Cometary Science Newsletter

Issue
43
Month
October 2018
Editor
Michael S. P. Kelley (msk@astro.umd.edu)

Postdoctoral Position in Cometary Science/Astrochemistry

We are currently seeking expertise in millimeter/submillimeter spectroscopy and observations with ground-based facilities including single dish and interferometers at these wavelengths (e.g. ALMA, JCMT, IRAM 30m, NOEMA, APEX, etc.). Familiarity with cometary science and/or astrochemistry is preferred. Details on the position can be found through NASA’s Postdoctoral Program (NPP).

The Theory and Observation Group in the Astrochemistry Laboratory at NASA Goddard Space Flight Center (Greenbelt, MD) undertakes research in astrochemistry and molecular astrophysics aimed at understanding those astronomical environments that are to be studied by current and future NASA missions. We are particularly interested in the chemical connections between different stages in the Galactic evolution of matter, specifically issues related to the birth and death of stars, the formation and evolution of the Solar System, and prebiotic chemistry.

Applications are due November 1, 2018. Details about NASA Postdoctoral Positions, applications, eligibility, benefits can be found through their webpage.

We encourage interested applicants to please contact us with a brief description of research interests, experience, and a current CV no later than October 12, 2018. Please send information to Stefanie Milam (stefanie.n.milam at nasa.gov).

Postdoctoral Position in Cometary Atmospheres

The Physics Department at Auburn University invites applicants for a post-doctoral research position within the Atomic, Molecular and Optical Physics group in the field of cometary atmospheres.

The successful candidate will analyze images of comet 9P/Tempel 1 taken during the flyby of NASA’s Deep Impact spacecraft. These images were acquired with comet specific narrowband filters and allow for a detailed study of the gas and dust surrounding the nucleus. The goal of this project is to connect this gas and dust to specific areas on the nucleus, to investigate chemically heterogenous outgassing, and to identify atomic and molecular processes that alter the inner coma.

Familiarity with planetary science and/or atomic and molecular physics is preferred. Substantial familiarity with a commonly-used scientific programming language (e.g. IDL, Python) is highly desirable. Review of applications will begin October 19th, 2018 and continue throughout the year as the positions become available.

The contact for this activity is Prof. Dennis Bodewits (dennis@auburn.edu).

More details and information on how to apply can be found at: http://www.auburn.edu/~dzb0059.

Refereed Articles

Abstracts of articles in press or recently published. Limited to 3000 characters.

The extraordinary composition of the blue comet C/2016 R2 (PanSTARRS)

  • N. Biver 1, 5
  • D. Bockelée-Morvan 1
  • G. Paubert 2
  • R. Moreno 1
  • J. Crovisier 1
  • J. Boissier 3
  • E. Bertrand 4, 5
  • H. Boussier 4, 5
  • F. Kugel 6, 5
  • A. McKay 7
  • N. Dello Russo 8
  • M. A. DiSanti 9
  1. LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, Meudon, France
  2. IRAM, Avd. Divina Pastora, 7, 18012 Granada, Spain
  3. IRAM, 300, rue de la Piscine, F-38406 Saint Martin d'Heres, France
  4. Astronomical Ring for Access to Spectroscopy (ARAS) (http://www.astrosurf.com/aras/intro/intro.htm)
  5. Commission des comètes, Société Astronomique de France, 3 rue Beethoven, F-75016 Paris, France
  6. Observatoire de Dauban, 04 Banon, France
  7. NASA GSFC/USRA, 8800 Greenbelt Rd, Greenbelt, MD 20771, USA
  8. Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd., Laurel, MD 20723, USA
  9. NASA Goddard Center for Astrobiology, NASA GSFC, Mail Stop 690, Greenbelt, MD 20771, USA

We present a multi-wavelength study of comet C/2016 R2 (PanSTARRS). This comet was observed on 23-24 January 2018 with the IRAM 30m telescope, and in January to March 2018 with the Nancay radio telescope. Visible spectroscopy was performed in December 2017 and February 2018 with small amateur telescopes. We report on measurements of CO, CH3OH, H2CO and HCN production rates, and on the determination of the N2/CO abundance ratio. Several other species, especially OH, were searched for but not detected. The inferred relative abundances, including upper limits for sulfur species, are compared to those measured in other comets at about the same heliocentric distance of about 2.8 AU. The coma composition of comet C/2016 R2 is very different from all other comets observed so far, being rich in N2 and CO and dust poor. This suggests that this comet might belong to a very rare group of comets formed beyond the N2 ice line. Alternatively, comet C/2016 R2 (PanSTARRS) could be the fragment of a large and differentiated transneptunian object, with properties characteristic of volatile-enriched layers.

Astronomy and Astrophyics (In press)

DOI: 10.1051/0004-6361/201833449 arXiv: 1809.08086