When, Not If
Is there extraterrestrial life in our solar system? Desmond Kaplan – who works across several analytical projects at NASA – is willing to place a wager
Jessica Allerton | | 6 min read | Interview
Detecting extraterrestrial life in our solar system was once reserved for the pages of science fiction novels, but thanks to the remarkable advancements in analytical instruments, we may be at the precipice of huge discoveries.
In part one of our series featuring the analytical scientists involved in developing the methods required to make the crucial measurements in far from ideal conditions, we spoke with NASA Astrobiologist Melissa Trainer about the DraMs mission to Titan.
Here, we speak with Desmond Kaplan – Consultant Research and Development Scientist who works across multiple projects at NASA – about the role of mass spec in detecting life on moons within our solar system.
How did you get into this area of research – what is it about space exploration that excites you?
I grew up in Maryland spending a large portion of my childhood around the Goddard Space Flight Center at NASA and going to space camps. While I never envisioned myself working at Goddard, it just happened to be a natural evolution in my life. The golden age of space projects in the 1980s fascinated me greatly; from traveling to the moon, to watching ring structures form into biospheres – I couldn't keep my eyes off it!
From this, I went into analytical science and worked in industry getting involved with mass spectrometry and instrument development. An opportunity presented itself to work on mass spec for spaceflight missions, which I enthusiastically accepted. Since being at Goddard, I’ve been a part of some really exciting missions, hoping to discover life in a frozen world – seeing if a biological environment could exist in the ocean beneath the thick ice crust on Europa or Enceladus.
What is the Goddard nESI (GESI) System?
GESI is a capillary electrophoresis mass spectrometry interface which takes ions from the liquid to the gas phase through nano electrospray ionization (nano-ESI). This, in turn, is tied to Ocean Worlds Science Exploration and Analogs (OSEAN) – a capillary electrophoresis system. The team at OSEAN are responsible for pioneering the miniaturization and portability of the system, and we take care of the interface and mass spec.
With this system, the aim is to look at ocean worlds and icy environments at an amino acid level. The best way to deal with ice is by melting it down and to use nano-ESI – because gas chromatography doesn’t work to its best abilities on polar compounds. ESI’s strength is in polar compounds, which is why developing this system for space provides the strongest applications. In simple terms, GESI is a ESI system with an atmospheric interface consisting of a standard setup – ion funnel and ion multipole into a small linear ion trap. This is the same design concept that’s used on the Dragonfly system (DraMs) to Titan, the Rosalind Franklin (ExoMars) Rover, and the Exo Mars Organic Molecular Analyzer (MoMA) instrument.
At the core of GESI is multidisciplinary collaboration – which goes for other systems and projects across Goddard and NASA. When you see the group sizes for these projects, you can see it really does take a village to get things done.
Could you tell us more about your current projects – what is your role within the team?
There are two other projects I’m currently working on – the Exo Mars Organic Molecular Analyzer (MOMA) and the EMILI instrumentation project. The goal of MOMA is to detect and identify organic material below the surface of Mars. It is the largest instrument on the Rosalind Franklin (ExoMars) Rover that is due to launch in the coming years. I’ve helped to develop the isolation and tandem mass spectrometry (MSMS) routines that are critical for determining the structure and organic nature of molecules.
Meanwhile, EMILI is designed to analyze Europa ice samples coming from a lander. The system uses a capillary electrophoresis electrospray ionization instrument and an electron impact ionization gas chromatography instrument – creating ions that will go into the ion trap of the mass spectrometer. I’ve been responsible for designing and implementing the ion optics for the electrospray ionization source for the instrument.
The challenge of taking analytical techniques like nano electrospray into space isn’t for the faint of heart, but I do enjoy taking these challenges and figuring out how to simplify and parameterize them for spaceflight missions.
What challenges do we face when approaching life detection on moons?
At the core of achieving these goals are two elements: an appetite for exploration, and an understanding of the high expectations to get to our destination. One big challenge to tackle is working with a limited budget – we need to be able to fund these explorative projects to learn more about what’s out there beyond our little bubble in our atmosphere.
There are also analytical challenges in getting data back. Regardless of the actual measurement techniques, we need these to survive the extreme temperatures of space travel and exploration on the moons themselves. These practical challenges require finer details before the system is perfected for leaving the lab.
Ultimately, we need to ensure that the instrument is autonomous and can fix any issues itself. Building this intelligence takes a lot of documentation and testing, but it is crucial for any space mission to work.
How important is mass spec for this research?
What we’re attempting to do with GESI is take measurements and understand more about Europa, Enceladus, and other moons’ capabilities for sustaining life. Most measurements and chemical analysis that we’d take would provide indirect measurements, whereas mass spec provides a direct measurement of weight. This allows us to put the pieces of the puzzle back together to figure out what the components are and if there are any similarities with Earth.
As arrogant as it sounds, mass spec can solve all the problems in conjunction with spectroscopy. These two pieces give confirmatory, tangential information that positively identifies if something has a molecular complexity that indicates life. In my opinion, without mass spec, every other technique would be a bit of hand waving rather than a direct measurement to the system. Everyone has a mass spectrometer, so it’s only fitting that we should also have mass spec in space.
What are your hopes for the future of life detection on moons?
I believe it's a short bet that there’s extraterrestrial life in our solar system – it’s just a matter of whether we’ll discover it in our lifetime or not. It wasn’t too long ago when we were scraping rocks together to make fire, so we’re pretty young as a species and we’ve accomplished a lot in that time. Just imagine what the next 1,000 years hold for us – hopefully our planet lasts long enough for us to experience it!
Associate Editor, The Analytical Scientist