Bennu asteroid will come very close to Earth, but scientists say not a reason for concern. - The Washington Post | Canada News Media
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Bennu asteroid will come very close to Earth, but scientists say not a reason for concern. – The Washington Post

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It’s not the plot of another doomsday movie. Yet there is a pending, albeit unlikely, threat to life as we know it: an asteroid approaching Earth.

Bennu, a rugged, rock-spewing asteroid with a diameter of about one-third of a mile, is headed in our direction, on track to come very close to Earth in September of 2135.

But not to panic, scientists with NASA said Wednesday. Though Bennu will come within half the distance of the moon, the odds of the asteroid colliding with Earth in the next century and causing Armageddon-type of destruction are still very low.

“Even though there is no possibility whatsoever of in impact during that encounter, Bennu is going to be fairly close to the Earth,” said Davide Farnocchia, a scientist with the Center for Near Earth Object Studies, a NASA center that calculates asteroid and comet orbits and their odds of impact at the Jet Propulsion Laboratory in Southern California.

Although researchers believe Bennu will not impact Earth, they now face the challenge of deciphering how our planet’s gravity will alter the asteroid’s path around the sun, NASA scientists said in a conference call with reporters Wednesday.

Scientists noted there is small possibility that the asteroid could pass through what’s known as a “gravitational keyhole” that could put it in en route to Earth at a later date in the 22nd century. A gravitational keyhole is a tiny region in space where a planet’s gravity can tweak the trajectory of a passing asteroid and put it on a path to collide with it in the future.

Farnocchia said that although recent findings show the odds of impact have slightly increased — from 1 in 2,700 to 1 in 1,750 over the next century — it “does not represent significant change,” or a reason to worry.

Farnocchia explained that scientists now have a much better idea of Bennu’s path thanks to data collected by NASA’s Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft, which orbited and studied the asteroid for over two years.

“Overall the situation has improved,” Farnocchia, the lead author of a study published Wednesday, told reporters in a conference call. “I am not any more concerned about Bennu than I was before; the impact probability remains very small.”

In the study, NASA researchers used precision-tracking data from the OSIRIS-REx spacecraft to better understand Bennu’s movements through 2300, improving scientists’ ability to determine the probability of impacting Earth and predict the orbits of other asteroids.

Using NASA’s Deep Space Network of giant radio antennas that support interplanetary spacecraft missions and computer models, scientists were able to determine Bennu’s overall probability of striking is about 1 in 1,750 (or 0.057 percent.)

Looking at it from a glass-half-full perspective, it means there is a 99.94 percent probability that Bennu will not hit our planet.

Scientists also calculated the day with the highest risk of collision: Sept. 24, 2182, with a probability of 1 in 2,700 (or about 0.037 percent) — which is still lower that the overall probability of impact through 2300.

The potentially hazardous asteroid was discovered in 1999 by the Lincoln Near-Earth Asteroid Research Team, a program that works on detection and tracking, and has been closely observed with 580 ground-based “astrometric observations,” mainly made by optical and radar telescopes through 2018, according to the study published in Icarus Journal.

Since its discovery, Bennu has had three close encounters with Earth, in 1999, 2005 and 2011, during which two radar stations collected data of the asteroid’s measurements.

Although the chances of it colliding with Earth are very low, Bennu remains one of the two most hazardous known asteroids in our solar system, along with another called 1950 DA, NASA said in a news release.

Researchers stated that the most pressing threat for Earth from space objects are hazardous asteroids that are undetected. However, they said they have detected about 60 percent of those similar in size to Bennu.

In 2016, NASA launched the OSIRIS-REx spacecraft to fly in close proximity to Bennu to gather information about its size, shape, mass, and composition, while monitoring its spin and orbital trajectory to evaluate its potential danger.

After a 27-month-long journey, OSIRIS-REx arrived in the asteroid’s orbit in 2018 and spent two years closely studying the object, before coming back to earth on May 10 of this year.

“The OSIRIS-REx data give us so much more precise information, we can test the limits of our models and calculate the future trajectory of Bennu to a very high degree of certainty through 2135,” said Farnocchia. “We’ve never modeled an asteroid’s trajectory to this precision before.”

The spacecraft also scooped up a sample of rocks and dust from the asteroid’s surface, which it will drop to Earth two years from now, on Sept. 24, 2023, landing in Utah’s Great Salt Lake Desert.

“The orbital data from this mission helped us better appreciate Bennu’s impact chances over the next couple of centuries and our overall understanding of potentially hazardous asteroids — an incredible result,” said Dante Lauretta, OSIRIS-REx principal investigator and professor at the University of Arizona.

“The spacecraft is now returning home, carrying a precious sample from this fascinating ancient object that will help us better understand not only the history of the solar system but also the role of sunlight in altering Bennu’s orbit since we will measure the asteroid’s thermal properties at unprecedented scales in laboratories on Earth,” he said, according to the news release.

A week after the spacecraft entered its first orbit around Bennu, on Dec. 31, 2018, the mission’s team came to the surprise realization that the asteroid was releasing small pieces of rock into space.

OSIRIS-REx is not the only spacecraft from Earth exploring an asteroid. Hayabusa2, launched by Japan’s space agency in 2014, began orbiting the near-Earth asteroid Ryugu in 2018 and in 2020 successfully completed its mission to collect samples and return them to Earth — according to the Japan Aerospace Exploration Agency.

Traveling at approximately 600 miles per hour, Bennu would unleash the energy of more than a billion tons of TNS if it were to crash into Earth, according to NASA’s calculations.

The resulting damage depends on a number of factors and specific circumstances, including location and angle of entry into our atmosphere, but it could create a crater three to six miles in diameter, said Lindley Johnson, NASA’s planetary defense officer. The area of devastation would be much bigger: as much as 100 times the size of the crater.

If an object Bennu’s size hit the Eastern Seaboard, it “would pretty much devastate things up and down the coast,” he told reporters.

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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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