were thought to have become extinct worldwide about 40 million years ago, until the discovery of  massive reefs 200 metres deep in Hecate Strait in northern B.C. in 1987 (although they had been observed as unexplained “mounds” on the floors of Queen Charlotte Sound and Hecate Strait during sonar surveys a few years previous).

At the time, the reefs were described by astonished scientists as “living dinosaurs”. German paleontologist Manfred Krautter was quoted as saying their discovery in B.C. waters “electrified” him and was “like discovering a herd of dinosaurs on land”, and the prehistoric constructs are often referred to as “Jurassic Park submerged”.

Subsequent dives by scientists in submersibles determined that they were up to 6,000 years old and covered a surface area of up to 700 square kilometres. It is theorized that the sponges, which are living marine animals, started building reefs there after B.C.’s most recent glaciation period scraped the ocean bottom clean more than 9,000 years ago.

Since the first discoveries, another 19 glass-sponge reefs have been found in the Strait of Georgia, part of what is often called the Salish Sea. An American geologist found other, specialized, reefs off the coast of Washington state in 2007.

The sponges use dissolved silica—glass, essentially—to build skeletons constructed of needlelike so-called spicules. Although glass sponges are common around the world, only in very rare cases do they form reefs, building new structures on top of the skeletons of dead sponges. The relatively accessible reefs found in Howe Sound are unique in the world for their shallow depth of less than 40 metres.

The UBC paper—published on May 18 in Scientific Reports, an open-access, peer-reviewed journal—detailed the results of an experiment initiated by Angela Stevenson, a postdoctoral fellow at UBC’s zoology department who is the study’s lead researcher. Stevenson was aided by scientists from Fisheries and Oceans Canada’s Pacific Biological Station in Nanaimo, Vancouver’s Ocean Wise Research Institute, and UBC’s department of botany.

Stevenson brought some examples of Aphrocallistes vastus—called the cloud sponge and one of three species of reef-building glass sponges found in B.C. waters—from Howe Sound to a UBC lab. Water temperature and acidity were then manipulated for a four-month study, resulting in the first successful long-term lab experiment involving living glass sponges.

““Their sheer size and tremendous filtration capacity put them at the heart of a lush and productive underwater system, so we wanted to examine how climate change might impact their survival,” Stevenson said in a June 1 UBC news release.

The researchers were monitoring the sponges’ durability, pumping ability, and skeletal strength. The results showed that the sponges experienced up to a 25 percent loss in tissue and a 50-percent reduction in pumpong capacity. Their bodies also became more elastic and lost about half their strength.

“Most worryingly, pumping began to slow within two weeks of exposure to elevated temperatures,” Stevenson noted.

Glass-sponge reefs are home to many marine creatures in B.C., including fish and giant Pacific octopuses.
Diane Reid/Ocen Wise

Glass sponges survive by pumping enormous volumes of water through their systems, filtering out the bacteria and plankton that they eat and purifying the surrounding seawater. It is estimated that the 19 reefs that are known to be in the Salish Sea can filter up to 100 billion litres of seawater every day, removing about 80 percent of the particles and microbes therein.

The Canadian Parks and Wilderness Society’s (CPAWS) B.C chapter, which advocates to protect glass-sponge reefs, says that 95 percent of seawater bacteria are filtered out by glass sponges and that a small reef of the sponges will filter and clean a volume of water every 60 seconds that would fill an Olympic-sized swimming pool.

Diver Glen Dennison above a Howe Sound glass-sponge reef.
Adam Taylor/Marine Life Sanctuaries Society

The reefs are protected by various conservation efforts in B.C’s deep northern waters and shallower Salish Sea depths, including federal marine protected areas in Hecate Strait and Queen Charlotte Sound and smaller buffer zones in Howe Sound and the Strait of Georgia. CPAWS says that research shows both measuers require expansion to fully protect the delicate structures from potential fishing and resource-exploration damage.

Borttom fishing, especially trawling, can devastate glass-sponge reefs, and suspended sediment can choke the sponges’ feeding filters and even kill them. Crab and prawn traps can damage or crush the sponge skeletons.

Jeff Marliave, an Ocean Wise senior researcher and paper coauthor, said in the release that more study is needed to understand how climate change might affect the reefs. “In Howe Sound, we want to figure out a way to track changes in sponge growth, size and area and area in the field so we can better understand potential climate implications at a larger scale. We also want to understand the microbial food webs that support sponges and how they might be influenced by climate cycles.”

Stevenson had a cautionary thought about what is required to guarantee the future safety of the reefs, whaich have been described as “international treasures”.

“When most people think about reefs, they think of tropical shallow-water reefs like the beautiful Great Barrier Reef in Australia,” Stevenson said. “But we have these incredible deep-water reefs in our own backyard in Canada. If we don’t do our best to stand up for them, it will be like discovering a herd of dinosaurs and then immediately dropping dynamite on them.”

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What a dinosaur's last supper reveals about life in the Cretaceous period – CBC.ca

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A beautifully preserved armoured dinosaur found in an Alberta oilsands mine died on a full stomach. The “extraordinarily rare” preservation of its last meal offers new clues and surprises about how the dinosaur lived during its last days.

The 5.5-metre-long, 1,300 kilogram spiky, plant-eating nodosaur, similar to an ankylosaurus but without a tail club, is the only known one of its species, Borealopelta markmitchelli. (Its name means “shield of the north” and honours Mark Mitchell, the technician who spent 7,000 carefully extracting the fossil from the surrounding rock). 

Victoria Arbour, an evolutionary paleontologist at the Royal BC Museum, describes how some armoured dinosaurs likely used their horns, spines and armour for fighting each other, not just for protection. 1:34

The nodosaur lived 110 million years ago during the early Cretaceous, in a lush forest of conifers, ferns and palm-like plants called cycads, near the coast of what was then an inland sea. At the time, the climate was warmer, similar to that of South Carolina, said Caleb Brown, a paleontologist at the Royal Tyrrell Museum of Paleontology in Alberta and lead author of the new study. It was published this week in the journal Royal Society Open Science.

The fossil was discovered by accident in 2011 by Shawn Funk, a shovel operator at the Suncor Millennium Mine near Fort McMurray. Paleontologists from the Royal Tyrrell were called to have a look and realized at once that it was no ordinary fossil.

While most fossils include only bones, this one included skin. It was so well-preserved that it has been described as “mummified.”

Meet one of the world’s best-preserved dinosaurs ever. Borealopelta fossilized so perfectly that we can see every inch of its armour and skin in 3D, 110 million years after its death. 0:58

In the dinosaur’s belly, “there were these massive concentrations of what looked like rocks,” Brown said.

Those were in a mass about the size of a soccer ball, and it appears they were gastroliths — rocks that some plant-eating dinosaurs use to grind up their food in their stomachs, as modern birds do, instead of using their teeth.

Sure enough, when chunks of the mass were encased in resin, sliced and examined under the microscope, the researcher could see well-preserved twigs, leaves, mosses, pollen and spores.

To get some help at identifying the plant material, the dinosaur researchers turned to paleobotanists, including University of Brandon researcher David Greenwood and his team, along with their retired Royal Tyrrell colleague Dennis Braman.

Inside the nodosaur’s belly was a mass about the size of a soccer ball that contained rocks. The rocks are called gastroliths and are used to grind up the animal’s food within its stomach. (Royal Tyrrell Museum)

Ferns and charcoal

They discovered that the dinosaur was a bit of a picky eater. While it lumbered through a landscape that was lush with conifers, horsetails and cycads, there weren’t a lot of those in its stomach.

“It’s almost all ferns,” Brown said, noting that ferns aren’t actually very nutritious. “It wasn’t just hoovering up everything on the landscape.”

But to him, the biggest surprise was that the stomach also contained a significant amount of wood, mostly charcoal, suggesting it was feeding in an area that had recently been ravaged by wildfires.

“And that’s a really cool result,” Brown said. “Because if you look at large mammals that are herbivores today, they often seek out areas that are recovering from forest fires.”

That’s because the new growth tends to be lush, more nutritious than older plants, and low to the ground where it’s easily accessible.

Microscope images show some of the plant material found inside the stomach, including a club moss spore sac (a), fern spore sacs (b-d), a charcoal fragment (e), parts of plant stems and leaves (f-l) and a cross section of a twig, showing its annual rings (m). (Brown et al/Royal Tyrrell Museum)

Forensic paleobotany

By looking at the types of spores and the fact that the twigs appeared to be in the middle of their growing season, the researchers figured out that the animal died during the wet season, which was late spring or early summer.

In Dinosaur Cold Case, a recent documentary about the fossil on CBC’s Nature of Things, Greenwood said extreme storms and flash floods would have been a problem at that time of year on the coastal plain where the dinosaur and suggested that being swept away by rushing water may have been what caused its death.

These are some plant fossils from Alberta from about the time that Borealopelta lived, including ferns, a gingko (d), horsetails (i) and a conifer cone (j). (Brown et al/Royal Tyrrell Museum)

The discoveries about the nodosaur’s last meal are significant because to date, Brown said, “we know almost nothing about what herbivorous dinosaurs eat.”

Only guesses can be made based on what plants lived nearby and the dinosaur’s teeth. There are also clues in fossil dinosaur feces, but the plant material in those are often digested beyond recognition and it’s difficult to know which dinosaur they came from.

Part of the problem is that finding preserved stomach contents from a dinosaur is “extraordinarily rare,” Jim Basinger of the University of Saskatchewan, a co-author of the study, said in a statement. 

Nine cases of possible dinosaur stomachs of plant-eating dinosaurs have been found, the researchers note, but most have turned out to just be plant material found nearby rather than actual stomachs. In this case, the dinosaur was washed far out to sea, without any plants from the landscape it lived in, before it was fossilized.

“So in this case we have what I would say is by far the best evidence that these are stomach contents,” Brown said.

That said, he notes that it may not necessarily be representative of what this species normally ate, as an animal’s diet can vary depending on its age, its health, and the seasonal availability of different foods.

Still, he said it’s useful to be able to compare it to what scientists think plant-eating dinosaurs were eating at that time and raises new questions to investigate, such as: How much of this food a dinosaur this size would have needed to eat to sustain itself? And how did it digest it?

 “I think give us a benchmark for figuring out how this animal may have lived.”

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‘Strawberry Moon’ to rise with a special eclipse for some skywatchers – Globalnews.ca

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The full moon on Friday, June 5 might look a little different in some parts of the world, where the so-called “Strawberry Moon” will fall partially under the Earth’s shadow.

The phenomenon, known as a penumbral lunar eclipse, occurs when the Earth comes between the sun and the moon, thereby casting a faint shadow on the moon. This penumbral lunar eclipse will make the full moon look slightly darker on part of its surface, although only some portions of the world will see it.

The penumbral lunar eclipse will only be visible from parts of Australia, Asia, Africa, Europe and South America, according to NASA’s charts.


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In other words, North Americans will need to watch a livestream on the internet to catch a glimpse of the event, which starts at 3 p.m. EDT. Nevertheless, the so-called “Strawberry Moon” will be visible to everyone.

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That name comes from the time of year and not the expected colour of the moon. There are farm-related nicknames for the first full moon of every month, and the strawberry nickname originated from the Algonquin First Nation, according to the Old Farmer’s Almanac. The first full moon of June often coincided with the harvest season for wild strawberries in North America, the Almanac says.


The Strawberry Moon is practically full over the horizon as a lady poses for a photo in Malaga, Spain, on June 4, 2020.


Jesus Merida/SOPA Images/LightRocket via Getty Images

Although skywatchers in Canada and the U.S. will miss out on this penumbral lunar eclipse, they’ll only have to wait a month to catch the next one. Another penumbral lunar eclipse is slated to happen on July 5, and that one should be visible from North America. The darkest penumbral lunar eclipse of the year is expected on Nov. 30.

A penumbral lunar eclipse also happened on Jan. 10, coinciding with that month’s “Wolf Moon.”

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Timelapse captures moment sky darkens for total solar eclipse


Timelapse captures moment sky darkens for total solar eclipse

Not to throw shade at the penumbral lunar eclipses, but they’ll likely pale in comparison to the annular solar eclipse predicted for June 21. That’s when the moon will pass between the Earth and the sun, making the sun look like a ring of fire for viewers in parts of Africa, China, northern India and Pakistan, according to TimeandDate.com.

Again, it won’t be visible from North America — but you’ll still be able to watch the whole thing online without risking eye damage from staring at the sun.

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© 2020 Global News, a division of Corus Entertainment Inc.

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