This is the summary of the article from C. Joblin and J. Cernicharo:
“Interstellar clouds are sites of active organic chemistry. Many small, gasphase molecules are found in the dark parts of the clouds that are protected from ultraviolet (UV) photons, but these molecules photodissociate in the external layers of the cloud that are exposed to stellar radiation (see the photo). These irradiated regions are populated by large polycyclic aromatic hydrocarbons (PAHs) with characteristic infrared (IR) emission features. These large aromatics are expected to form from benzene (C6H6), which is, however, difficult to detect because it does not have a permanent dipole moment and can only be detected via its IR absorption transitions against a strong background source (2). On page 202 of this issue, McGuire et al. (3) report the detection of benzonitrile (c-C6H5CN) with radio telescopes. Benzonitrile likely forms in the reaction of CN with benzene; from its observation, it is therefore possible to estimate the abundance of benzene itself”.
Last Saturday, the 2nd edition of the “Illustrated talks” organized by ERCcOMICS took place at Jussieu Campus in Paris with the artist Lorenzo Palloni and the researcher Christine Joblin (one of our Principal Investigators) in the “Fête de la Science 2017” (Science Party). It was an amazing opportunity to share the astronomy and astrophysics behind the Nancosmos project, that has already a comic inspired in its science. This “Fête de la Science” is a celebration of science and technology and thousands of individuals get involved, providing general public the opportunity to discover the wonders of science. “Illustrated talks” are talks where the artist illustrates the scientist live while talking about the project. Congratulations for this outreach initiative!
Watch the full illustrated talk (in french) by Christine Joblin (research director at CNRS Toulouse) & comics artist Lorenzo Palloni at the Fête de la Science in PARIS, Campus de Jussieu, on the 14th of October 2017.
Here, some pictures from the 2nd edition of the illustrated talks with the artist Lorenzo Palloni and the researchers Christine Joblin (ERC Nanocosmos).
Christine Joblin, one of Nanocosmos’ Principal Investigators, participates in an illustrated talk during the “Fête de la Science” last 14th of October in Paris.
“Estrella” (Star in Spanish) is the name of the comic inspired by Nanocosmos.
Christine Joblin during the illustrated talk in Paris.
Lorenzo Palloni is the artist that gave life to the comic inspired by Nanocosmos “Estrella” and draw the stories live during the illustrated talk.
‘Estrella’ is a comic developed by an ERC proyect called ERCcOMIC and inspired by Nanocosmos. As the comic team believes in the power of visual storytelling, they illustrate each in a concrete, memorable and engaging way, drawing inspiration from science through stories and images.
The story of ‘Estrella’, by the artist Lorenzo Palloni, is set in 2106, and mankind is radically evolving. The NANOCOSMOS project has changed the path of astrochemistry and astrophysics, and now is the time for an elderly Estrella Leroux to pass the torch to three young scientists. Yet the story of an impossible journey of a young Estrella as a child inside the “Stardust” (a groundbreaking machine that reproduces the processes of a dying star) calls everything into question. The three budding stargazers will discover that their destiny is bound up with the mysterious Estrella’s, on the border between a surprising past and a never-so-uncertain future!
In the framework of the Nanocosmos ERC synergy project, a new analytical experimental setup called AROMA (Astrochemistry Research of Organics with Molecular Analyzer) was developed. The main purpose of this setup is to study and identify, with micro-scale resolution, the molecular content of cosmic dust analogues, including the stardust analogues that will be produced in the Nanocosmos Stardust machine in Madrid. AROMA combines laser desorption/ionization (LDI) techniques with a linear ion trap coupled to an orthogonal time of flight mass spectrometer (LQIT-oTOF). A first paper “Identification of PAH Isomeric Structure in Cosmic Dust Analogues: the AROMA setup” has just been published in The Astrophysical Journal. This is the first time that two-step LDI is coupled to a linear ion trap with MS/MS capabilities. In MS/MS experiments ions are first stored in a trap and then are fragmented under the action of photon or collision activation. The resulting fragments are then detected by mass spectrometry providing information on the molecular structure of the parent species.
The article presents the performances of AROMA with its ability to detect with very high sensitivity aromatic species in complex materials of astrophysical interest and characterize their structures. A two-step LDI technique was used, in which desorption and ionization are achieved using two different lasers which are separated in time and space. The tests performed with pure polycyclic aromatic hydrocarbon (PAH) samples have shown a limit of detection of 100 femto-grams, which corresponds to 2×108 molecules in the case of coronene (C24H12). We detected a mixture of PAH small and medium-sized PAHs in the Murchison meteorite that contains a complex mixture of extraterrestrial organic compounds. In addition, collision induced dissociation experiments were performed on selected species detected in Murchison, which led to the first firm identification of pyrene (C16H10) and its methylated derivatives in this sample.
AROMA setup, being highly sensitive, selective, spatially resolved, and owing the MS/MS capabilities enables unique chemical characterization of aromatic species in cosmic dust analogues and extraterrestrial samples. Changing the ionization source will enlarge the scope of investigated chemical species. In the future, it will be used to analyze samples from the Stardust machine, other laboratory analogues and cosmic materials such as meteorites, and interplanetary dust particles. Currently, we are developing an imaging source that will allow us to analyze samples using LDI with micrometer spatial resolution.
This research was presented in the paper “Identification of PAH Isomeric Structure in Cosmic Dust Analogs: The AROMA Setup“, published in the Astrophysical Journal (APJ), 843:34 (8pp), 2017 July 1. The authors are Hassan Sabbah (Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysique et Planétologie (IRAP); CNRS, IRAP; LCAR, Université de Toulouse, UPS-IRSAMC, CNRS, France),Anthony Bonnamy (Université de Toulouse, UPS-OMP, IRAP; CNRS, IRAP, France), Dimitris Papanastasiou (Fasmatech Science + Technology, Greece), Jose Cernicharo (Instituto de Ciencia de Materiales de Madrid (ICMM), CSIC, Spain), Jose-Angel Martín-Gago (ICMM-CSIC, Spain), and Christine Joblin (Université de Toulouse, UPS-OMP, IRAP; CNRS, IRAP, France).
Nanocosmos is a multidisciplinary team with many participants. The regional Spanish television (TVE) from Castilla-La Mancha interviewed some of the members of the FOTOAIR group, whose participation in our project is led by Elena Jiménez, in the Chemistry and Physics Department of the Castilla-La Mancha University, in Ciudad Real. (From 16:20 to 19:99).
Our cosmos is full of star dust, the ashes of stars that died and ejected their matter to the interstellar medium, filling it with dust and gas. When solar like stars consume the hydrogen in their cores, we say that their “main sequence” stage is finished and they begin their final phase. Because IRC+10216 is the high mass-loss star closest to us, it is the best studied evolved star and it seems to keep a secret: it is not alone.
As solar like stars evolve into the Asymptotic Giant Brach (AGB) phase, they eject large amounts of material into the interstellar medium, forming a circumstellar envelope around these objects. Thanks to the Atacama Large Millimeter /submillimeter Array (ALMA) we can now study the innermost regions of the circumstellar envelopes of those evolved stars with unprecedented precision and sensitivity.
IRC +10216 is the best studied evolved carbon-rich star. Located at an estimated distance of 424 light years, this AGB star is the high mass-loss star closest to us. This proximity has allowed the detection of a large number of molecules in its circumstellar envelope. These detections have in turn provided a deep and fruitful study of the chemical processes occurring in the ejected material of this star. The importance of these regions is fundamental since it covers the zone where the dust is formed and accelerated, and the dust grains trigger many chemical reactions.
But, after many studies from different research groups, one question remained unanswered: why was the gas shells irregularly distributed around the central star? In fact, the ejecta around it go from roughly spherical at the large scale, to relatively complex in the innermost regions.
There was a theory to explain the shape of the envelope of this evolved star.
Spiral structure, a companion star?
Understanding the structure of the circumstellar envelope and the molecular gas around this star is fundamental to reveal the chemical processes therein. For example, a clumpy structure may allow the UV radiation coming from the interstellar medium to reach the inner regions of the molecular gas and trigger chemical reactions.
Also the kinematics of these ejecta allows us to study the ejection process from the inner zones and to infer the mechanism involved: the data suggests that the matter released by the ejecta is slowly expanding and rotating.
As gas shells ejected by the evolved star are expected to be spherical, the irregular distribution around it, forming a spiral front, can be explained by the presence of a companion star.
Salts as tracers to confirm the companion star
Astrochemistry uses the data obtained by the different instruments to unveil the role of the different molecules in the chemical processes that take place in the Universe.
For instance, the emission from molecules such as CO and SiS has been found to show the spiral structure of IRC +10216 while that from radicals such as CN or C3H show that the abundance of these molecules is enhanced relatively far from the star. The shape of this distribution fits with the theory of a companion star.
In this work, the metal-bearing molecules were expected to probe the innermost regions of the circumstellar envelope around IRC +10216. The first author, Guillermo Quintana- Lacaci, says “Certain characteristics of the molecules affect to their emission, for instance Sodium Chloride (NaCl) and Potassium Chloride (KCl) provide much better contrast (dynamic range) to see weak structures in regions where other molecules as (Al)-bearing molecules can’t. In particular, NaCl confirms the presence of a face-on spiral extending to the innermost regions of IRC +10216 as well as it shows that this spiral structure is rotating.”
More observations with high angular and spectral resolution would allow the researchers to better constrain the characteristics of the structures detected here, but with this work, the presence of a star orbiting IRC+10216 becomes the explanation that fits the most with the rotating spiral structure seen around it.
The results of this work were published in the paper “HINTS OF A ROTATING SPIRAL STRUCTURE IN THE INNERMOST REGIONS AROUND IRC+10216”, by G. Quintana-Lacaci (Group of Molecular Astrophysics, ICMM, CSIC, Spain); J. Cernicharo (Group of Molecular Astrophysics, ICMM, CSIC, Spain); M. Agúndez (Group of Molecular Astrophysics, ICMM, CSIC, Spain); L. Velilla Prieto (Group of Molecular Astrophysics, ICMM, CSIC; Centro de Astrobiología, INTA-CSIC, Spain); A. Castro-Carrizo (Institut de Radioastronomie Millimétrique, France); N. Marcelino (INAF, Istituto di Radioastronomia, Italy); C. Cabezas (Grupo de Espectroscopía Molecular (GEM), Unidad asociada CSIC, Universidad de Valladolid (UVA), Spain); I. Peña (GEM, Unidad asociada CSIC, UVA, Spain); J. L. Alonso (GEM, Unidad asociada CSIC, UVA, Spain); J. Zúñiga (Dpto. de Química-Física, Faculdad de Química de la Universidad de Murcia, Spain); A. Requena (Dpto. de Química-Física, Faculdad de Química de la Universidad de Murcia, Spain); A. Bastida (Dpto. de Química-Física, Faculdad de Química de la Universidad de Murcia, Spain); Y. Kalugina (LOMC-UMR 6294, CNRS-Université du Havre, France; Department of Optics and Spectroscopy, Tomsk State University, Russia); F. Lique (LOMC-UMR 6294, CNRS-Université du Havre, France); and M. Guélin (Institut de Radioastronomie Millimétrique; LERMA, Observatoire de Paris, PSL Research University, CNRS, France).
Rosa Montero is a famous Spanish writer that recently visited the ICMM, where the Stardust machine is being built. This weekend she wrote in the El País Newspaper about her impressions. You can read the article here.
January and February are being good months for the NANOCOSMOS outreach on the hispanophone Mass Media. Many newspapers published last week an interview with José Cernicharo (one of the three Principal Investigators of the project). You can read one of them, published in “La Opinión, A Coruña”, in this link.
The interview has also been published in other regional newspapers as “La Nueva España”, “Levante (El Mercantil Valenciano)”, “Faro de Vigo”, “La Provincia, diario de Las Palmas” and “La Opinión de Tenerife”.
Last week, Carlos Herrera, a well-known Spanish journalist, interviewed one of the Nanocosmos Principal Investigators, José Ángel Martín Gago, about the Stardust Machine. You can listen to the podcast of the program (in Spanish), “Herrera en COPE”, in this link.