Quick search Find article
Quick search
Find article

THE EXTREMELY ANOMALOUS MOLECULAR ABUNDANCES OF COMET 96P/MACHHOLZ 1 FROM NARROWBAND PHOTOMETRY

FREE ISSUE

David G. Schleicher

Show affiliations


Narrowband-filter photometry of Comet 96P/Machholz 1 was obtained at Lowell Observatory during the comet's 2007 apparition. Production rates of OH, CN, C2, C3, and NH were derived from these data sets, and the quantity A(θ)—a proxy measure of the dust production—was also calculated. Relative abundances, expressed as ratios of production rates with respect to OH (a measure of the water abundance), were compared to those measured in other comets. Comet Machholz 1 is shown to be depleted of CN by about a factor of 72 from average, while C2 and C3 are also low, but "only" by factors of 8 and 19, respectively, from "typical" composition (based on an update to the classifications by A'Hearn et al.). In contrast, NH is near the mid-to-upper end of its normal range. This extremely low CN-to-OH ratio for Machholz 1 indicates that it is either compositionally associated with Comet Yanaka (1988r; 1988 Y1), which was strongly depleted in CN and C2, but not NH2, or represents a new compositional class of comets, since Yanaka had a much greater depletion of C2 (>100×) than did Machholz 1 (8×). Evidence strongly suggests that the extremely anomalous compositions of these two comets are primordial rather than from recent thermal processing. It remains unclear whether these comets formed at a location in our solar system with unusual conditions and a low probability of being gravitationally perturbed into the inner solar system, or if one or both objects are interstellar interlopers.


Keywords

comets: individual (96P/Machholz 1); techniques: photometric


Dates

Issue 5 (2008 November)

Received 2008 June 30, accepted for publication 2008 September 10

Published 2008 October 15



  1. The Extremely Anomalous Molecular Abundances of Comet 96p/Machholz 1 from Narrowband Photometry

    David G. Schleicher 2008 The Astronomical Journal 136 2204

  2. Spin glass stiffness in zero dimensions

    Stefan Boettcher 2006 J. Phys. A: Math. Gen. 39 10641

  3. Block-copolymer assisted synthesis of arrays of metal nanoparticles and their catalytic activities for the growth of SWNTs

    Sreekar Bhaviripudi et al 2006 Nanotechnology 17 5080

  4. Kinematic Disturbances in Optical Rotation Curves among 89 Virgo Disk Galaxies

    Vera C. Rubin et al. 1999 The Astronomical Journal 118 236

  5. Ongoing Gas Stripping in the Virgo Cluster Spiral Galaxy NGC 4522

    Jeffrey D. P. Kenney and Rebecca A. Koopmann 1999 The Astronomical Journal 117 181

  6. Environmental Effects in Clusters: Modified Far-Infrared-Radio Relations within Virgo Cluster Galaxies

    E. J. Murphy et al. 2009 ApJ 694 1435

  7. Wavelets in mathematical physics: q-oscillators

    Palle E T Jorgensen and Anna Paolucci 2003 J. Phys. A: Math. Gen. 36 6483

  8. Infrared Spectra of Isolated Protonated Polycyclic Aromatic Hydrocarbon Molecules

    Harald Knorke et al 2009 ApJ 706 L66

  9. Ten New and Updated Multiplanet Systems and a Survey of Exoplanetary Systems

    J. T. Wright et al. 2009 ApJ 693 1084

  10. Don't look at the Sun: imparting the dangers of solar observation

    Michael J Ruiz 2005 Phys. Educ. 40 411

Users also read

What's this?
This innovative new feature generates a list of articles 'also read' by other users based on them reading the original article. Article abstracts citations and references are all considered and weighted accordingly. We hope that this will help you find relevant papers for your research.

  1. The Unusual Spectrum of Comet 96P/Machholz

View by subject




Export








Please login to access our web services, or create an account if you don't yet have one.

You must have cookies enabled in your web browser to be able to login.

Username
Password

Forgotten your password? Get a new one here.