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5 trillion bytes a day: SpaceX engineers flash some facts about Starlink satellites – GeekWire

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An artist’s conception shows the deployment of SpaceX’s Starlink satellites. (SpaceX Illustration)

SpaceX’s Starlink satellite constellation is still deep into testing mode, but it’s already generating 5 trillion bytes of data on a daily basis and getting software updates on a weekly basis.

Those are a couple of the nuggets coming from a weekend Reddit “Ask Me Anything” session featuring SpaceX’s software team.

The main focus of the online chat was SpaceX’s successful mission sending NASA astronauts Bob Behnken and Doug Hurley to the International Space Station in a Crew Dragon capsule — but one of the team members, Matt Monson, has moved on from Dragon to take charge of Starlink software development.

Although SpaceX’s HQ is in Hawthorne, Calif., most of the work relating to the Starlink satellites is being done at the company’s facilities in Redmond, Wash.

SpaceX tends to play its satellite cards close to the vest, in part because the process of building a satellite system is “highly proprietary” — as one of the company’s vice presidents, Patricia Cooper, said in a 2016 filing with the Federal Communications Commission. For that reason, any nuggets about Starlink’s workings are avidly sought by SpaceX’s fans as well as the occasional inquiring journalist.

SpaceX employees in Redmond, Wash., give a cheer during the countdown to a Falcon 9 launch that put the company’s second batch of 60 Starlink satellites into orbit last November. (SpaceX via YouTube)

This weekend’s Reddit AMA attracted more than 7,000 questions and comments, and the engineers could reply to only a few of them. That made it easy to avoid sensitive subjects — for example, the timetable for adding satellite-to-satellite laser communication links to the constellation. Despite the limitations, Monson and the other developers shed light on Starlink’s inner workings, including these highlights:

  • The technology used for the display screens on the Crew Dragon also provided the basis for the user interface on the first two prototype Starlink satellites, launched in 2018. “It’s grown a ton since then, but it was awesome to see Bob and Doug using something that somehow felt familiar to us too,” Monson wrote.
  • SpaceX relies on the Linux operating system in its satellites as well as its rockets. “Each launch of 60 satellites contains more than 4,000 Linux computers,” Monson said. “The constellation has more than 30,000 Linux nodes (and more than 6,000 microcontrollers) in space right now. And because we share a lot of our Linux platform infrastructure with Falcon and Dragon, they get the benefit of our more than 180 vehicle-years of on-orbit test time.”
  • Not everything has gone right with Starlink’s software. “We’ve had many instances where a satellite on orbit had a failure we’d never even conceived of before, but was able to keep itself safe long enough for us to debug it, figure out a fix or a workaround, and push up a software update,” Monson wrote. He said SpaceX usually updates the software on all the satellites about once a week, “with a bunch of smaller test deployments happening as well.”
  • Monson said “we’re currently generating more than 5TB [5 trillion bytes] a day of data” for Starlink. “Doing the detection of problems onboard is one of the best ways to reduce how much telemetry we need to send and store (only send it when it’s interesting). The alerting system we use for this is shared between Starlink and Dragon.”

As of last week, SpaceX has launched eight batches of 60 Starlink satellites, forming a constellation of roughly 480 spacecraft (with a few that have gone out of service). There’s a continuing controversy over the satellites’ visibility and potential interference with astronomical observations. If the skies are clear, you can use Heavens-Above.com as your guide to spot the satellite train passing across the sky.

The broadband data network is already being tested for military applications. Just last month, SpaceX and the U.S. Army struck a deal for three more years of experimentation and evaluation. Limited commercial service could begin later this year, though it’s not yet clear exactly how the service will be marketed.

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Eventually, thousands of Starlink satellites could offer always-on broadband internet access to billions of people around the world. Other ventures, ranging from now-bankrupt OneWeb to Canada’s Telesat to Amazon’s Project Kuiper, have been going after the satellite internet market as well. But based on Monson’s comments, they’ll have a lot of catching up to do on the technical front.

Monson said his favorite moment at SpaceX came a little more than a year ago, when the first batch of 60 satellites was deployed in orbit like a deck of cards.

“We’d designed the all-at-once deployment mechanism, but it’s hard to model, and we couldn’t really be 100% sure it would work right,” he wrote. “I remember sitting there, with Falcon lifting off the pad, thinking: OK. In an hour we’re either going to be idiots for trying a thing that obviously never could have worked, or geniuses for doing the thing that’s obviously the right way to deploy lots of satellites. Luckily it went well.”

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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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