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Why SpaceX's Starlink Satellites Caught Astronomers Off Guard – Space.com

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Astronomers have had five years to brace for the impact of SpaceX’s Starlink internet-satellite megaconstellation, but the first few batches of the spacecraft still managed to catch the community off guard.

SpaceX founder and CEO Elon Musk announced the Starlink concept (though not the name) back in January 2015, explaining that the company intended to launch about 4,000 broadband satellites to low Earth orbit to provide low-cost internet service to people around the world. 

The envisioned numbers have grown since then. SpaceX now has permission from the U.S. Federal Communications Commission to loft about 12,000 Starlink craft, and the company has applied to an international radio-frequency regulator for approval of up to 30,000 additional satellites. (For perspective: There are only about 2,000 operational satellites in orbit today, and humanity has launched fewer than 9,000 craft into space in all of history, according to the United Nations’ Office of Outer Space Affairs.)

Related: In Photos: SpaceX Launches Third Batch of 60 Starlink Satellites

Nearly 200 Starlink craft are already circling Earth. SpaceX lofted the first batch of 60 satellites last May and performed similar launches in November and this past Monday (Jan. 6). 

These three missions have been eye-opening for skywatchers and professional astronomers alike. Shortly after deployment, the Starlink craft look like a bright string of pearls as they race together across the sky. This formation disbands as the 500-lb. (225 kilograms) satellites disperse and climb to their final operational altitude about 340 miles (550 kilometers) above Earth’s surface — but the individual spacecraft remain visible to the naked eye, even way up there.

“What surprised everyone — the astronomy community and SpaceX — was how bright their satellites are,” Patrick Seitzer, an astronomy professor emeritus at the University of Michigan, said Wednesday (Jan. 8) during a special news conference at the 235th meeting of the American Astronomical Society (AAS) called “Astronomy Confronts Satellite Constellations.” 

Related: SpaceX’s 1st Starlink Satellite Megaconstellation Launch in Photos

“We knew these tens of thousands(-strong) megaconstellations were coming, but based on the sizes and shapes of things currently in orbit, I thought maybe 8th or 9 magnitude,” Seitzer added. “We were not expecting 2nd or 3rd magnitude in the parking orbits, and we certainly not expecting 4th to 5th magnitudes in the [operational] orbits.”

The magnitude scale used by astronomers assigns lower numbers to objects that appear brighter in the sky. For example, the brightest object in our sky, the sun, has a magnitude of minus 27, whereas the faintest objects you can see with binoculars are around plus 10. Only objects about plus 6 or brighter can be seen by the naked eye under clear, dark skies.

This surprising brightness has many astronomers worried. The huge number of coming Starlink satellites — and SpaceX plans to launch nearly 1,600 more just by the end of this year — could severely compromise the ability of ground-based scopes to do their work, some researchers have said.

The high-profile project most likely to be affected, Seitzer said, is the Vera Rubin Observatory. This big instrument, which was until Monday known as the Large Synoptic Survey Telescope (LSST), is scheduled to come online a few years from now in the Chilean Andes. 

“The survey is the most impacted by bright satellite trails because of its wide field of view and extreme sensitivity,” Seitzer said, citing a statement provided to him by Vera Rubin Observatory chief scientist Tony Tyson. “The original Starlinks will saturate the LSST’s detectors.”

But Starlink’s effects will be felt beyond the astronomical research community —  indeed, by pretty much everyone around the world, dark-sky advocates have stressed. The star-filled night sky is an international resource and one of the only ways that many people commune with nature in our increasingly urban and technological world, said Ruskin Hartley, executive director of the International Dark Sky Association. So, we should think hard about how we manage that resource, he said.

“The night sky is the ultimate public good; it’s our ultimate commons,” Hartley said during Wednesday’s news conference. “No one individual can protect it. And the flip side, I believe, [is] no one individual should be allowed to despoil that.”

Astronomers have voiced their concerns to SpaceX and found a receptive audience, said Jeffrey Hall, the director of Lowell Observatory in Flagstaff, Arizona. 

Related: Elon Musk, Revolutionary Private Space Entrepreneur

“We have not had to cajole SpaceX in any way; they’ve been very receptive, very proactive, in holding roughly monthly telecons with us,” Hall said during Wednesday’s news conference. 

So far, he added, those telecons have mostly been informational, telling the astronomical community when the company plans to launch and deploy more Starlink satellites, and into which orbits. 

“It’s been a little more staying in touch than making a lot of progress on mitigation,” Hall said. (He added that astronomers plan to speak soon with OneWeb, which has launched the first half-dozen members of its own big internet-satellite constellation. A few other companies, including Amazon, are planning similar networks of their own, but none will be as big as SpaceX’s is envisioned to become.)  

But SpaceX representatives have expressed a desire to mitigate, and they’ve recently taken some action toward this end. For example, Patricia Cooper, SpaceX’s vice president of satellite government affairs, presented a paper during the special AAS scientific session about megaconstellations on Wednesday (though the company didn’t participate in the news conference that day). 

And one of the 60 spacecraft that launched on Monday sported a special coating designed to reduce its brightness. If everything goes well, and the coating doesn’t seriously affect the satellite’s performance (through increased solar heating, for example), this mitigation measure could eventually become widespread across the Starlink fleet.

Not everyone is satisfied by such steps. Consider the question asked by astrophysicist and science communicator Ethan Siegel, who was in the audience at Wednesday’s news conference.

“I apologize for this question, because I’m having difficulty controlling my fury at this situation,” Siegel began. “Why should astronomers trust SpaceX — which knows about this [brightness] problem but is deliberately worsening this instead of addressing it before additional launches — instead of seeking a legal or international mandate for regulation? Are we Elon Musk’s Neville Chamberlain?”

In response, Hall explained that the astronomy community doesn’t really have much choice.

“The launches are underway right now. I think regulation of the Wild West up there is necessary; that is going to take a great deal of time to implement, just because of the nature of that beast,” Hall said.

“Therefore, there is no advantage or upside to distrusting what SpaceX colleagues have told us,” he added. “We will simply take them at face value and work as best as we can and honestly with them to try to solve the situation. They are on the record saying they want to solve the situation for astronomy. We are working to identify the targets they will need to hit to make that happen, and then we’ll see what happens.”

Mike Wall’s book about the search for alien life, “Out There” (Grand Central Publishing, 2018; illustrated by Karl Tate), is out now. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook

Need more space? Subscribe to our sister title “All About Space” Magazine for the latest amazing news from the final frontier! (Image credit: All About 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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