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Never Tell Me the Odds: NASA’s Lucy To Fly Past Thousands of Objects for Earth Gravity Assist

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On October 16, 2022, NASA’s Lucy spacecraft will fly by the Earth for the first of three gravity assists. During the maneuver, Lucy will pass within 219 miles of the planet (lower than the International Space Station) and will fly through a cloud of over 6,200 Earth-orbiting satellites. This data visualization depicts Lucy’s trajectory through the satellite swarm. Credit: NASA’s Scientific Visualization Studio

 

Mission engineers will continually track <span class=”glossaryLink” aria-describedby=”tt” data-cmtooltip=”

NASA
Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. Its vision is &quot;To discover and expand knowledge for the benefit of humanity.&quot; Its core values are &quot;safety, integrity, teamwork, excellence, and inclusion.&quot;

” data-gt-translate-attributes=”[“attribute”:”data-cmtooltip”, “format”:”html”]”>NASA’s Lucy spacecraft as it prepares to swing by Earth on October 16 for a gravity assist. This will allow it to use this planet’s gravity to gain some of the orbital energy and set itself on a course toward the <span class=”glossaryLink” aria-describedby=”tt” data-cmtooltip=”

Jupiter
Jupiter is the largest planet in the solar system and the fifth planet from the sun. It is a gas giant with a mass greater then all of the other planets combined. Its name comes from the Roman god Jupiter.

” data-gt-translate-attributes=”[“attribute”:”data-cmtooltip”, “format”:”html”]”>Jupiter Trojan asteroids.

However, that’s not all the engineers will be closely tracking. They will have to keep a look out for more than 47,000 satellites, debris, and other objects circling our planet. A greater than 1-10,000 chance that Lucy will collide with one of these objects, and mission engineers will be required to slightly adjust the spacecraft’s trajectory.

 

Although an adjustment is unlikely, and collisions are rare, NASA experts say the chances are increasing as the number of objects in Earth’s orbit grows.

The International Space Station (ISS), for example, has maneuvered out of the way of space debris 31 times since 1999, including three times since 2020.

NASA’s Lucy Earth

On October 16, 2022, Lucy will fly by the Earth like a partner in a swing dance, boosting its speed and elongating its orbit around the Sun. At 7:04 am, Eastern Time, Lucy will make its closest approach at just 219 miles above the planet: lower than the International Space Station. This exceptionally close shave will increase its velocity by four-and-a-half miles per second, setting Lucy on track to gain even more speed when it returns to Earth for its second gravity assist in December 2024. Credit: NASA’s Goddard Space Flight Center

 

“Low-Earth orbit is getting more crowded, so that has to be part of the consideration nowadays, especially for missions that fly low, like Lucy,” said Dr. Dolan Highsmith. He is chief engineer for the group that determines the probabilities of collisions between NASA’s robotic spacecraft and Earth-orbiting objects, the Conjunction Assessment Risk Analysis group at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. NASA’s Johnson Space Center in Houston does the same for crewed spacecraft, including the space station.

Launched a year ago, on October 16, 2021, Lucy is on a 12-year-journey to study multiple Trojan asteroids up close. Discovered by German astrophotographer Max Wolf in February 1906, the Trojan asteroids are trapped in orbits around the Sun at the same distance as Jupiter. Lucy will be the first spacecraft to visit these remnants from the early solar system, helping scientists hone their theories on how the planets formed 4.5 billion years ago and why they ended up in their current configuration.

But Lucy has a long way to go before it arrives at the Trojans in 2027. The upcoming gravity assist is one of three the spacecraft will rely on to catapult itself to its deep-space targets.

[embedded content]
On October 16, 2022, NASA’s Lucy spacecraft will fly by the Earth for the first of three gravity assists. During the maneuver, Lucy will pass within 219 miles of the planet (lower than the International Space Station) and will fly through a cloud of over 6,200 Earth-orbiting satellites. This data visualization depicts Lucy’s trajectory through the satellite swarm. Credit: NASA’s Scientific Visualization Studio

 

When Lucy comes nearest to Earth for its first gravity assist it will cruise 220 miles (350 km) above the surface. That’s lower than the altitude of the space station and low enough that the spacecraft will be visible with the naked eye from western Australia for a few minutes starting at 6:55 p.m. local time (10:55 <span class=”glossaryLink” aria-describedby=”tt” data-cmtooltip=”

UTC
Coordinated Universal Time or Universal Time Coordinated (UTC) is the primary time standard by which the world regulates clocks and time.&nbsp;Prior to 1972, this time was called Greenwich Mean Time (GMT) and is also known as &quot;Z time&quot; or &quot;Zulu Time.&quot; &nbsp;It is, within about 1 second, mean solar time at 0° longitude.

” data-gt-translate-attributes=”[“attribute”:”data-cmtooltip”, “format”:”html”]”>UTC). On its way down, Lucy will fly through the most crowded layer of Earth’s orbit, which is monitored by the U.S. Space Force’s 18th Space Control Squadron. The squadron helps NASA identify close approaches.

Engineers began collision analysis for Lucy a week before the spacecraft’s Earth approach. Starting the process any earlier would render collision predictions futile, Highsmith said: “The further you’re predicting into the future, the more uncertain you are about where an object is going to be.”

Lucy Trojan Asteroid Mission

Lucy will explore the Jupiter Trojan asteroids – thought to be “fossils of planet formation.” Credit: NASA’s Goddard Space Flight Center

Determining the positions of spacecraft, plus orbiting satellites and debris, is challenging, particularly when trying to anticipate the future. Largely that’s because the Sun plays a major role in pulling or pushing objects around, and future solar activity is hard to predict. For example, the Sun’s activity — how much <span class=”glossaryLink” aria-describedby=”tt” data-cmtooltip=”

plasma
Plasma is one of the four fundamental states of matter, along with solid, liquid, and gas. It is an ionized gas consisting of positive ions and free electrons. It was first described by chemist Irving Langmuir in the 1920s.

” data-gt-translate-attributes=”[“attribute”:”data-cmtooltip”, “format”:”html”]”>plasma and radiation it shoots out — affects atmosphere density, and thus how much friction will tug on a spacecraft and slow it down.

 

So the closer the collision assessment is to the Earth flyby time, the better. NASA sends Lucy’s whereabouts to the Space Force squadron daily. If the squadron determines that Lucy could intersect with something, Highsmith’s group will calculate the probability of a collision and work with the mission team to move the spacecraft, if necessary.

[embedded content]
Ride-along view of Lucy’s first Earth gravity assist (EGA). The camera follows Lucy as the spacecraft approaches the sunlit side of Earth before crossing into Earth’s shadow as it slingshots around the planet. This is a slower version of the full ride along view above, focusing on the approach. Credit: NASA’s Scientific Visualization Studio

“With such a high-value mission, you really need to make sure that you have the capability, in case it’s a bad day, to get out of the way,” Highsmith said.

Lucy navigation engineers have two maneuver options ready in case the spacecraft needs to avoid an object. Both maneuvers require engine burns to speed up the spacecraft, which is traveling about 8 miles (12 km) per second. Each maneuver can move Lucy’s closest approach to Earth up by 2 seconds or 4 seconds, respectively.

 

“That’s enough to avoid any one thing that could be in the way,” said Kevin E. Berry, Lucy’s flight dynamics team lead from NASA Goddard.

[embedded content]

Hal Levison of Southwest Research Institute (SwRI), in the Boulder, Colorado, office, is the principal investigator. SwRI, headquartered in San Antonio, also leads the science team and the mission’s science observation planning and data processing. NASA Goddard provides overall mission management, systems engineering, and the safety and mission assurance for Lucy. Lockheed Martin Space in Littleton, Colorado, built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace in Simi Valley, California, are responsible for navigating the Lucy spacecraft. Lucy is the 13th mission in NASA’s Discovery Program, which is managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama.

 

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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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