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Atlas 5 launch caps deployment of ultra-secure military communications network – Spaceflight Now

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An Atlas 5 rocket fired off pad 41 at Cape Canaveral at 4:18 p.m. EDT (2018 GMT) Thursday. Credit: United Launch Alliance

The sixth and final satellite in the U.S. military’s most secure satellite communications fleet lifted off from Cape Canaveral Thursday aboard a United Launch Alliance Atlas 5 rocket, extending the network’s expected lifetime beyond 2030.

The 197-foot-tall (60-meter) Atlas 5 rocket fired off pad 41 at Cape Canaveral Air Force Station at 4:18 p.m. EDT (2018 GMT) Thursday. The fiery start to the mission was delayed more than an hour for ULA teams to troubleshoot a problem with a ground hydraulics controller, which triggered a last-minute hold in the day’s first countdown.

The technical concern was cleared before the end of Thursday’s two-hour launch window, and the countdown resumed for another launch attempt. At T-minus 2.7 seconds, the rocket’s kerosene-fueled RD-180 engine flashed to life, followed seconds later by ignition of five strap-on solid rocket boosters.

The Atlas 5 climbed away from the launch pad with some 2.6 million pounds of thrust, turning east over the Atlantic Ocean with the U.S. military’s sixth Advanced Extremely High Frequency communications satellite.

The launcher’s boosters — made by Aerojet Rocketdyne — burned out and jettisoned less than two minutes after liftoff, followed by separation of the Atlas 5’s Swiss-made payload fairing. Four-and-a-half minutes into the mission, the Atlas 5’s first stage Russian-built main engine shut down, and stage separation occurred seconds later.

The Atlas 5’s Centaur upper stage ignited its RL10C-1 engine for the first of three burns to inject the AEHF 6 satellite into a unique, high-altitude transfer orbit on the way to a final operating post more than 22,000 miles (nearly 36,000 kilometers) over the equator.

Thursday’s mission marked the 500th production RL10 engine to be flown. RL10 engines, which burn liquid hydrogen and liquid oxygen propellants, have flown on Atlas, Saturn and Titan rockets, sending spacecraft toward every planet in the solar system.

After the Centaur’s second burn — around a half-hour after liftoff — the rocket released a small suitcase-sized CubeSat secondary payload named TDO 2.

Sponsored by the Air Force Research Laboratory and produced at the Georgia Institute of Technology, the TDO 2 spacecraft is based on a 12U CubeSat design. Its mission will support “space domain awareness” through optical calibration and satellite laser ranging, according to the U.S. Space Force’s Space and Missile Systems Center.

After deploying the TDO 2 payload, the Centaur coasted for five hours before reigniting the RL10 engine for a third time to reshape the rocket’s orbit. The final RL10 burn occurred at an altitude of around 22,000 miles (35,000 kilometers).

The planned 88-second burn raised the orbit’s perigee, or low point, and reduced its inclination. The maneuver placed the AEHF 6 spacecraft closer to its operating orbit, reducing the satellite’s expected fuel usage and extending its usable lifetime.

At 9:59 p.m. EDT (0159 GMT), the Centaur stage released the AEHF 6 spacecraft. Minutes later, satellite-builder Lockheed Martin confirmed ground teams were receiving signals from the new satellite.

“We are thrilled to accomplish this important milestone on the last AEHF satellite,” said Col. John Dukes, senior materiel leader for the geosynchronous orbit division of SMC’s production corps. “The combined integrated team worked diligently to ensure the success of this mission. The satellite is operating as expected and is ready to undergo orbit raising and on-orbit testing for the next several months after which it will provide mission critical capabilities to our warfighters.”

The AEHF 6 satellite was encapsulated inside the Atlas 5 rocket’s payload fairing in February ahead of Thursday’s launch. Credit: United Launch Alliance

The successful launch Thursday marked the first deployment of a U.S. Space Force payload since the formal establishment of the new military service in December. The AEHF satellites were previously managed the Air Force, and the first five launched on Atlas 5 rockets from Cape Canaveral beginning in August 2010.

The Space Force remains part of the Air Force, but the new service took over units formerly under the authority of Air Force Space Command.

“Congratulations to the U.S. Space Force on liftoff of your first mission,” said Tory Bruno, ULA’s president and CEO, in a statement. “We are proud to be your partner for this historic mission and honored to have launched the entire Lockheed Martin produced AEHF constellation on Atlas 5 rockets. We understand the critical importance of delivering protected communications to strategic command and tactical warfighters operating on ground, sea and air.”

U.S. military satellite tracking data indicated the AEHF 6 spacecraft separated from the Centaur upper stage in an elliptical transfer orbit ranging between 6,767 miles (10,891 kilometers) and 21,492 miles (35,313 kilometers), with an inclination of 13.7 degrees to the equator.

Those orbit figures were very close to pre-launch predictions. The RL10’s final burn before deploying the AEHF 6 satellite was programmed to continue until sensors detected a low propellant level on the Centaur stage, ensuring the payload reached the best orbit possible.

The AEHF 6 satellite will use its own engine and plasma thrusters to maneuver into a circular geostationary orbit more than 22,000 miles over the equator, where the craft’s speed will match the rate of Earth’s rotation. That will allow AEHF 6 to remain over the same part of the world 24 hours per day.

Military officials have not disclosed the geographic coverage area for AEHF 6.

Designed to operate at least 14 years, the AEHF satellites are follow-ons to the Air Force’s Milstar satellite network.

Each of the AEHF satellites, which are spread around the world to enable global coverage, provides more capacity than the entire five-satellite Milstar constellation, which launched in the 1990s and 2000s. The AEHF satellites are cross-linked with one another, allowing the network to beam signals around the world without going through a ground station.

AEHF 6 will go straight into operations once it passes post-launch tests, Space Force officials said.

The AEHF satellites provide connectivity at different specified data rates between 75 bits per second to 8 megabits per second. Those data rates are slow by modern standards, but what distinguishes the AEHF satellites is their ability to resist jamming and continue operating, even in the event of nuclear war.

Each satellite also carries gimbaled dish antennas to reach users on-the-move, phased array antennas with beams can be steered electronically rather than mechanically, and nulling antennas to provide “extremely high anti-jam capability to in-theater users,” according to Northrop Grumman, supplier of the AEHF communications payload.

“AEHF, if we were to have to operate in (the highest bandwidth) mode, will enable the President of the United States, national leaders and four international allies to be able to communicate in voice-recognizable communication, even through any event,” Dukes said.

The governments of Australia, Canada, the Netherlands and the United Kingdom have joined the AEHF program.

“Across the globe, we have numerous Army, Navy, Air Force, and joint international partner terminals with the AEHF constellation online,” Dukes said. “We have enough bandwidth to service all the terminals in our concept of operations. So by upgrading from the Milstar to the AEHF constellation, we’re able to provide that capability from now to beyond 2030.”

Thursday’s launch went ahead amid the coronavirus pandemic, which has forced delays in many upcoming launches.

But the launch of the AEHF 6 satellite was deemed critical by military leaders.

“There are critical things or mission-essential things that the U.S. Department of Defense does every day, regardless of what the current global situation is,” said Lt. Gen. John “JT” Thompson, commander of the Space and Missile Systems Center at Los Angeles Air Force Base. “So even in the face of a global pandemic like the COVID-19 crisis, we must continue to perform mission-essential tasks.

“One of those mission-essential tasks, one of those things that we have to do for the warfighter and for the United States of America is launch AEHF 6,” Thompson said. “It is designated mission-essential, and it’s because the AEHF constellation supports the President of the United States, other national leaders and the joint forces with critical strategic communications around the planet.

“This particular launch extends that capability out into the timeframe beyond 2030,” Thompson said.

ULA says its next Atlas 5 launch is scheduled for May, when the next flight of the military’s X-37B spaceplane is scheduled for takeoff from Cape Canaveral.

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Follow Stephen Clark on Twitter: @StephenClark1.

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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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