Letters of Intent received in 2021

LoI 2023-2137
Astrochemistry VIII: From the First Galaxies to the Formation of Habitable Worlds

Topics

1) From the high-redshift universe to local galaxies
1a) Atomic, and molecular tracers at z > 6
1b) Dust, Atomic, and molecular tracers of peak star formation (z ~ 2)
1c) Molecular tracers of the central engine in AGN
1d) Mapping Molecular Cloud Chemistry on Galactic Scales
2) The Milky Way: Chemical Transformations with star formation and feedback
2a) Molecular tracers of the central engine
2b) Star formation in the Milky Way
2c) Chemical tracers of feedback (PDRs, winds, and outflows)
2d) General cloud chemistry (PAH detection in dark clouds)
2e) Development of molecular complexity
2f) Evolved stars
3) Planet Formation and Exoplanets
3a) Protostars and protostellar disk chemistry
3b) Protoplanetary disk chemistry
3c) Exoplanetary atmosphere composition and chemistry
3d) Linking formation to exoplanet characteristics
4) The Solar System Record
4a) Meteoritic composition and planet formation
4b) Cometary and Asteroid composition
4c) Giant planet and satellite composition
5) Grounding Information: Laboratory Astrophysics and Theory
5a) Gas phase chemistry
5b) Ices and Molecular Complexity
5c) New techniques in molecular spectroscopy
5d) Planetary and satellite atmospheres
6) Looking to the future (missions and facilities)

Rationale

Astrochemistry is now an established branch of modern astrophysics linking to the early universe and down to compositional anomalies measured in meteorites that are one part in a thousand, in between lies the burgeoning link of this field to understanding the compositions of a multitude of planets ranging from gas giants to potentially habitable worlds.
In the past 30 years, IAU symposia have been at the focal point of astrochemistry and have actively fostered growth of this field. In this time there have been 7 symposia from the first held in 1985 in Goa, India (IAU 120) to the last held in Puerto Varas, Chile (IAU 332).

The symposium in Chile was held in 2017 when ALMA had only a few years of operation, the wealth of information from Rosetta only scratched the surface, and the study of exoplanet atmospheric composition was beginning to explode. Since that time, ALMA's contribution to astrochemistry has grown enormously. Ionized carbon and oxygen have been detected with ALMA in the high redshift (z > 6) galaxies, probing the earliest stages of galaxy formation in the universe. ALMA has also detected ions such as CH+ in vast, turbulence-dominated halos surrounding galaxies at the peak of star formation in the Universe at z ~ 2. Astrochemical studies in the local Universe have provided the first detection and identification of polycyclic aromatic hydrocarbons (PAHs) in space, with a puzzling twist that these PAHs are forming in cold (10 K) dark molecular clouds! In addition to ALMA, NOEMA and the SMA are using the power of broadband spectroscopy to explore the chemical composition in protostars down to the protostellar disk scales. The links between the chemistry of planet formation and the actual composition of exoplanetary atmospheres are slowly evolving into a vibrant and exciting scientific topic that has concurrently strengthened links to cosmochemical studies of solar system materials. Throughout, our understanding of star formation has been enhanced by beautiful images of magnetic field structure surrounding star forming cores by Planck and SOFIA that connect down to smaller scales with ALMA. The launch of the James Webb Space Telescope (JWST) in late 2021 will provide another strong contribution to our ability to explore the chemistry of the universe, in particular, molecular ices. Sensitive near to mid-infrared JWST spectrometers will renew our ability to observe major molecular ingredients such as water and carbon dioxide and a host of other key CHONS species to probe chemistry in exoplanetary atmospheres, protoplanetary disks, and beyond.

Our proposal is to hold our symposium in 2023 during the week of June 19. The meeting site is planned to be in Traverse City, Michigan (United States) situated on the shores of Lake Michigan. By this time some of the fruits of JWST will be in evidence as several early release and guaranteed time programs will have their results out. Further, both NOEMA and ALMA have several accepted large programs that focus on the composition of protostars and disks. Our conference is aimed to bring our field together and showcase these disparate field-leading efforts.

Bringing our field together is also important as the life-blood of astrochemistry is the direct link to the chemistry and physics communities through laboratory studies of chemical kinetics, molecular spectroscopy, and studies of ice surface chemistry. This connection is, and has been, central to our field and an area that our symposia strongly highlight. For instance, the detection and identification of an interstellar PAH was enabled through direct links between laboratory spectroscopy and observations at centimeter wavelengths. Given the breadth of our field, we will ensure our links to laboratory astrophysics, astrobiology, and exoplanets through their inclusion in our SOC.

Above, we list a broad range of topics that will be interspersed throughout the symposium, which will be held over the course of 4.5 days. As per our tradition, each discussion area will start with invited reviews, followed by invited contributions in the same or related topical area. In our two online symposia held in 2020 and 2021 (Astrochemical Frontiers - Quarantine edition 1 and 2) we focused on contributed talks in order to keep our connections alive during this difficult time. For this symposium, our plans are to provide the young scholars with the ability to put “invited contribution” on their resume. Our field is quite diverse in terms of gender and geographical balance. Through the SOC, we will ensure that the invited speakers capture this diversity.