Lab Report

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The Lab Report is a weekly compendium of media reports on science and technology achievements at Lawrence Livermore National Laboratory. Though the Laboratory reviews items for overall accuracy, the reporting organizations are responsible for the content in the links below.

Oct. 14, 2022

el capitan

Climate change is affecting the cooling and energy use of supercomputers like El Capitan at LLNL.

science

A climate of change for supercomputers

Managers at high-performance computing (HPC) facilities are waking up to the costly effects of climate change and the wildfires and storms it is intensifying. With their heavy demands for cooling and massive appetite for energy, HPC centers — which include both supercomputers and data centers — are vulnerable, says Natalie Bates, chair of an HPC energy efficiency working group set up by Lawrence Livermore National Laboratory (LLNL). “Weather extremes are making the design and location of supercomputers far more difficult.”

Climate change can bring not only heat, but also increased humidity, reducing the efficiency of the evaporative coolers many HPC centers rely on. The cost of such adaptations is motivating some HPC centers to migrate to cooler and drier climates, places like Canada and Finland.

But some HPC facilities find themselves stuck. The supercomputers at LLNL are used to simulate the explosions of nuclear weapons. The cost of relocating specialized personnel could be prohibitive, and LLNL’s California site is a highly secure facility, says Chief Engineer Anna-Maria Bailey. Instead, LLNL is studying the possibility of moving its computers underground. “Humidity and temperature control would be a lot easier,” she says, “like a wine cave.”

DART

The NASA DART spacecraft approaches the asteroid Dimorphos. Image courtesy of NASA.

 

A one-two punch

To test a strategy that could knock a potentially hazardous asteroid off of a collision course with Earth, NASA slammed a spacecraft into a 500-foot-wide asteroid called Dimorphos, which orbits a much larger asteroid called Didymos — and the test was literally a smashing success.

Instead of merely nudging Dimorphos onto a slightly tighter orbital path, as expected, the Double Asteroid Redirection Test (DART) delivered a cosmic face-punch that shaved 32 minutes from the moonlet’s orbit. It also turned Dimorphos into something resembling a comet: The moonlet now has a dusty debris tail some 6,000 miles long.

Megan Bruck Syal of Lawrence Livermore National Laboratory calls those images “incredible” and says that they’re helping researchers learn about how planetary impacts unfold in reality — which will inform the simulations she and her team work on.

But there’s a drawback to the DART strategy: All the dust that now swaddles the asteroid system could be dangerous to additional spacecraft. This could present a problem if one impact isn’t enough.

“In a real emergency, we might need to impart a much larger change in velocity, and the asteroid might be more massive,” Syal said. “If we needed more than one kinetic impact to successfully move an asteroid off of an Earth-impacting trajectory, a dust-filled environment may be more challenging for navigating a second impactor at the target asteroid.”

howley

LLNL’s Kirsten Howley is a planetary defender.

ary news

Life isn’t always like the movies

Not that an asteroid couldn’t slam into Earth, mind you. Asteroids — mostly tiny ones — pass by our planet virtually every second. But the people charged with stopping the big ones aren’t reaching for their spacesuits with mere hours to spare. They also aren’t all men.

"I would say the number one question I get when I tell people what I work on, is ‘Oh, like ‘Armageddon?' And it’s nothing like ‘Armageddon,’” says Lawrence Livermore National Lab physicist Kirsten Howley, whose day job includes defending our planet from asteroids.

Howley doesn’t have an orange jumpsuit at hand, but her job is serious business. She and her team of planetary defenders specialize in how we might deflect an asteroid that poses a threat to Earth. Like Bennu.

Bennu, weighing more than 78 billion kilograms, is an ancient asteroid currently orbiting the sun on a path that brings it close to Earth. It has a 1-in-2,700 chance of colliding, albeit not until 2185.

If this were a movie, Howley and her team would be on the poster, among the people tasked with saving the Earth. But Oakland native Howley, who chased her childhood passion for the stars from community college to UC Berkeley to UC Santa Cruz, where she became the first person in her family to earn a Ph.D., is not sitting around waiting to jump onto a rocket at a second’s notice.

Because she doesn’t have to. Her arsenal against Earth-killing asteroids includes physics and math.

magnetism

Earth is surrounded by a giant magnetic bubble called the magnetosphere, which is part of a dynamic, interconnected system that responds to solar, planetary and interstellar conditions. Photo courtesy of NASA.

Laser magnetism goes extreme

There are few places on Earth where conditions get as extreme as they do at the National Ignition Facility. At its heart, 192 lasers are trained on a gold cylinder roughly the size of an AA battery. As the beams converge, the temperature in the test chamber leaps to 100 million degrees Celsius, hotter than the center of the sun.

The facility was built to investigate the possibility of harnessing nuclear fusion, which promises unlimited clean energy. But earlier this year, researchers announced that its powerful lasers have also been directed at a different kind of big question — what shaped the universe?

For decades, it has been thought that only gravity has what it takes to sculpt such wonders. Now, hot on the heels of a slew of intriguing galactic observations, laser-fired experiments are throwing up hints that we may have wrongly dismissed the influence of another force.

Magnetism has always been considered too weak to be a cosmic sculptor. But those behind the latest results claim that in the white heat of the test chamber, they have caught a glimpse of how this forgotten force can be turbocharged. If so, we might have to find a new place for magnetism, alongside gravity, in our picture of how the cosmos came to look the way it does.

earth model

A simulation of the planet from the DOE Energy Exascale Earth System Model, one of the large-scale models incorporated in the Earth System Grid Federation led by DOE’s Oak Ridge, Argonne and Lawrence Livermore national laboratories. Image courtesy of the Department of Energy.

Better future climate predictions

The Earth System Grid Federation (ESGF), a multi-agency initiative that gathers and distributes data for top-tier projections of the Earth’s climate, is preparing a series of upgrades that will make using the data easier and faster while improving how the information is curated.

The federation, led by the Department of Energy’s Oak Ridge National Laboratory in collaboration with Argonne and Lawrence Livermore national laboratories, is integral to some of the most important, impactful and widely respected projections of the Earth’s future climate: those made by scientists working with the Coupled Model Intercomparison Projects for the World Climate Research Programme.

A key ESGF mission is to support the data needs of scientists who prepare the United Nations Intergovernmental Panel on Climate Change (IPCC)’s comprehensive climate assessments released every six to seven years. ESGF data underpin IPCC landmark reports such as the recent Sixth Assessment Report, AR6, and its working group findings. The data also informs IPCC special reports focused on climate vulnerabilities, adaptation scenarios and mitigation strategies.

Lawrence Livermore brings a wealth of high-performance computing and data center expertise and capabilities, creative technologies and software solutions to ESGF, plus its experience as the initial lead of the ESGF.

“The upgrades will make it easier and faster for users to access the data that can help us better understand what climate will look like in the future,” said Sasha Ames, LLNL lead for the federation.