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Two Satellites Could Smash Into Each Other Over the U.S. Tonight – Gizmodo

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Artist’s conception of the decommissioned IRAS satellite.
Image: NASA

A pair of decommissioned satellites are at risk of colliding later today, potentially producing hundreds if not thousands of new pieces of space debris. Regardless of what happens, however, this incident illustrates our dire need for sensible space management practices.

Normally, operators on the ground can adjust the orbital inclination of their satellites in the event of a potential collision, but neither of these satellites is functional. One of the two, the joint NASA-Netherlands Infrared Astronomical Satellite (IRAS), weighs around 1,073 kilograms (2,366 pounds) and has been in space since 1983. The other, GGSE-4 (also known as Poppy 5B), was launched in the late 1960s by the U.S. Naval Research Laboratory and weighs 83 kg (183 lbs).

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At a relative velocity of 14.7 kilometers (9.1 miles) per second, a collision between these two satellites would generate a tremendous amount of space debris, increasing the odds of yet another collision at some point in the future. The decommissioned satellites will experience their closest approach at 6:39 p.m. ET Wednesday (January 29, 2020) in the skies above eastern North America—but don’t worry, the debris would stay in low Earth orbit (LEO).

The potential collision was detected by LeoLabs, a private company that tracks satellites and debris in low Earth orbit. The company operates three radar stations, two in the U.S. and one in New Zealand, and it can track objects as small as 10 centimeters (3.9 inches) in diameter.

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In a recent update, LeoLabs tweeted their latest assessment of the situation. The odds of a collision are back to 1 in 100, after the company had briefly assigned a 1 in 1,000 chance earlier today. The satellites will swing past each other at a distance of around 12 meters (39.5 feet)—an extremely close shave by any measure. The closest approach will happen at an altitude of 900 kilometers (560 miles) above Earth’s surface.

An even more alarming calculation from LeoLabs takes into account the 18-meter-long (59-foot) booms attached to GGSE-4. With those taken into consideration, the odds of a collision jump to 1 in 20, according to LeoLabs.

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Conceptual image of an earlier model, the Poppy 4D, with its long booms extended.
Image: NRO/USN

These odds may seem (relatively) low, but satellite operators ring the alarm bells when the odds approach 1 in 10,000. So while the chance of a collision seems slim, this is a matter of serious concern. In an email to Gizmodo, McDowell said two satellites coming this close together “is still rare” but is becoming “more frequent as LEO gets more crowded.”

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The current situation with IRAS and GGSE-4 stems from their immobile status, but McDowell said this problem will eventually extend to live satellites. Operators will have to move an increasing number of satellites to avoid collisions, which could potentially put them in the paths of other satellites “depending on the accuracy of predictions,” he said, adding that another issue will be the ability to perform one-day-ahead satellite predictions. Ideally, he hopes that satellite operators will eventually work at 10-meter (33-foot) resolutions, instead of the current 100-meter (328foot) level of accuracy. That “would help,” said McDowell, “but we don’t know how to get there.”

“There have always been close calls in space—not to mention accidental collisions—but we are certainly becoming more aware of them as our ability to identify and monitor objects in space through space situational awareness improves,” Jessica West, a program officer at Project Ploughshares and the managing editor of its Space Security Index, wrote in an email to Gizmodo. “For active satellites, this means that there is more opportunity to maneuver to avoid a close call. But for dead satellites, we are still stuck waiting and watching with our fingers crossed.”

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Chart showing unintentional collisions between space objects.
Image: Space Security Index/Jessica West

That LEO is becoming overcrowded is no secret. Figures from the U.S. Space Surveillance network shows that roughly 29,000 objects larger than 10 centimeters (3.9 inches) are currently in LEO, many of which are zipping around at speeds reaching 10 kilometers (6 miles) per second. This figure is set to increase due to the lower costs of launching objects into space and the trend toward more compact satellites. The rise of megaconstellations, such as SpaceX’s Starlink, will result in thousands more satellites.

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Sure, LEO seems vast, but the amount of space in space is somewhat of an illusion. Space and time shrink owing to the tremendous speeds involved. Space traffic is not like it is on Earth’s surface, where velocities are measured in terms of distance per hour rather than per second. Satellite motions in space are akin to watching movies in fast-forward.

McDowell described it as an n-squared problem. A 10-fold increase in the number of satellites results in a 100-fold increase in the number of close misses and actual collisions, he said, “adding that “we’re about due for one.”

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Even one collision would be bad. If IRAS and GGSE-4 smash into each other tonight, the resulting kinetic energy would blow debris into neighboring orbits, further heightening the odds of another collision. This could result in a hypothetical cascade known as a Kessler Syndrome, in which an ever-growing cloud of space debris eventually makes LEO inaccessible.

In terms of technical solutions to the problem, West says we could reduce the amount of defunct satellites in orbit by “designing them with the ability and intention to de-orbit at the end of their service lifespan.” Satellites in LEO, namely those below 600 kilometers (370 miles), will “naturally be dragged down into Earth’s atmosphere and disintegrate within 25 years,” West told Gizmodo, but “25 years is a long time—too long given the intensity to which we are using this orbit and the tens of thousands of new satellites potentially being launched.”

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That said, IRAS and GGSE-4 are much higher, around 800 kilometers (500 miles), an altitude in which objects “will remain in orbit for decades unless intentionally de-orbited, which is not the norm,” said West.

Several initiatives are currently underway to devise ways of decluttering LEO, but these solutions come with their own drawbacks, including tremendous costs and numerous safety considerations. Ultimately, West says this latest incident “points to the need for better, global governance of activities in outer space.”

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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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