Cometary Science Newsletter

October 2021
Michael S. P. Kelley (

ESA Archival Research Visitor Programme

To increase the scientific return from its space science missions, the European Space Agency (ESA) welcomes applications from scientists interested in pursuing research projects based on data publicly available in the ESA Space Science Archives (

The ESA Archival Research Visitor Programme is open to scientists, at all career levels, affiliated with institutes in ESA Member States and Collaborating States. Early-career scientists (within 10 years of the PhD) are particularly encouraged to apply. Applications by PhD students are also welcome.

During their stay, visiting scientists will have access to archives and mission specialists for help with the retrieval, calibration, and analysis of archival data. In principle, all areas of space research covered by ESA science missions can be supported.

Residence lasts typically between one and three months, also distributed over multiple visits. Research projects can be carried out at ESAC (Madrid, Spain) and at ESTEC (Noordwijk, Netherlands). To offset the expenses incurred by visitors, ESA covers travel costs from and to the home institution and provides support for lodging expenses and meals.

Applications received before 1 November 2021 will be considered for visits in spring/summer 2022.

For further details, including areas of research and contact information, please refer to:

or write to the programme coordinators at

Postdoctoral Research Fellow in the Study of Solar System Small Bodies

Applications are invited for a 2-year Postdoctoral Research Fellow in the Astrophysics Research Centre (ARC) at Queen's University Belfast. The successful applicant will work with Dr. Meg Schwamb to develop and exploit next-generation tools for analysing and interpreting future Solar System moving object detections from the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST). Rubin Observatory science operations are planned to begin around mid-2024, with the survey expected to discover millions of asteroids and tens of thousands of distant Solar System planetesimals. This post will focus on developing software pipelines and utilities for LSST Solar System science and applying these techniques to present-day LSST-precursor datasets, including the development of a pipeline to discover distant Solar System bodies beyond ~100 au that are not expected to be discoverable by the main Rubin Observatory Solar System Processing pipeline.

To read the full details and to apply, visit:

Application Deadline: October 13, 2021

Observing campaign for 29P/Schwassmann-Wachmann 1

29P/Schwassmann-Wachmann 1 is an always-active comet with a Centaur designation in a near-circular orbit slightly beyond the orbit of Jupiter. It outbursts many times a year and is currently undergoing one of its largest outbursts in the last few decades (8-9 magnitudes so far).

In 2019 we started coordinating a worldwide observing campaign to assist those who are studying 29P and wish to see what other plans people have for observing this important object. If you are interested in participating, please enter information about your planned (or recent past) observations at this website:

Note that signing up does not commit anyone to sharing their data, but we hope this will become a natural gathering place for researchers to see who else will be at the telescope and when, and perhaps initiate some new collaborations. If you have any questions, please direct them to Maria Womack or Gal Sarid via the "Contact Us" link on the menu.

The campaign is multi-wavelength & multi-modality and well-suited for many telescopes, such as:
Small telescopes: longterm lightcurves, outburst monitoring, coma morphology
Small-moderate: Imaging, occultations, photometry, spectroscopy
Large telescopes: Imaging, spectroscopy, photometry, occultations

More details about the campaign are at Womack et al. 2020, Minor Planet Bulletin, vol. 47-4, pp 352-354; found at this website:

and our 2020 DPS iPoster:

Maria Womack, National Science Foundation
Gal Sarid, SETI Institute

Refereed Articles

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

Photometry and long-slit spectroscopy of the split comet C/2019 Y4 (ATLAS)

  • Ivanova, O. 1,2,3
  • Luk'yanyk, I. 3
  • Tomko, D. 1
  • Moiseev, A. 4
  1. Astronomical Institute of the Slovak Academy of Sciences, Slovak Republic
  2. Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Ukraine
  3. Taras Shevchenko National University of Kyiv, Astronomical Observatory, Ukraine
  4. Special Astrophysical Observatory of the Russian Academy of Sciences, Russia

We present an analysis of the photometric and spectroscopic observations of the split comet C/2019 Y4 (ATLAS). Observations were carried out on 2020 April 14 and 16, when the heliocentric distance of the comet was 1.212 and 1.174 au, its geocentric distance 0.998 and 0.991 au, and the phase angle 52.°9 and 54.°5, respectively. The comet was observed with the 6-m BTA (Big Telescope Alt-azimuth) telescope of the Special Astrophysical Observatory (Russia) with the SCORPIO-2 (Spectral Camera with Optical Reducer for Photometric and Interferometric Observations) multimode focal reducer. The narrow-band BC and RC cometary filters in the continuum were used. We identified numerous emissions of CN, C2, C3, and NH2 molecules within the range of 3750–7100 Å. The C2/CN and C3/CN production rate ratios coincide with those of typical comets. Four fragments belonging to the coma were detected in both observational runs. We compared and analysed temporal variations of the visual magnitudes, gas productivity, and dust colour. Based on our dynamical investigation of the orbits of comets C/1844 Y1 (Great comet) and C/2019 Y4 (ATLAS), we can claim that, with high probability, the two comets do not have a common progenitor.

Monthly Notices of the Royal Astronomical Society (Published)

DOI: 10.1093/mnras/stab2306 arXiv: 2108.02988