Edwin L. Aguirre
Melikechi, who is an expert on optics and laser spectroscopy, is a member of the science team for SuperCam
, one of the main instruments onboard Perseverance. SuperCam will conduct experiments by zapping the surface of Mars with a powerful laser.
Perseverance will spend the next seven months cruising through 293 million miles of interplanetary space before its scheduled arrival at its Martian landing site, called Jezero Crater, on Feb. 18, 2021. The 2,300-pound robotic explorer is designed to better understand the geology, geochemistry and climate of Mars and to seek signs of ancient microbial life.
The launch of Perseverance follows previous NASA rover missions to Mars – Sojourner in 1997, Spirit and Opportunity in 2004 and Curiosity in 2012 – and marks the beginning of a new phase in the exploration of the red planet.
Here, Melikechi shares some insight into his research as well as the future of human-crewed mission to Mars.
Q. Perseverance will use a remote-sensing technique called laser-induced breakdown spectroscopy, or LIBS, to study the chemical composition of the Martian surface. How does it work?
A. The rover’s SuperCam will analyze the surface composition by firing intense pulses of laser at distant rocks, boulders or sediments. The laser will vaporize a small portion of the target material, and the resulting flash of light is picked up by a detector, called a spectrograph, which identifies the different chemical elements present in the target. The data is then transmitted to Earth for analysis.
Q. You are also involved with the LIBS experiment onboard Curiosity, the predecessor to Perseverance. What do you expect to accomplish with Perseverance that you have not been able to do with Curiosity?
The two rovers have different, but complementary, scientific goals. Curiosity
, which landed on Mars on August 6, 2012, is still operational. In line with its goals, Curiosity’s investigations have provided new information about the geology and the environment of Mars. It has revealed that a few billion years ago, Mars had liquid water that formed lakes and rivers on its surface.
The Perseverance rover is capable of shedding light on scientific questions that Curiosity cannot address. For example, Perseverance will be able to identify a broad range of organic molecules that could yield new information on biological signatures formed in ancient Martian environments. This would contribute to the planning of future Mars missions focused on astrobiology. Curiosity is not equipped for such studies.
Q. LIBS has also been used in a wide range of applications on Earth, including cancer research. Can you give some examples?
My research group has successfully demonstrated the use of LIBS in detecting biomarkers for both ovarian cancer
and melanoma through a single drop of blood. Recently, we were awarded a seed grant by the university to evaluate the use of LIBS as a quick and simple test in detecting spectral signatures of SARS-CoV-2
, the virus that causes COVID-19, in blood, saliva and urine samples.
Q. What does the Mars 2020 mission mean for the exploration of the red planet by human astronauts, currently planned by the 2030s?
A. One of the goals of Perseverance is to help prepare for human exploration of Mars by characterizing the part of the planet – Jezero Crater – where Perseverance will be operating and by investigating new technologies capable of producing oxygen on-site from carbon dioxide in the Martian atmosphere. This could provide oxygen for rocket fuel and breathable air for future missions.