LAB REPORT

Hundreds of new Caltech students streamed across Beckman Mall Friday morning, passing beneath an arch of orange, white and turquoise balloons before filing into Beckman Auditorium for a formal welcome to one of the world’s most demanding scientific communities.

Waiting inside was something considerably smaller.

Held aloft in a clear cylindrical display was a tiny fusion target — the kind of object that helped scientists at Lawrence Livermore National Laboratory achieve what had eluded researchers for generations: fusion ignition.

“This little target,” Caltech Class of 1985 alumna Tammy Ma told the students, holding it up. “This is what we turn into a star.” It was an apt centerpiece for Caltech’s 2026 Convocation, a ceremony about beginnings, difficult questions and what can happen when very small things are pushed to extraordinary limits.

When NASA's OSIRIS-REx capsule landed in the Utah desert on September 24, 2023, it carried largest sample from an asteroid returned to Earth since the Apollo lunar missions — 121.6 grams of material scraped from the surface of asteroid Bennu. Three years later, a half gram of that material has produced a finding that recasts one of the most fundamental questions in planetary science: where do Earth's water and organic molecules come from? The answer, a new study from ETH Zurich reports, may begin with Jupiter.

The study shows that Bennu did not form in the distant outer solar system as scientists had long assumed.

Bennu's isotopic fingerprint for iron and titanium matches neither the inner solar system's rocky, sun-baked material nor the icy, organic-rich material typical of bodies that formed beyond Jupiter. Instead, it matched something in between — a hybrid composition characteristic of both regions simultaneously. A Lawrence Livermore companion analysis confirms the ETH Zurich results, using a separate sub-sample of the same Bennu material.

Researchers at Lawrence Livermore National Laboratory (LLNL) have developed a 3D printed solid-state bioreactor that converts waste methane into succinate, a chemical used to make polymers, stabilize drugs and add flavor to food.

According to the team, the system performed more than 10 times better than conventional liquid-state systems while consuming less power.

Methane produced at landfills and wastewater treatment plants is often burned, and its energy value is lost. The researchers built the reactor to recover that gas as a fuel, chemical feedstock or bioproduct.

“Bioproduction using poorly soluble gases has long been limited by slow mass transfer and low efficiency because conventional liquid-phase bioreactors are not well suited for gas fermentation,” said Fang Qian, a scientist at LLNL and corresponding author of the study.

The team printed thin lattice scaffolds and filled their walls with a hydrogel containing methanotrophs, bacteria that naturally consume methane.

Tropical cyclones, also known as hurricanes or typhoons, are some of the most powerful weather events on the planet, impacting millions when they make landfall. Predicting them saves lives, but takes an enormous amount of math, including fluid dynamics calculations — exactly the types of simulations GPUs excel at producing. Researchers from the Naval Postgraduate School (NPS) have proven their model, using GPUs, is five times faster than the CPU model by using U.S. National Science Foundation ACCESS allocations on NCSA’s Delta supercomputer.

Soonpil Kang was a postdoctoral researcher at the NPS working with Frank Giraldo, a distinguished professor in the Department of Applied Mathematics at NPS, when this research was conducted.

“We focused on how to efficiently simulate a large-scale, realistic tropical cyclone by leveraging GPU capabilities,” said Kang, currently a postdoctoral researcher at Lawrence Livermore National Laboratory (LLNL).

A multi-institutional team from the U.S. Department of Energy’s DIII-D National Fusion Facility recently won the John Dawson Award for Excellence in Plasma Physics Research from the American Physical Society for substantially advancing the negative triangularity approach for fusion.

Tokamaks, donut-shaped devices that contain 100,000,000 degree Celsius plasmas with magnetic fields to drive fusion reactions, are one of the leading designs for commercial fusion pilot plants. Most development of operational approaches for tokamaks has focused on positive triangularity, a D-shaped plasma with the curve facing the outer edge of the device.

An alternative solution is to move away from the positive triangularity shape altogether, operating the plasma in a reverse-D shape called negative triangularity (NT).

Beginning in 2022, the team embarked on a dedicated diverted NT campaign. Filippo Scotti, research scientist at Lawrence Livermore National Laboratory, worked with the General Atomics Engineering team for DIII-D to replace the standard tile armor in the lower divertor with specialized tiles designed for NT operation.

The Lab Report will take a break next week and return on Oct. 16 with a new look and a biweekly cadence. The updated newsletter will include curated media clips, a photo of the week, episodes of the Big Idea Lab podcast, LLNL-produced stories and social media highlights.