HEMI Fellows awarded Space@Hopkins seed grants

Paulette Clancy, department head and professor in Chemical and Biomolecular Engineering at the Whiting School of Engineering, and Sarah Hörst, associate professor in the Department of Earth and Planetary Sciences at the Krieger School of Arts and Sciences, have been awarded the 2022 Space@Hopkins seed grants.  

Space@Hopkins brings together researchers from across Johns Hopkins University divisions, departments, and collaborative institutes to advance civilian space research. The grants are intended  to enable Johns Hopkins researchers to test and develop new ideas that enhance their ability to obtain external funding.   

Hörst is a co-investigator on the seed grant project, “Electrification of Titan and Sand Materials” seed grant. Clancy’s project is titled, “Sheltering Life on Titan and Enceluadus.”   

MICA extreme arts interns present final projects

Interns in the Extreme Arts program, a collaboration between HEMI and Maryland Institute College of Art, presented their final projects recently to an audience including HEMI mentors, staff, and students.

Started in 2015, the HEMI/MICA Extreme Arts internship program brings students from MICA to HEMI to translate results of HEMI’s research on extreme events in creative and visual ways.

Riley Cox, MICA student majoring in fibers, interned with Rebecca Schulman, an associate professor in the Whiting School of Engineering’s Department of Chemical and Biomolecular Engineering. Cox experiments with weaving structures that contain LED matrices and can be coded to light up portions of cloth in desired patterns. Her goal is to create responsive, smart textiles that could be programmed to generate patterns, both through the physical process of weaving and through integrated technology.

During her internship, Cox says she was “inspired by Professor Schulman’s use of synthetic DNA computing circuits as a way to generate patterned responses.”

In Schulman’s research, chemical patterns act as a blueprint, defining the growth of cells. The process of weaving can function in a similar way, relying on patterns embedded in the order and placement of threads to create an output of different structures of cloth, according to Cox.

“The loom has historically been considered the precursor to modern computing,” said Cox,  whose project explores this relationship between technology and handcraft.

In tackling her project, she used digital drafting software which allowed her to experiment with patterns that could be generated within the threading process.

Fibers work by Riley Cox

Fibers work by Riley Cox

Candice EH Cramer, a MICA student majoring in multidisciplinary art, says, “The most resilient of things on Earth are what comprises the planet: minerals. Some of these minerals, like zircon and garnet extracted today, could share evidence of evolution during the earliest part of Earth’s history.”

Cramer interned at HEMI with Emmy Smith, an assistant professor in the Krieger School of Arts and Science’s Department of Earth and Planetary Sciences. Cramer said that through Smith’s work, she was able to “glean whispers of Precambrian life recorded in sedimentology, which endures beyond carbon dating by using uranium lead dating.” Through observing rocks extracted for their zircons, searching for sulfur as metabolism markers in marine sediments, and witnessing garnets prepared for spectrometry, she said she “gained a fondness” for minerals for their intrinsic value and their innate storytelling.

“As we face an age on Earth that is being shaped in front of our eyes by humans to the detriment of the environment, I wonder if these minerals can offer us wisdom by examining and replicating their forms through drawing,” said Cramer.

She is also inspecting minerals found in paint pigments to ponder upon the sustainability of the painting practice.

The event completes the eighth consecutive year of the Extreme Arts program which is a collaborative program between HEMI at Johns Hopkins University and the Maryland Institute College of Art.

Multidisciplinary Art by Candice EH Cramer

Resilient Shard
(Snowball Earth)
by Candice EH Cramer

Breaking Up is Hard to Do: Asteroids Are Stronger, Harder to Destroy Than Previously Thought

A frame-by-frame showing how gravity causes asteroid fragments to reaccumulate in the hours following impact.

A frame-by-frame showing how gravity causes asteroid fragments to reaccumulate in the hours following impact. (Credit: Charles El Mir / Johns Hopkins University)

A popular theme in the movies is that of an incoming asteroid that could extinguish life on the planet, and our heroes are launched into space to blow it up. But incoming asteroids may be harder to break than scientists previously thought, finds a Johns Hopkins study that used a new understanding of rock fracture and a new computer modeling method to simulate asteroid collisions.

The findings, to be published in the March 15 print issue of Icarus, can aid in the creation of asteroid impact and deflection strategies, increase understanding of solar system formation, and help design asteroid mining efforts.

“We used to believe that the larger the object, the more easily it would break, because bigger objects are more likely to have flaws. Our findings, however, show that asteroids are stronger than we used to think and require more energy to be completely shattered,” says Charles El Mir, a recent PhD graduate from the Johns Hopkins University’s Department of Mechanical Engineering and the paper’s first author.

Researchers understand physical materials like rocks at a laboratory scale (about the size of your fist), but it has been difficult to translate this understanding to city-size objects like asteroids. In the early 2000s, a different research team created a computer model into which they input various factors such as mass, temperature, and material brittleness, and simulated an asteroid about a kilometer in diameter striking head-on into a 25-kilometer diameter target asteroid at an impact velocity of five kilometers per second. Their results suggested that the target asteroid would be completely destroyed by the impact.

In the new study, El Mir and his colleagues, K.T. Ramesh, director of the Hopkins Extreme Materials Institute and Derek Richardson, professor of astronomy at the University of Maryland, entered the same scenario into a new computer model called the Tonge-Ramesh model, which accounts for the more detailed, smaller-scale processes that occur during an asteroid collision. Previous models did not properly account for the limited speed of cracks in the asteroids.

“Our question was, how much energy does it take to actually destroy an asteroid and break it into pieces?” says El Mir.

The simulation was separated into two phases: a short-timescale fragmentation phase and a long-timescale gravitational reaccumulation phase. The first phase considered the processes that begin immediately after an asteroid is hit, processes that occur within fractions of a second. The second, long-timescale phase considers the effect of gravity on the pieces that fly off the asteroid’s surface after the impact, with gravitational reaccumulation occurring over many hours after impact.

In the first phase, after the asteroid was hit, millions of cracks formed and rippled throughout the asteroid, parts of the asteroid flowed like sand, and a crater was created. This phase of the model examined the individual cracks and predicted overall patterns of how those cracks propagate. The new model showed that the entire asteroid is not broken by the impact, unlike what was previously thought. Instead, the impacted asteroid had a large damaged core that then exerted a strong gravitational pull on the fragments in the second phase of the simulation.

 

The research team found that the end result of the impact was not just a “rubble pile” – a collection of weak fragments loosely held together by gravity. Instead, the impacted asteroid retained significant strength because it had not cracked completely, indicating that more energy would be needed to destroy asteroids. Meanwhile, the damaged fragments were now redistributed over the large core, providing guidance to those who might want to mine asteroids during future space ventures.

“It may sound like science fiction but a great deal of research considers asteroid collisions. For example, if there’s an asteroid coming at earth, are we better off breaking it into small pieces, or nudging it to go a different direction? And if the latter, how much force should we hit it with to move it away without causing it to break? These are actual questions under consideration,” adds El Mir.

“We are impacted fairly often by small asteroids, such as in the Chelyabinsk event a few years ago,” says Ramesh. “It is only a matter of time before these questions go from being academic to defining our response to a major threat. We need to have a good idea of what we should do when that time comes – and scientific efforts like this one are critical to help us make those decisions.”

Prof. June Wicks Selected as HEMI Seed Grant Recipient

Congratulations to the recipient of the 2018 HEMI Seed Grant, Prof. June Wicks!

Professor Wicks is an Assistant Professor in the Earth and Planetary Sciences Department. Research interests include planetary interiors and evolution; building equation of state and phase diagram models of matter at extreme conditions; kinetics of phase transitions at extreme conditions. In addition to funding her project “Bridging Accessible Strain Rates in the Lab to Recreate Meteorite Impacts”, she will be using the grant to expand the capabilities of her research group.

The HEMI seed grants are given each year to fund research in fundamental science associated with materials and structures under extreme conditions. All faculty and researchers at the Johns Hopkins University, as well as Applied Physics Laboratory (APL) Staff, who can serve as Principal and Co-Investigators are eligible to apply. Learn more about the program here https://hemi.jhu.edu/hemi-seed-grant.