United Launch Alliance’s (ULA) Delta IV Heavy rocket made its last West Coast launch on Saturday, carrying out a mission for the National Reconnaissance Office, as it moves one flight closer to retirement. Liftoff of the NRO Launch 91 (NROL-91) mission from Space Launch Complex 6 — at the Vandenberg Space Force Base in California — took place at 3:25 PM PDT (22:25 UTC).
Delta IV Heavy is the most powerful version of the Delta IV, one of two rockets developed under the US Air Force’s Evolved Expendable Launch Vehicle (EELV) program to meet the US Government’s launch needs in the early 21st century. Delta IV, alongside its former competitor-turned-stablemate Atlas V, is now being phased out as a new generation of launchers prepare to take their place.
One of the first steps in that transition was winding down Delta IV operations, with the last Delta IV Medium+ launch taking place in 2019. Delta IV Heavy, with its significantly higher payload capacity, has been kept in service to carry out a handful of national security launches that cannot be performed by Atlas V.
Saturday’s mission, NROL-91, is the final Delta IV launch from California’s Vandenberg Space Force Base, with the rocket’s remaining missions to be executed from the East Coast at Cape Canaveral.
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While the National Reconnaissance Office (NRO) keeps details of its satellites classified, the use of a Delta IV Heavy and the fact the launch is taking place from Vandenberg speak volumes. Delta IV Heavy missions carry satellites that have too great a mass for the most powerful Atlas V configurations to place into their destined orbits, indicating the satellite is very heavy, bound for a high orbit, or both. From its location on the West Coast, Vandenberg is an ideal launch site for low Earth orbit (LEO) reconnaissance satellites operating in polar and near-polar orbits, as well as some signals intelligence satellites in elliptical orbits.
Those signals intelligence satellites are typically launched by smaller rockets, so the combination of rocket and launch site suggests that NROL-91 will deploy one of the agency’s large imaging satellites, part of a program identified in previously leaked documents as Crystal. The NRO does not acknowledge the names or types of satellites it operates; instead, they are assigned an NROL designation prior to launch and a numerical USA designation upon reaching orbit. The satellite launched by the NROL-91 mission is expected to take on the designation USA-337, the next available number in this sequence.
Crystal, also known as KH-11, is the successor to a long line of Keyhole reconnaissance satellites that the NRO has operated since the 1960s. Earlier members of this series used small capsules to return photographic film to Earth for development. When it was introduced in 1976, the KH-11 did away with these, instead downlinking images electronically. Since then, the satellites have undergone further upgrades, with several different blocks of spacecraft identified.
NROL-91 will be the nineteenth Crystal satellite to be launched, and the fifth to fly aboard a Delta IV. Previous satellites had flown aboard Titan rockets, initially the Titan III(23)D and Titan III(34)D, and later the Titan IV. The fourteenth KH-11, USA-186, was the payload for the final Titan IV launch and was at the time also expected to be the last Crystal satellite. Failures in the procurement of the successor Future Imagery Architecture (FIA) saw additional Crystal spacecraft constructed, with the first bearing a conspicuous phoenix on its mission patch.
Declassified image taken by a KH-11 satellite, showing Iran’s Semnan launch site (Credit: NRO/US Government)
The Crystal satellites are believed to give the NRO its highest-resolution pictures of the Earth’s surface. They are rumored to resemble the Hubble Space Telescope but pointed toward the Earth, rather than out into space. Most have operated in a Sun-synchronous orbit (SSO) — a particular type of low, near-polar, orbit that allows them to cover most of the Earth’s surface, ensuring they pass over each point at the same local solar time every day, ensuring consistent lighting conditions.
Up until now, the only KH-11 not operated in Sun-synchronous orbit has been USA-290. Deployed by the NROL-71 mission in January 2019, it was the last-but-one KH-11 to launch prior to NROL-91. With an orbital inclination of 73.6 degrees, its orbit is lower than the other operational satellites, meaning that it does not pass as close to the Earth’s poles.
Hazard areas published ahead of the NROL-91 mission, to warn aviators and mariners to stay away from areas where debris from the launch is expected to fall, suggest that this mission is targeting the same inclination as USA-290, rather than the more typical SSO.
With Saturday’s launch marking the last Delta IV flight from Vandenberg, it is not clear whether this also means that NROL-91 was the final launch of a Crystal satellite. The now-abandoned optical element of the FIA program sought to develop a smaller, cheaper high-resolution imaging satellite using more modern technology. Future missions could follow this model, or alternatively, Crystal satellites could continue launching aboard a different rocket — such as Falcon Heavy or ULA’s next-generation vehicle, Vulcan.
Delta IV during rollout from the Horizontal Integration Facility to the launch pad ahead of the NROL-91 mission (Credit: United Launch Alliance)
The Delta IV Heavy is a two-stage expendable launch vehicle, with its first stage consisting of three Common Booster Cores (CBCs). A five-meter-diameter Delta Cryogenic Second Stage (DCSS) sits atop this, with the satellite housed within the payload fairing at the top of the rocket. Both stages of the rocket use cryogenic propellants: liquid hydrogen and liquid oxygen.
First flown in November 2002, Delta IV has made 42 flights prior to the NROL-91 mission, of which 13 have used the Heavy configuration. Other versions of the Delta IV have included the long-retired Delta IV Medium, which consisted of a single CBC, a four-meter DCSS, and several intermediate Medium+ configurations which augmented the Medium’s CBC with two or four solid rocket boosters and could fly with either version of the second stage.
Of the previous 42 missions, Delta IV has completed 41 successfully. Its only failure was the maiden flight of the Delta IV Heavy in 2004, during which all three CBCs shut down prematurely due to cavitation in the propellant lines. The rocket, which was carrying a mass simulator and a pair of small satellites, reached a lower orbit than had been planned.
Each Common Booster Core is powered by an Aerojet Rocketdyne RS-68A engine, capable of providing 312 kilonewtons of thrust at sea level. The upper stage and payload are mounted above the center core, while the others are attached to the port and starboard sides of the vehicle.
While the CBCs provide an initial boost through Earth’s atmosphere, the DCSS is responsible for completing the insertion of the NROL-91 payload into orbit. It is powered by a single cryogenic engine from Aerojet Rocketdyne’s RL10 family.
The NROL-91 payload, encapsulated in its fairing, is installed atop the rocket (Credit: United Launch Alliance)
Although the Delta IV program is being wound down, Saturday’s launch marks the first flight of a new engine variant, the RL10C-2-1, which replaces the RL10B-2 used on previous Delta IV missions. The RL10C was developed to reduce production costs by increasing standardization between the RL10A engines used on Atlas and the RL10Bs used on Delta. The RL10C-2-1 is expected to be used on the remaining Delta IV launches, as well as future Space Launch System (SLS) missions with the Interim Cryogenic Propulsion Stage (ICPS), which is derived from DCSS.
For NROL-91, Delta IV flew with a bisector, or two-part, payload fairing made of composite materials. This is one of two fairings that can be flown on Delta IV Heavy and has been used on previous Crystal launches. Most other national security missions have used a trisector — three-part — design of metallic construction, derived from a fairing previously used on the Titan IV.
Delta IV launches from Vandenberg Space Force Base take place from Space Launch Complex 6 (SLC-6), and with Saturday’s launch marking the last Delta IV mission from Vandenberg, this is expected to be the last time the complex is used in its current configuration. With no launch providers having made public plans to use SLC-6 going forward, the complex will likely be decommissioned and mothballed in the immediate future, closing another chapter in the eventful history of this launch pad.
SLC-6 was originally built in the 1960s but did not see a launch until 1995, after the first two programs that were meant to use it were both canceled at late stages of development. The first of these was the Titan IIIM, an upgraded version of the Titan III rocket that was to have launched the Manned Orbiting Laboratory (MOL), a crewed reconnaissance platform developed by the US Air Force. Construction of the launch complex began in March 1966 and was nearing completion when MOL was abandoned in 1969.
After MOL’s cancellation, SLC-6 was selected as a launch site for Space Shuttle missions to polar orbit. Such orbits could not safely be reached from the Kennedy Space Center, so a launch pad on the West Coast was deemed necessary for planned military Shuttle missions. After the pad had undergone extensive modifications, the orbiter Enterprisewas used for fit checks in early 1985, and the complex was accepted into service later that year.
Space Shuttle Enterprise at SLC-6 in February 1985 (Credit: US Air Force)
The loss of Challenger in 1986, and the reviews of the Space Shuttle program that followed, saw plans for polar orbit missions canceled. At the time of the accident, the first launch from SLC-6 had been a few months away, with Discovery slated to deploy an experimental reconnaissance satellite during the STS-62-A mission. With Shuttle launches restricted to the Kennedy Space Center, SLC-6 was again placed into mothballs.
It would not be until the 1990s, when Lockheed selected SLC-6 for its Lockheed Launch Vehicle (LLV) rocket, later named Athena, that SLC-6 would finally host a launch. Four missions, two using the Athena I configuration followed by two using the Athena II configuration, were flown between August 1995 and September 1999. These launches did little to help SLC-6’s cursed reputation: the first and third missions failed to achieve orbit, while the second successfully deployed NASA’s Lewis satellite only for the spacecraft to malfunction and lose power less than three days later.
In a strange twist of fate, NROL-91 lifted off 23 years to the day after the fourth and final Athena launch from SLC-6, which successfully deployed a commercial Ikonos imaging satellite.
Athena was far smaller than the rockets that SLC-6 had been designed to serve, but Boeing’s need to find a West Coast launch site for its Delta IV rocket would bring the pad a new lease of life. The first of 10 Delta IV flights from the pad — including the NROL-91 mission — took place in June 2006 when a Delta IV Medium+(4,2) flew the NROL-22 mission, deploying a signals intelligence satellite.
A Delta IV Medium+(5,2) launches from SLC-6 in 2012 (Credit: United Launch Alliance)
The Delta IV Medium and Medium+(4,2) each made a single flight from SLC-6, while the Medium+(5,2), with a five-meter upper stage, made three flights from the pad. Including Saturday’s launch, the Delta IV Heavy configuration has used the pad five times, with all of its launches deploying Crystal satellites.
Overall, NROL-91 is the fourteenth launch to take place from SLC-6. In keeping with previous Delta IV missions, the rocket has been assigned a flight number, or Delta number, which indicates its place in the history of the Delta series of rockets. These numbers have counted — with a handful of exceptions — up from the first Thor-Delta launch in 1960. While the Delta IV is a completely different rocket even compared to the Delta II that retired a few years ago, the tradition has been maintained, and the rocket that performed Saturday’s launch is be Delta 387.
Saturday’s countdown saw the Delta IV rocket filled with cryogenic propellants while critical systems are powered up and tested as the count proceeds toward liftoff. The ignition sequence for the three RS-68A engines began seven seconds before liftoff with the starboard booster before the port and center cores ignited two seconds later. This staggered start helps mitigate the effects of hydrogen build-up around the base of the vehicle, which has scorched the rocket or set fire to insulation on previous missions.
Liftoff occurred at T0. After Delta IV cleared the tower, it began a series of pitch and yaw maneuvers to attain its planned orbit, with the first of these beginning about 10 seconds after liftoff. Flying downrange, Delta 387 throttled down its center core to its partial thrust setting. It passed through the area of maximum dynamic pressure, or Max-Q, 89.6 seconds into the mission and reached Mach 1, the speed of sound, about 1.4 seconds later.
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With the side boosters firing at full thrust and the center core operating in partial thrust mode, the port and starboard cores depleted their propellant first. As they approached burnout, they began to throttle back before shutting down at the three-minute and 56.3-second mark in the mission. The spent boosters separated 2.2 seconds later, falling away from the center core as it throttled up to full thrust.
Booster Engine Cutoff (BECO), the end of first-stage flight, occurs five minutes and 37 seconds after liftoff. Six and a half seconds after BECO, the first stage separates and the DCSS begins preparations to ignite its RL10C-2-1 engine, including deployment of the extendible nozzle. RL10 ignition occurs under 13 seconds after stage separation. 10 seconds into the burn, Delta IV’s payload fairing separates, and the NROL-91 payload is exposed to space for the first time.
With fairing separation complete, NRO missions tend to enter a news blackout, with further mission details remaining classified other than a brief press release to confirm the successful deployment of the satellite. The DCSS can be expected to continue firing its engine for about 12 minutes as it inserts the satellite directly into orbit. Spacecraft separation will occur shortly afterward, before the DCSS restarts its engine for a deorbit burn.
With Delta 387’s mission complete, only two more Delta IV missions remain to be launched. These are both slated to fly from the Cape Canaveral Space Force Station, with the NROL-68 mission slated for liftoff early next year and NROL-70 to follow in the first months of 2024. The first flight of Vulcan, ULA’s replacement for both its Delta IV and Atlas V rockets, is also currently scheduled for the first half of next year.
While these milestone launches are still some months away, ULA will be back in action on Friday with an Atlas V slated to deploy a pair of communications satellites for commercial operator SES. This is one of three Atlas V launches currently slated for the tail end of 2022, with deployment of JPSS-2, a military weather satellite, slated for the start of November and the US Space Force 51 (USSF-51) mission tracking no earlier than December.
(Lead photo: Delta IV Heavy and NROL-91 ascend toward orbit. Credit: Jack Beyer for NSF)
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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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.
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.”
