Congratulations to HEMI Fellow Susanna Thon, who has been chosen by the National Science Foundation for its prestigious CAREER Award, which recognizes early-stage scholars with high levels of promise and excellence. Thon is an assistant professor in the Department of Electrical and Computer Engineering. Prof. Thon’s research is in the field of nanomaterials engineering for optoelectronic devices, with a specific focus on renewable energy conversion and storage. Her work applies techniques from nanophotonics and scalable fabrication to produce devices and materials with novel optical and electrical functionality.
Her CAREER project, “Finite-Absorption-Bandwidth Nanomaterials for Multijunction Photovoltaics and Narrow-Band Photodetectors,” has the potential to lead to a more efficient, usable, and cost-effective way of generating solar energy.
“The basic thrust of the project is, we came up with a new way to control the color of materials,” Thon said. “We drill periodic arrays of air holes into the absorbing materials called ‘photonic crystals’, and that changes how the materials absorb light. This is a way to perform ‘color tuning,’ so it is essentially a new strategy for controlling the color in these materials.”
Thon believes that these solar cells and light sensors could eventually help create a more efficient, usable, and cost-effective way of generating solar energy. She envisions a day when the cells and sensors could be made into paints that could be used on the exteriors of homes and other buildings to capture the sun’s energy, providing heating and cooling and powering appliances inside.
She predicts that much of the work on this project will focus on achieving the level of color tuning control needed to obtain optimal results—a challenge that she feels certain that she and her excellent team at Johns Hopkins can meet.
Congratulations, Prof. Thon!
Prof. Shoji Hall from the Department of Materials Science and Engineering Joins HEMI
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.”
HEMI Fellow Muyinatu Bell Named Alfred P. Sloan Research Fellow
HEMI Fellow Muyinatu ‘Bisi’ Bell has been selected as a 2019 Alfred P. Sloan Research Fellow in Physics. Professor Bell is an assistant professor in the Department of Electrical and Computer Engineering and the Department of Biomedical Engineering. Prof. Bell leads a highly interdisciplinary research program that integrates optics, acoustics, robotics, and electronics to engineer and deploy innovative biomedical imaging systems that address unmet clinical needs. She is the director of the Photoacoustic and Ultrasonic Systems Engineering (PULSE) Lab, and the technologies developed in her lab have applications in neurosurgical navigation, cardiovascular disease, women’s health, and cancer detection and treatment. Dr. Bell is additionally interested in utilizing these novel technologies to investigate fundamental science questions surrounding the limits of laser-tissue interactions and their effect on tissue mechanical properties derived from acoustic measurements.
The Alfred P. Sloan Research Fellowship is awarded annually to young researchers based on their potential to make substantial contributions to their fields and their distinguished performance.
Congratulations to Prof. Bell on her achievement!
Two HEMI Fellows Lead Organizing Committee for 10th International Conference on Multiscale Materials Modeling
We are pleased to announce that HEMI Fellows Jaafar El- Awady (Associate Professor, Dept. of Mechanical Engineering) and Somnath Ghosh (M.G. Callas Chair Professor, Dept. of Civil Engineering) have been selected to organize the 10th International Conference on Multiscale Materials Modeling. The conference, which is the world leading forum dedicated to the dissemination of the latest development in the field of multiscale materials modeling, will be held on Oct 19-23, 2020 at the Baltimore Renaissance Harborplace hotel.
Prof. El-Awady will serve as chair of the organizing committee and Prof. Ghosh will serve as co-chair. Other members of the committee include:
Peter Chung, University of Maryland College Park
Maria Emelianenko, George Mason University
Lyle E. Levine, National Institute of Standards and Technology
We are pleased to announce that the Hopkins Extreme Materials Institute (HEMI) has been awarded an Art Works grant from the National Endowment of the Arts (NEA). This is the first grant from the NEA awarded to an organization within the Whiting School of Engineering at Johns Hopkins University. Funding will support HEMI’s collaboration with the Maryland Institute College of Art (MICA).
The HEMI/MICA Extreme Arts program is a collaboration between Johns Hopkins University and the Maryland Institute College of Art that brings faculty and students from both institutions together to explore unique perspectives on extreme events. The program aims to encourage collaboration among artists and researchers to examine data, interpret outcomes, and translate results from extreme events in new ways.
Specifically, this award will provide support to the Summer Project/Internship (for students) and the Artist/Designer in Residence position (for faculty members). These creative programs combine art, design, science, and engineering to showcase the fundamental science associated with materials and structures undergoing extreme conditions.
Participants in the program collaborate and explore solutions related to fundamental composition, materials use, and the impact of advanced technology. Artists and scientists work together to create new works of art that visually portray scientific discoveries.
The Hopkins Extreme Materials Institute is pleased to announce that the application period for the 2019 HEMI Seed Grant Program is now open. The goal of this program is to provide seed funding to advance the fundamental science associated with materials and structures under extreme conditions.
While all directions related to the HEMI Mission will be considered, some directions of particular interest include:
Structures in extreme environments, such as blast, extreme temperatures, impact/crash, natural hazards, disasters, nuclear events
Materials behavior and performance in extreme environments, such as extreme temperatures or pressures, intense radiative environments, extreme electromagnetic fields
High-power laser interactions with matter
Materials and structures applications in planetary science, space science and geophysics
Applications of 3D printing or additive manufacturing techniques to design for dynamic or impact loadings
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. Existing HEMI fellows are encouraged to apply.
The total budget request for a faculty member or team may not exceed $25,000. The project period is up to one year. HEMI leadership anticipates funding at least one seed grant award.
Obligations of Award Recipients
Award recipients will be expected to:
Complete research within one year. No-cost extensions will not be offered and funds remaining at the end of the one-year period will be returned to the Institute.
Submit a proposal for external research funding through HEMI within one year of completion of the project.
Acknowledge the support of HEMI in publications or presentations as a result of this award.
Title Page – Include proposal title, investigators, their departments and e-mail addresses.
Narrative – Not to exceed 3 pages. Must include the following:
Statement of the Problem or Area of Investigation
Project Goals and Objectives – Include the research objectives and/or technique or tool developments that will be accomplished during the HEMI Seed Grant project phase.
Future Funding and Goals – State how this project will help the proposing team attract new or additional external funding following the HEMI Seed Grant project phase. Which funding agencies and programs will be approached with future proposals?
Impact – Describe how this project will impact HEMI and/or the broader JHU research community. If the proposal involves multiple investigators, one of the investigators must be designated as the Principal Investigator, with the remaining investigators as Co-Investigators.
Budget and Budget Justification – (Budget not to exceed $25,000 for a period up to 12 months) HEMI Seed Grant Program will support all costs with the exception of faculty salary. Facilities and Administrative costs cannot be charged to this grant.
Curriculum Vitae (one or 2 pages, standard NSF or NIH formats).
Deadlines and Evaluation
The proposal deadline 5 p.m. Monday, April 1, 2019. Please email the proposal as a single PDF document and the budget/budget justification in Excel to email@example.com. The HEMI Seed Grant Program Review Committee may seek budget adjustments before making final decisions around the middle of May 2019. The Principal Investigator should ensure the proposal contains all required elements and is clearly written. Although reviewers are chosen who are familiar with some of the proposed areas of research, it is not possible to have an expert in every field represented by the proposals. Therefore, it is imperative that you make a convincing argument why this research is important in your field and should be funded at this time.
Please contact Scott McGhee (firstname.lastname@example.org) if you experience technical difficulties completing your submission or need further help in preparing your proposal.
HEMI Fellow Sarah Hörst Published in Sky and Telescope Magazine
The eight-page article details the chemical ingredients found within the each region of atmosphere of Saturn’s largest moon, Titan, and likens that complex atmospheric makeup to that of early Earth. In doing so, Hörst makes a point that, by studying Titan, we might learn enough to identify markers that will allow us to recognize habitable planets surrounding other stars.
Hörst’s primary research interest is atmospheric chemistry. She is particularly interested in the complex organic chemistry occurring in the atmosphere of Titan, but is also interested in complex organics elsewhere in the solar system and universe, whether they are produced in an atmosphere or on a surface.
Sky & Telescope is the essential guide to astronomy, showcasing each month a wide array of celestial events and astronomy news to a highly-engaged audience that includes astronomy practitioners of all levels – from novices with their first telescope, to intermediate and advanced backyard astronomers, to professionals.
Registration is now open for the 2019 Mach Conference. Sponsored by HEMI, the Mach Conference is an annual, open event that showcases the state of the art of multiscale research in materials, with an emphasis on advancing the fundamental science and engineering of materials and structures in extreme environments. The conference will be held April 3-5, 2019 in Annapolis, MD.
This year, plenary speakers include:
Air Force Research Lab
Argonne National Lab
University of Rochester
Johns Hopkins University
For more information topics being presented at the conference and to register, visit machconference.org.