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ATLANTIC SKIES: How big is the universe? – TheChronicleHerald.ca

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The joy of my life, my granddaughter Scarlet, asked me the other day, “Poppy, how big is the universe?”

Her boundless curiosity never ceases to amaze me. I attempted to explain to her, as best I could to an eight-year-old who has never travelled further than Halifax, N.S., that the universe, as we currently understand it, is very large – so large, in fact, that we have to measure it, not in terms of kilometers, but, rather, in light-years. Even then, the numbers are extremely big.

I am not sure my explanation of exactly what a light-year is (how far light travels through space in the course of one year, or approximately 9.5 trillion kilometers), and, how when multiplied by how far (in light-years) we can see out into space, did much to answer her initial query, as the resulting silence and quizzical expression on her face told me she couldn’t really grasp such distances (who can blame her?).

Her response just about summed up what, I imagine, most people would say: “Guess that really is pretty big, isn’t it, Poppy?”

“Yes, my darling, it certainly is,” I replied.

In the 1920s, the American astronomer, Edwin Hubble (after whom the Hubble Space Telescope is named) and his assistant, Milton Humason, proved that the galaxies they were studying and photographing were, in fact, moving outward as viewed from Earth, or receding, into deep space, and further, that the more distant the galaxy, the faster it was receding. This became known as Hubble’s Law.

Hubble’s discovery actually grew out of earlier work by Albert Einstein, who, in 1917, predicted that the universe was expanding, because space itself was expanding. Although, at the time, Einstein wasn’t confident enough in his expanding universe theory to publish it, it later formed the basis for his famous General Theory of Relativity.

When I use the term “universe” here, I mean the observable universe, the farthest point that we can see out into space with our best astronomical telescope – the Hubble Space Telescope (HST). In 2016, the HST photographed what, to date, is the most distant object – the galaxy GN-z11. Taking the expansion of the universe into consideration, it is approximately 32 billion light-years, or approximately 3.04 sextillion (3.04 followed by 21 zeros) kilometers away; a truly mind-boggling distance.

However, astronomers theorize that the actual universe is much, much larger. Starting at the moment of the universe’s theoretical creation (called the “Big Bang”, though not an actual explosion), the accepted age of the universe is now thought to be approximately 13.8 billion years. As the universe continues to expand, the most distant point in space from which we will ultimately receive light back from distant galaxies (which are increasingly moving away from us), known as the “cosmic horizon”, is estimated to be about 46 billion light-years away.

It is theorized that, due to the increasingly rapid rate of expansion of the universe as a whole, we will never see any light from objects beyond the cosmic horizon. However, when the James Webb telescope (a much larger and more sophisticated telescope than the HST) is launched on Oct. 31, 2021, the boundaries of the known universe will, undoubtedly, be extended.

Though the above distance figures are truly mind-blowing. and may make you feel incredibly small, it should, at the very least, underscore just how unique our life-bearing planet Earth is in the great infinite vastness of the cosmos and how wonderfully precious it is to have children and grandchildren who challenge you to think about it.

This week’s sky

Mercury remains too close to the sun to be visible this coming week. Venus (magnitude -4.2) is visible, as it has been these past few weeks, in the pre-dawn sky. It rises around 2:45 a.m., reaching its highest point at 34 degrees above the eastern horizon, before fading from sight as dawn breaks around 6:15 a.m.

Mars (magnitude -1.8) is visible in the early morning sky, rising in the east around 10:30 p.m., and achieving its highest altitude (50 degrees) above the southern horizon by about 4:20 a.m., before becoming lost in the dawn twilight by 6:15 a.m.

Jupiter and Saturn remain early evening objects, both visible side-by-side (bright Jupiter to the right) above the southeast horizon by about 8:30 p.m. Jupiter (magnitude -2.58) disappears from view around 12:40 a.m., when it sinks below seven degrees above the southeast horizon, followed by Saturn (magnitude +0.31) around 1:30 a.m., when it sinks below 10 degrees above the southwest horizon.

When the full moon closest to the Autumnal Equinox (Sept. 22), occurs in October, as it does this year on Oct. 1, it is known as the “Harvest Moon”. September’s Full Moon (Sept. 2) is referred to as the “Corn Moon,” the name given to it by Native American tribes, as this was when they usually harvested their corn crops.

Until next week, clear skies.

Events:

  • Sept. 2 – Full (corn) moon
  • Sept. 6 – Moon at apogee (farthest from Earth)

Glenn K. Roberts lives in Stratford, P.E.I., and has been an avid amateur astronomer since he was a small child. He welcomes comments from readers at glennkroberts@gmail.com.

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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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