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Euclid mission sets out in search of clues to universe’s biggest mystery – the nature of dark energy

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Scientists look over the Euclid space telescope in Cannes, France, on Feb. 21.VALERY HACHE

A mission to illuminate one of the universe’s darkest secrets is under way after a successful launch on Saturday at Cape Canaveral in Florida.

The long-anticipated flight of Euclid, an astronomical probe developed and built by the European Space Agency, looked in jeopardy last year when the war in Ukraine ended plans for it to be launched atop a Russian Soyuz rocket. But a timely switch to private launch provider SpaceX proved the key to getting the mission off the ground.

Canadian scientists are among those partnering in Euclid’s quest, which is set to begin once the spacecraft reaches its destination at ‘L2′ – a point in space 1.5 million kilometres from Earth, where NASA’s James Webb Space Telescope is also located.

But unlike Webb, which is busy making the most distant stars and galaxies in the universe visible to us, Euclid is built to explore something that will never be visible to anyone.

“Our number-one goal is focused around dark energy,” said Dr. Will Percival, an astrophysicist at the University of Waterloo in Ontario and a senior member of Euclid’s science team. “We want to understand what it is. We want to know why the expansion of the universe is accelerating.”

It’s been nearly a century since Edwin Hubble first clocked the speeds of distant galaxies and showed that space – but not the stuff in it – is getting larger at a measurable rate. The process was initiated by the Big Bang, the explosive event that gave rise to the universe.

In 1998 astronomers announced a second startling discovery. By measuring the motion of still more distant galaxies, they found that the expansion of the universe has been speeding up. The term “dark energy” was coined to put a label on the effect, but understanding exactly what dark energy is has proved far more challenging.

“It’s arguably one of the biggest mysteries we have in physics,” Dr. Percival said.

Open this photo in gallery:

Will Percival, an astrophysicist at the University of Waterloo, is the Canadian principal investigator for the European Space Agency’s Euclid mission. Behind him is a photo of the Canada-France-Hawaii Telescope, which is providing data on galaxies in support of the mission to understand the nature of dark energy.Gabriela Secara/Perimeter Institute/Handout

Theorists have speculated about the nature of dark energy and what it means for the fate of the universe. It could be that it is simply an innate kind of energy that is embedded in the vacuum of space. Hence, as the universe grows, the total amount of dark energy grows with it, exerting an outward pressure that continues to strengthen until the end of time.

In such a scenario all of the hundreds of billions of galaxies that we can see in the universe today will eventually be pushed away so rapidly that they outpace the ability of light to cross the growing gap and vanish from our sight. Each galaxy will then become an isolated island, with its stars gradually burning out like embers in the midst of an eternally deepening darkness.

As dismal as that may seem, this is the scenario that best fits what astronomers have observed thus far. But there is also a chance that a more precise reading of the phenomenon would show that dark energy is changing over time, and may even shut off at some point in the future.

To accurately measure how much space has stretched over cosmic time one needs a measuring stick. Enter Euclid – a mission aptly named after the famous geometer of antiquity.

“If you want to observe the cosmos as a whole, then you need to take a big survey,” said Giuseppe Racca, the European Space Agency’s project manager for Euclid during a media briefing last week.

The mission is designed with the big picture in mind. Over the course of its six-year mission, Euclid is expected to take in about 36 per cent of the surrounding sky as seen from our solar system to a depth of some 10 billion light years.


Euclid’s quest

A European mission with partners in Canada and elsewhere is

set to measure the expansion of the universe across cosmic

time in hopes of better understanding dark energy –

a phenomenon that has caused the expansion to accelerate.

EUCLID SPACE TELESCOPE

Euclid: Will launch

to orbit around

sun-earth Lagrange

point L2

Lagrange point L2:

Equilibrium point

of sun-earth system

is located 1.5 million

kilometres from

earth in opposite

direction of sun

Sunshield:

Blocks light

from sun,

earth and

moon

MOON

384,000 km

from earth

L2 is locked

in perfect unison

with earth’s

orbit around sun

EARTH

150 million km

from sun

Euclid’s orbit has

diameter of about

1 million km

around L2

Star trackers

graphic news, Sources: Euclid Consortium;

European Space Agency; Space.com

Euclid’s quest

A European mission with partners in Canada and elsewhere

is set to measure the expansion of the universe across

cosmic time in hopes of better understanding dark energy –

a phenomenon that has caused the expansion to accelerate.

Lagrange point L2:

Equilibrium point

of sun-earth system

is located 1.5 million

kilometres from

earth in opposite

direction of sun

EUCLID SPACE TELESCOPE

Euclid: Will launch

to orbit around

sun-earth Lagrange

point L2

Sunshield:

Blocks light

from sun,

earth and

moon

MOON

384,000 km

from earth

L2 is locked

in perfect unison

with earth’s

orbit around sun

EARTH

150 million km

from sun

Euclid’s orbit has

diameter of about

1 million km

around L2

Star trackers

graphic news, Sources: Euclid Consortium;

European Space Agency; Space.com

Euclid’s quest

A European mission with partners in Canada and elsewhere is set to measure the expansion

of the universe across cosmic time in hopes of better understanding dark energy – a phenomenon

that has caused the expansion to accelerate.

EUCLID SPACE

TELESCOPE

Euclid: Will launch to orbit around

sun-earth Lagrange point L2

1.2 m Korsch telescope:

Operates in visible and

near-infrared wavelengths

Sunshield:

Blocks light

from sun,

earth and

moon

Lagrange point L2:

Equilibrium point

of sun-earth system

is located 1.5 million

kilometres from

earth in opposite

direction of sun

MOON

384,000 km

from earth

L2 is locked

in perfect unison

with earth’s

orbit around sun

EARTH

150 million km from sun

Euclid’s orbit has

diameter of about

1 million km around L2

Star trackers

graphic news, Sources: Euclid Consortium; European Space Agency; Space.com

The depth is crucial, because Euclid is not only looking across space but back in time. And as it measures the expansion of the universe at different epochs it will cover the time period when dark energy became dominant.

To achieve this, Euclid is equipped with two instruments. One is a camera that will record the shapes of distant galaxies. This is important because galaxies appear slightly warped when their incoming light is distorted by clumps of dark matter located along the line of sight. (The nature of dark matter is another big cosmic mystery, but in this case it serves as a tool to show mass is distributed in the universe.)

Euclid’s second instrument is an infrared spectrometer and photometer that can be used to measure the motions of receding galaxies.

When combined, data from both instruments will provide a three dimensional map that shows how the expansion of the universe has changed over cosmic time.

To get a better sense of whether dark energy is constant or changing, astronomers will also need to refer to data taken over many years by ground based observatories, including the Canada-France-Hawaii Telescope on Mauna Kea. It’s these data that have allowed Canada entry into the mission, with several participating researchers at Waterloo, the University of British Columbia and other centres.

Juna Kollmeier, director of the Canadian Institute for Theoretical Astrophysics at the University of Toronto, who is not a team member, said that Euclid has the potential to advance the study of dark energy, “not only more precisely, but perhaps in a qualitatively new way.”

That would be a welcome outcome for Dr. Percival, who said he is looking forward to digging into Euclid’s expected trove of data after 10 years of preparing for the mission.

“That’s why I stuck with it,” Dr. Percival said. “It’s taking that step forward into the unknown.”

 

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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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