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ATLANTIC SKIES: Is it a UFO? Low-Earth orbit satellites cluttering up night sky for stargazers – TheChronicleHerald.ca

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Anyone who has spent time observing the night sky has noticed tiny, bright, pin-point spots of light speeding across the heavens, often appearing and disappearing at random.

Though some may think they are UFOs, most people know these are man-made satellites, launched into low-Earth orbit (LEO) for a variety of communication, research, and surveillance purposes.

For the most part, unless you happen to be taking a time-exposure photo of the night sky, they are of no consequence to the average observer, merely an interesting and unexpected surprise. Since they are so high up, very tiny, and rather dim, most pass overhead unseen.

That is about to change. In 2019, space entrepreneur Elon Musk launched the first 60 SpaceX Starlink satellites into LEO, followed by more launches throughout 2020.

The 17th launch occurred Jan. 20, bringing the current number of Starlink satellites into orbit around the Earth to over 1,000 – that’s in addition to the 3,000 satellites already in orbit. SpaceX has already received permission from the US Federal Communications Commission (which oversees communication networks across multiple industries, and thus most global satellite launches) to put 12,000 more Starlink satellites into orbit, with plans to have more than 30,000 eventually in orbit.

Other companies, notably Amazon and OneWeb, have jumped onto the trillion-dollar worldwide internet-connectivity market bandwagon, with plans to launch 3,236 and 2,000 satellites respectively.

SpaceX hopes to capitalize on its “rideshare” program that will assist other national and international commercial and government customers to cheaply put their satellites into orbit by collectively sharing the launch costs. SpaceX’s stated purpose is to bring high-speed broadband internet access to places on the globe not currently served by other communication technologies, although current analysis indicates the cost of internet access in most of these areas would be prohibitive – something that has an estimated $30 billion annual revenue for SpaceX.

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Astronomical issue

The potential problem that 35,000-plus satellites pose to astronomers is significant. When Starlink satellites are launched in groups, they spread out into what are referred to as satellite “trains” or “constellations” – long strings (like a pearl necklace) of lights crossing the night sky at an altitude of 550 kilometres.

Like all satellites, the Starlink satellites are made of metal – highly reflective – and, when lit by sunlight, shine like a “moving star”, significantly and negatively impacting both amateur and professional observations and research. Time exposure astrophotography for professional observation and research purposes is jeopardized when the constellations of satellites obscure the object being viewed, and the astrophoto ruined. Another significant problem is the potential interference with NASA’s observation of near-Earth asteroids, leaving our planet vulnerable to potential world-altering impacts when the telescopes watching for the asteroids are confused by the light of the moving satellites.

To its credit (but only after loud complaints from the global astronomy community), SpaceX is trying to come up with a means of either dimming or eliminating the brightness of the satellites by shielding them with a sunshade or dimming them with an anti-reflective coating; such measures, however, will take time to assess; and, in the meantime, the launches continue.

Space junk

In addition to the light polluting problem with all these satellites, they also contribute to the enormous amount of “orbital debris” or “space junk” circling the planet. There are currently more than half a million pieces of space debris being tracked by NASA – about 21,000 are larger than a softball, and over 500,000 are the size of a marble or larger, with millions of pieces too small to be tracked. Add to this number an additional 35,000-plus satellites zipping around at 28,000 kms/hour, and you can well imagine the increased potential for what scientists refer to as the “Kessler Syndrome” – where collisions between satellites or space debris cause a runaway cascade of collisions, resulting in the destruction of or damage to many satellites or other spacecraft.

These collisions could add countless more pieces of orbital debris to the already huge number of orbiting debris pieces, compounding the problem further. Such collisions and the resulting space debris could pose significant threats to the International Space Station, future commercial space flights, and even future missions to the moon and Mars. Large satellites and large debris objects, if knocked earthward, could pose a threat to people on the ground if they survive re-entry and strike a populated area.

Though many people don’t care about additional bright lights streaking across the night sky, there is much to be lost if it becomes saturated with artificial lights. Not only will valuable scientific observations and research opportunities be compromised, but sadly, our historical connection to the night sky will be lost. From the nights when early humans first pondered the mysteries of the heavens to the elaborate stories and myths ancient civilizations associated with the constellations and the contributions astronomy has made to the advancement of science, we have always been connected spiritually and emotionally to the stars. We are, after all, made of stardust; naturally, we have an affinity for them. To lose this connection for the sake of artificial entertainment is lamentable.


This week’s sky

As with last week, planet observations this coming week are limited. Mercury, Venus, Jupiter, and Saturn are all too close to the sun to be readily observable. Mercury will achieve inferior conjunction with the sun on Feb. 8.

The only planet observable this week is Mars. Shining at magnitude +0.5 in Aries – the Ram, the red planet becomes accessible shortly before 6 p.m., 60 degrees above the southern horizon, remaining observable until about 12:15 a.m., when it drops below 10 degrees above the western horizon.

NASA’s Mars 2020 spacecraft, with its Perseverance Rover, is due to arrive at the planet on Feb. 18.

Until next week, clear skies.


Events

  • Feb. 3 – Moon at perigee (closest to Earth)
  • Feb. 4 – Last quarter moon

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 [email protected].

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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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