AnnualReport2020

ANALOGUES IN THE SEARCH FOR LIFE ON
MARS
EXPERIMENTAL MEASUREMENTS OF
ATMOSPHERIC CHEMICAL REACTIONS
Dr Barbara Cavalazzi
LE STUDIUM / Marie Skłodowska-Curie
Research Fellow
Smart Loire Valley General Programme
From: University of Bologna - IT
In residence at: Center for Molecular
Biophysics (CBM) - Tours
Nationality: Italian
Dates: October 2020 to October 2021
Barbara Cavalazzi is an Associate Prof. at the
Univ. of Bologna and Adjunct Prof. at the Univ. of
Johannesburg. She is a geobiologist/astrogeologist
expert in biosignatures preserved in rocks and a
reputed field geobiologist. In 2008 she received
the NASA-NAI and Lewis and Clarck Found for
Exploration and Field Research in Astrobiology
Award, in 2017 the Medal Science from the
Alexandria Univ. In 2016 and 2020, she join the
scientific board of the Institute of Advanced Studies
and the Collegio Superiore of the Univ. of Bologna,
respectively. In 2020 she has member of NASA-
ESA Mars Sample Return Science Planning Group
Phase 2 and of the International Mars Exploration
Working Group. At moment, she is involved in the
Europlanet-H24 RI EU project and in the Pan-
African Planetary and Space Science Network of
the Intra-Africa Academic Mobility Scheme. Since
2019, she is president of the European Astrobiology
Network Association – EANA.
This project focuses on the search for traces of fossil life on Mars and related
habitats, and is directly relevant for the forthcoming astrobiological missions
to Mars.
Martian life is most likely to have been (and may still be) very primitive,
leaving, at most, the fossil traces of organisms similar to terrestrial
anaerobic microbes. Their biosignatures will be subtle, diluted by a mineral
matrix, and easily confused by abiotic bacteriomorphs. Thus, criteria that can
aid distinction bacteriomorphs from bona fide microbial fossils is of prime
importance in the run-up to the missions for scientific testing of the payload
instruments. As well, to be able to reconstruct field geobiological analogues
for Mars will help in detecting rocks with a high fossilization potential.
The main target of this project is to compile a comprehensive catalogue
or book including Mars-analogue environments and a broad range of
biosignatures of relevance to Mars. There are many studies concerning
different types of Mars analogue organisms and there have been some
previous generalisations regarding biosignatures on Mars, but that’s what
is lacking, at this very critical stage in the lead-up to the Mars missions.
Such work will be particularly useful especially to those directly involved in
the search for Martian life, from students (who will be the next generation of
astrobiologists and planetary scientists) to established scientists.
Within this timely space mission context, the objectives of this project are:
1) to study biosignatures from carbonates cropping out at the Djiboutian
area of the Afar depression, an analogue for the surface of Mars during
the Noachian/Hesperion eras (~4-3.5 Ga); 2) To create a catalogue of Marsrelevant
terrestrial analogues and biosignatures in the form of a review
article and a photographic textbook, for which there is an urgent and timely
need to help prepare the scientists involved in the Mars 2020 and ExoMars
2020 missions.
To date in collaboration with Dr Westall, I have prepared for analyses the
samples from Djiboutia area, discussed with the Springer Ed. the project for
the book Planteray Filed Analogues, I am defining the table of content with
Dr. Westall and the Publisher.
Dr Max McGillen
LE STUDIUM Research Fellow
ARD 2020 PIVOTS Programme
From: University of Bristol - UK
In residence at: The Institute of Combustion
Aerothermal Reactivity and Environment
(ICARE) - Orléans
Nationality: British
Dates: September 2018 to December 2018
April 2019 to September 2019
January 2020 to March 2020
Dr Max McGillen has worked in several laboratories
in the UK, and has earned international
experience in the USA, Ireland and France.
He has worked in a variety of areas including
laboratory measurements, field measurements
and structure activity relationships. This has
resulted in a broad understanding of atmospheric
chemistry. Max has been the recipient of an
ESF exchange grant, a Marie Skłodowska Curie
Research Fellowship, and is now enjoying his
status as a Le Studium Fellow. He is also an active
member of an international expert panel on the
evaluation of structure-activity relationships, and
is currently leading their efforts to compile and
review an extensive atmospheric kinetic database.
The goal of this project is to obtain accurate and precise data on the rates and
products associated with chemical reactions occurring in the atmosphere,
using a wide variety of measurement techniques available at ICARE. Some of
these measurements are challenging and the fellow will be required to utilize
his experience to try to address long-standing uncertainties within atmospheric
chemistry. He will also helping to develop experimental protocols and techniques
at the host laboratory.
Achievements so far: The fellow has been focusing on the reaction of sulphur
dioxide with the OH radical. This is a very important reaction in atmosphere,
since it leads to the formation of sulphuric acid, which is of crucial importance
to aerosol formation, and therefore has a major effect in terms of air pollution
and climate change. However, there remain some key uncertainties in this
reaction rate, primarily related to the effect of pressure on this reaction. To
begin with, a thorough survey of the literature regarding this reaction was
performed, and the gaps in the knowledge were assessed. Accordingly the fellow
has conducted a series of careful measurements in the presence of a variety of
bath gases (helium, nitrogen and argon) using the pulsed laser photolysis–laser
induced fluorescence (PLP-LIF) technique. The maximum pressure available to
the PLP-LIF technique is ~400 Torr (below atmospheric pressure), and therefore
to complement this technique, a series of simulation chamber measurements
have been made in the presence of nitrogen, oxygen, argon and air at 760
Torr. By measuring this reaction using different techniques over a wide range
of conditions, we have made definitive progress regarding understanding the
pressure dependence of this reaction. This allows us to compare with previous
measurements, and to determine, which, if any, are accurate. It is expected that
this work will result in a publication that will be of interest to the atmospheric
chemical community. The fellow has also taken the responsibility of instructing a
PhD student, Ms. Hajar Elothmani, in atmospheric chemistry and the techniques
involved in making accurate gas-phase kinetic measurements. Dr McGillen has
also supervised a project of a post-doctoral appointee, Dr Soukaina Foulal,
which investigates the impact of jet-fuel emissions upon air quality. This has
led to an ongoing collaboration with Dr Bernard Aumont at the Laboratoire
Interuniversitaire des Systèmes Atmosphériques in Paris, which will also be
worthy of publication in the future.
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Dr Frances Westall
Host Scientist
Dr Frances Westall, geologist and astrobiologist, is
Director of Research at the CNRS-Centre de Biophysique
Moléculaire. Her multidisciplinary scientific career
encompassed geology, planetology, geomicrobiology,
prebiotic chemistry, and astrobiology. She is internationally
renowned for her research on the geological context of
the origin of life and the earliest traces of life on Earth.
She was part of the science definition team that led to the
ExoMars 2022 mission to search for life on Mars. Co-PI of
the microscope CLUPI and Co-I on other instruments, she
is the main biosignatures expert for the mission. She was
president of the CNRS GDR Exobiology, president of the
European Astrobiology Network Association, chair of the
COSPAR Panel on Exploration and member of numerous
national and international committees including the CNES
Comité de Programmes Scientifiques, the H2020 Space
Advisory Group, the ESA Human, Exploration and Science
Advisory Group, the ESA Space Science Advisory Group and
many others. She received the Medal of the Italian Chemical
Society (2013), the Alfred Dumont Medal (Belgium), and was
awarded an Honorary Fellowship of the International Studies
Institute, Bologna as well as numerous awards from NASA.
Image Credit: NASA/JPL-Caltech
Dr Abdelwahid Mellouki
Host Scientist
Dr Abdelwahid Mellouki’s undergraduate and
graduate studies were conducted in the Universities
of Tours, Orleans and Paris 7 (France). He spent
two years as a Research Associate at the National
Oceanic and Atmospheric Administration’s
Aeronomy Laboratory (Boulder-Colorado). His
main research fields are Chemical Kinetics,
Atmospheric Chemistry, Air Pollution and Climate
change. He joined the CNRS in 1992, where he is
currently a Research Director at ICARE in Orléans
(France), leading the Atmospheric Reactivity Group.
He has been nominated National Distinguished
Professor at Shandong University (China) and
Guest Professor at the Chinese Academy of
Science (CAS/ RCEES-Beijing) and Fudan University
(Shanghai). His research over focus on many
aspects of atmospheric chemistry, including the
study of the atmospheric oxidation mechanisms
of anthropogenic and biogenic carbon-containing
species and halogen chemistry. He is author
or coauthor of over 200 scientific publications/
chapters related to atmospheric chemistry.
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