A Universe of Plasma: How one Scientist Connects his World from Satellites to Cells.
- Aidan Schurr
- Jan 20
- 8 min read
“You can't connect the dots looking forward; you can only connect them looking backwards. So you have to trust that the dots will somehow connect in your future” - Steve Jobs.
Every scientist begins their journey with a general sense of direction, attempting to become an expert in one field. However, it is not always obvious what path your interests will lead you down. In many cases, this induces anxiety for those pursuing a career in STEM, as we are told to “figure out what you want to do” for the rest of your life. Sitting down with Professor Michael Keidar, we will trace the steps of his illustrious career backwards, learning about how he tackled these exact questions that landed him to work in applying his knowledge across diverse fields such as brain tumor therapy, satellite design, and electromagnetic-induced drug delivery.
Plasma and Purpose: The Multifaceted Journey of Dr. Michael Keidar
Who:
Professor Michael Keidar is The James A. Clark Professor of Mechanical Engineering at George Washington University. His main research interests focus on designing optimized propulsion technology for spacecrafts such as satellites, and developing nanoscale plasma technology. Despite this, some of his most well-known work was his application of cold plasmas in cancer therapy, demonstrating his ability to apply his work across fields. Professor Keidar completed his PhD at Tel Aviv University and Postdoc appointments at UC Berkeley and Cornell University. He recently received a DARPA grant to develop low flying satellites powered by atmospheric pressure differences.
Why:
Many believe a scientific career is limited to either purely basic research or theoretical expertise. However, Dr. Keidar demonstrates that one can be a trailblazer in both fundamental research and make an impact on the lives of others. Furthermore, his career showcases the importance of obtaining valuable skills that can be applied across fields, unlocking the potential to maintain interdisciplinary interests. Many of us can benefit from hearing the story of such an impactful scientist, who continues to trailblaze almost 30 years after he began.
Understanding the Fourth State of Matter: Plasma’s Role in the Universe
Micropropulsion of Satellites. Cancer Therapy. Electromagnetic Induced Cellular Responses.
To the naked eye, these are wildly different fields, each separated by vast oceans of knowledge. However, Michael Keidar sees them all connected through the unifying state of the universe: plasma.
The three states of matter — solid, liquid, and gas — are commonly taught in Middle School science. However, the state that makes up over 99% of the universe, plasma, is almost always forgotten.
Plasma is likely omitted from the standard middle school curriculum because it requires a deeper understanding of electromagnetic forces and ionization, both of which are taught in High School. Moving forward in our understanding of the world, we begin to learn about plasma, the state of matter that makes up over 99% of the universe. Everything from lightning to stars to fluorescent light bulbs is made of plasma.
To create plasma, a gas is superheated, leading many of the electrons to be stripped away. This induces an electrical imbalance on the gas particles that generate what we call “plasma.” Thus, plasma consists of highly energized particles, producing electrically conductive material that interacts strongly with the electromagnetic field.
And here lies the secret to the story of plasmas. The interaction of the highly charged species of particles in plasmas within the electromagnetic field induces an electromagnetic interaction. The fundamental ideas of plasma are the dots that Keidar connects throughout his career.
Lightning Strikes: How Plasma Found Michael Keidar
Growing up in the USSR during the Cold War, Keidar was brought up in the thick of the Space Age. Naturally, Keidar began to ask questions about the fundamentals of spacecraft propulsion from a young age. From these interests, he completed his undergraduate degree in Aerospace Engineering with a focus on electrical space propulsion from the Kharkov Aviation Institute. His education focused primarily on practical applications, centering on designing more propulsion systems for efficient satellites to save energy and conserve space.
“At that time, [it] was considered quite advanced,” Keidar said. “The idea was to use electricity instead of heating fuel and oxidizer, you can reach much higher velocities and use less… but there are downsides as electricity is limited on satellites.”
Here, at the end of his undergraduate degree, he saw the first possibilities of plasma, beginning to study more fundamental questions dealing with the nature of plasmas as opposed to their application. After completing his PhD in Plasma Engineering at Tel Aviv University, Keidar could now focus more on using the natural properties of plasma to produce advancements. Due to the highly charged and extremely conductive fundamental properties of plasmas, Keidar produced work that harnessed these properties to propel spacecraft through the repulsive properties of the electromagnetic field..
The shift toward more plasma-centered research was furthered by two postdoc appointments at UC Berkeley and Cornell research labs. Now, after almost a decade of research under his belt and a transition toward plasma research, Keidar has amassed unparalleled expertise in the field. Yet, his desire to make advancements in applying these technologies never went away.
Pursuing a Professorship at GW, Keidar simultaneously opened a research lab that married his interests in plasma research and aerospace propulsion. The Micropropulsion and Nanoparticles Lab helped focus his interests on extremely small spacecraft and plasma-based nanoparticles. Despite this, Keidar could not expect where his career would turn from here…
Cold Plasmas: A Paradigm Shift
Almost accidentally, Professor Keidar entered the Biomedical field in a momentous fashion. At the time, in the late 2010s, there was no Department of Biomedical Engineering at GW, yet there was a Biomedical Institute that funded several projects in other departments for biomedical research. Despite being housed in the Mechanical Engineering Department, Keidar sought projects that had biomedical applications for his plasma research. Here, he envisioned working with his “cold” plasmas.
“We started to develop what we call cold plasmas. Typical plasma in a lab is millions of degrees Celsius; the trick here is to apply a very strong electromagnetic field, which creates positive ions extremely quickly, allowing for an energetic, room temperature plasma.”
The resulting cold plasma is a cocktail of reactive species, oxygen, nitrogen, and ozone compounds, all present in both the human body and the atmosphere. The creation of these charged species acts as a reservoir that can be called, if necessary, to correct some biological processes. In short, with a cold plasma induced in a cell, these necessary compounds can be delivered without harming the cell.
The possibility to induce the creation of these species then affected the pattern of cell migration. “We alter the migration of cells and thought, maybe this would be good to slow down the migration of cells from tumor areas.” Through experiments at Johns Hopkins University, plasma therapy was found to selectively kill cancerous cells. This discovery led to the FDA approval of Canady Helios Cold Plasma to develop plasma therapy into a commercially viable product.
To this day, his plasma medicine research is still his most cited paper, although this remains outside of his “Foundational Work”. Despite this, the dots still connect, as all of this was possible from his understanding of Plasma Fundamentals.
The Marriage of Propulsion and Therapy
After his stint focusing on biomedical applications, Keidar returned to the questions that had begun his career: Can we fly satellites low enough in orbit that the air they collect can be converted to plasma and used to cancel out the drag produced by the spacecraft? Typically, with plasma-induced propulsion, ions are expelled and induce a “jet effect”. Issues arise when the positive ions are ejected, as they take the positive charge and leave the satellite negatively charged. On large scales, such as a satellite, this induces such a large negative electrical differential that the positively charged particles are attracted back to the spacecraft, inhibiting the electromagnetic force.
In order to answer this question, Keidar had to look back on his fundamental understanding of plasma physics and atmospheric chemical interactions. Put simply, how can oxygen and nitrogen in the atmosphere help to solve this problem? One effect of oxygen at low energy is that electrons actually attach to oxygen atoms more strongly than the positively charged ions from the spacecraft. Thus, an expulsion of oxygen could potentially counterbalance the ionic buildup of negative charges.
To test this hypothesis, Keidar needed to call on his previous biomedical work, which involved understanding the same interactions but on a cellular level. When developing the cold plasma cancer therapy research, the interactions between all the induced chemical species from the plasma needed to be monitored to determine the side effects of the treatment. Now, with this database of chemical interactions, it was possible for Keidar to predict the outcomes of his plasma’s effects more precisely. These same species are the ones that interact in the Atmosphere.
Once again, Keidar proves how the dots continue to connect long after the dots begin to appear.
Push the Needle Forward: Dr. Keidar’s Wisdom for Aspiring Scientists
When asked to reflect on his career and any advice he’d give to aspiring scientists, Keidar focused on watering those curious questions that every scientist needs to have in order to succeed.
“It’s hard to develop your direction when you chase the inconsistent interests of others, but you must resist that urge.”
Now, at this stage in his career, as a Professor in the capital of the United States, he often finds the interests of others clouding his line of sight. NIH, NSF, DOE, DARPA, DOD, all government agencies that Michael Keidar has worked with to help advance the questions he chooses to attack. Although these groups are important in setting a trend in research, Keidar emphasizes the even greater importance of pursuing meaningful research that is both novel and applicable to real problems faced in these fields
“Above all I recommend that people do not chase. Push the needle toward what you believe in”
For aspiring scientists, becoming an “expert” in a field is an honor and a dream. To be able to help push forward your tiny corner of STEM is the goal of all professional scientists. At every stage of his career, Dr Keidar pursued what he believed was going to advance the lives of others. His career has touched fields from brain tumors to satellite development. It begins to show the ever-growing collaborative nature of science, as not distinct disciplines but an orchestra of moving parts. To be able to say you push forward multiple fields, now this is the mark of a very special scientist.
The more we study extraordinary people, the more we learn about the importance of connecting the dots. For Jobs, this was merging calligraphy into the design of his first Macintosh Computer. For Professor Michael Keidar, it is exploring the secrets of the fourth state of matter in the universe: plasma.
My Own Reflections & Takeaways
To me- an aspiring scientist with the expectations of a scientific career placed before me- I was moved by Professor Keidar’s story of creativity and curiosity across the numerous areas of research he has entered. I believe that in the face of an ever increasingly dynamic world, it is important to build skills that can transcend the static barriers of strict categories and instead pursue fundamental interests that can open the doors in even more ways.
For each of us, it is important to take a deep breath and follow our interests, constantly pushing to understand not just the surface, but the underlying mechanisms. Through understanding the core of any field, we can each unlock abilities to further our understanding of the applications of fundamental sciences and their impact on our society. I began with the Steve Jobs quote, legendarily spoken at the Stanford Commencement in 2005, and I believe the end of that quote helps to encapsulate this story as well:
“Because believing that the dots will connect down the road will give you the confidence to follow your heart, even when it leads you off the well-worn path.”
To all the students currently trying to figure out what field they want to enter, what PhD program to enter, what research lab they want to join, or even what classes they want to take next semester, remember to follow your interests and think of the bigger picture. Nurture your curiosity and water your creativity, and remember that when in doubt, have faith that your dots will connect, even when you can’t see how.
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