CometWatch October 2019

Welcome to The October Comet Watch. This month Neil Norman and Myself talk with Daniel Bamberger from Northolt Branch Observatories

British Astronomical Association Comet Section Visual observations page
https://www.ast.cam.ac.uk/~jds/

Seiichi Yoshida’s page
http://www.aerith.net/comet/weekly/current.html

The German comet group page
http://kometen.fg-vds.de/fgk_hpe.htm

Liga Iberoamericana de Astronomia
http://wp.me/PS5tw-bt

The Sky Live – Comets
https://theskylive.com/comets

Comet Chasing http://www.cometchasing.skyhound.com/

Northolt Branch Observatories: Facebook https://www.facebook.com/NBObservatories/ and Twitter https://twitter.com/nbobservatories?lang=en
Predicted trajectory and brightness of C/2017 T2: http://aerith.net/comet/catalog/2017T2/2017T2.html

A modern description of the Afrho parameter and its use: “The calculation ofAfrho and mass loss rate for comets” http://www.lpl.arizona.edu/alllpl/AfrPaperPubl.pdf
KOPR Software for Afrho measurement: https://www.facebook.com/groups/631665453704477/

Michael A’Hearn’s invention of the Afrho parameter, in a 1980 paper about comet Bowell (behind paywall): “Comet Bowell (1980b): Measurement of the optical thickness of the coma and particle albedo from a stellar occultation” https://www.sciencedirect.com/science/article/abs/pii/0019103584900903

Michael A’Hearn, the astronomer who introduced Afrho: https://en.wikipedia.org/wiki/Michael_A%27Hearn

A’Hearn was Principle Investigator of the EPOXI spacecraft, which visited comet Hartley 2. It was first planned to go to comet 85D/Boethin, but that comet could not be found (it probably disintegrated): https://en.wikipedia.org/wiki/85D/Boethin

Comet 29P/Schwassmann-Wachmann: https://en.wikipedia.org/wiki/29P/Schwassmann%E2%80%93Wachmann

A guide to observing the outbursting comet 29P/Schwassmann-Wachmann: “Observing the outbursting comet 29P/Schwassmann-Wachmann (Richard Miles)” https://www.britastro.org/node/18562

Daniel Bamberger’s most recent observation report about 29P/Schwassmann-Wachmann (20 October 2019): https://www.facebook.com/NBObservatories/posts/2832095670158619

Hubble observations of 29P, taken in October 2019 (will be made public in April 2020, after the proprietary period): “Comet outburst target of opportunity (HST Proposal 15965, Dennis Bodewits)” https://archive.stsci.edu/proposal_search.php?id=15965&mission=hst

The two proposed NASA missions to 29P/Schwassmann-Wachmann: “Centaurs Rising: NASA Eyes Missions to Weird Asteroid-Comet Hybrids” https://www.space.com/nasa-centaur-missions-centaurus-chimera.html

The interstellar comet 2I/Borisov: https://en.wikipedia.org/wiki/2I/Borisov

Hubble observations of 2I/Borisov: https://www.nasa.gov/feature/goddard/2019/hubble-observes-1st-confirmed-interstellar-comet

The most detailed paper yet about comet 2I/Borisov, published the day after this Comet Watch episode was recorded – including precovery observations, size estimates and spectroscopic information: “Characterization of the Nucleus, Morphology and Activity of Interstellar comet 2I/Borisov by Optical and Near-Infrared GROWTH, Apache Point, IRTF, ZTF, Keck and HST Observations” https://arxiv.org/abs/1910.14004

Daniel Bamberger’s paper about “the Difficulty of Predicting Stellar Occultations by Interstellar Comet 2I/Borisov”: https://iopscience.iop.org/article/10.3847/2515-5172/ab4efb

“Disintegrating In-Bound Long-Period Comet C/2019 J2”, about a small comet that disintegrated at 1.9 AU from the Sun (similar to 2I/Borisov’s perihelion distance): https://arxiv.org/abs/1909.01964

“New Insights into Interstellar Object 1I/2017 U1 (`Oumuamua) from SOHO/STEREO Nondetections”: https://arxiv.org/abs/1910.10303

Zdenek Sekanina’s hypothesis of “1I/`Oumuamua As Debris of Dwarf Interstellar Comet That Disintegrated Before Perihelion”: https://arxiv.org/abs/1901.08704

Comet 2I/Borisov in the exoplanet database (added as an interstellar object), including a comprehensive list of publications about 2I/Borisov: http://exoplanet.eu/catalog/2i/borisov/

51 Pegasi b, the first known exoplanet: https://en.wikipedia.org/wiki/51_Pegasi_b

A music video about the search for exoplanets (including the story of 51 Pegasi b’s discovery, and the power of statistics): “Whole New Worlds: An Aladdin History of Exoplanets” https://www.youtube.com/watch?v=gai8dMA19Sw