Asteroids, Comets, Meteors (2012) 6339.pdf

METEOR SHOWERS VALIDATED BY THE CAMERAS FOR ALLSKY METEOR SURVEILLANCE (CAMS). P. Jenniskens1. 1SETI Institute, 189 Bernardo Ave, Mountain View, CA 94043 ([email protected]).

Introduction: The International Astronomical Union tium of tens of amateur astronomers in Japan, using typically has a working list containing 369 meteor showers (per Feb- wider field of view cameras and thus targeting brighter me- ruary 28, 2012), of which only 64 are considered established. teors. Also, results are derived automatically, without human The showers in need of validation were often extracted from validation of each detection. This initially raised some ques- photographic surveys prone to low-number statistics, or from tions as to the accuracy of the results, but comparison to the radar observations plagued by a strong sporadic background. CAMS data shows good agreement in radiant positions. Some are known only from visual observations. Figure 1 compares one year of CAMS data for August CAMS: The Cameras for Allsky Meteor Surveillance 10-12 with three years of published SonotaCo results on project (CAMS) is a video surveillance of the night sky to those same dates. The Perseids and delta Aquariids are read- validate as many as possible of these meteor showers. It tar- ily detected in both surveys. The kappa Cygnids (lower right) gets meteors of a brightness where the sporadic background were not active when CAMS observations were made in is relatively weak, but which occur at sufficient numbers for 2011. The eta Eridanids are well detected in the CAMS data good statistical results. and are now validated. CAMS is a three-station 60-camera meteor surveillance using Watec Wat902 H2 Ultimate video cameras, equipped with 12-mm focal length lenses. The CAMS network stations are located at Fremont Peak Observatory (operated by P. Jenniskens and R. Morales), Lick Observatory (operated by B. Grigsby), and a nearby third site currently in Sunnyvale (operated by J. Albers). The CAMS methods have been de- scribed in detail in [1]. The strength of CAMS lies in hard- ware and software, the latter developed by P. S. Gural, that is able to handle a large number of participating cameras, by

working with relatively small 20ºx30º field of view, by keep- ing the astrometric accuracy of star images in tact, by work- Figure 1: Orbital element data for Aug 10-12, from ing at 60 fields/s, by nightly re-calibration against the star CAMS (left) and from the SonotaCo network [6]. background, by careful photometry of the meteor images, and by a careful quality control from a visual inspection of Ongoing work: We will present an overview of what each coincident meteor . meteor showers CAMS is able to validate after one year of First results: As of February 28, 2012, about operation. The validated showers will be proposed to receive 30,000 meteoroid orbits have been reduced. Each clear the predicate “established” at the upcoming 2012 IAU Gen- night, some 100-300 meteoroid orbits are measured from eral Assembly in Beijing. CAMS is projected to operate for mostly +3 to +0 magnitude meteors, which create a detailed at least two more years to obtain data in nights that were picture of that night’s orbital element distribution. Major previously clouded. showers are readily detected and many minor showers are References: [1] Jenniskens P., Gural P. S., Dynne- evident in the data. So far, we have reported on the validation son L., Grigsby B. J., Newman K. E., Borden M., of the theta Aurigids (THA, IAU#390), the chi Taurids Koop M., Holman D. (2011) Icarus 216, 40-61; [2] (CTA, IAU#388), and the omicron Eridanids (OER, Jenniskens P., Gural P. S. (2011) JIMO 37, 98-121; [3] IAU#338) [1]. We also reported on the discovery of the Feb- Phillips M., Jenniskens P., Grigsby B. (2011) JIMO ruary eta Draconids [2], a periodic shower caused by the dust 39, 131-136; [4] Holman D., Jenniskens P. (2012) trail of a long-period comet, the validation of the April rho JIMO 40 (in press); [5] Jenniskens P., Duckworth H., Cygnids [3], a Jupiter Family comet, the validation of the Grigsby B. (2012) JIMO 40 (in press); Kanamori T. et July gamma Draconids [4], a long period comet shower, and al. (2009) JIMO 37, 55-62. the confirmation that meteoroids of the Daytime Arietid Additional Information: The CAMS project shower move in orbits similar to those of the Marsden Sun- website is at http://cams.seti.org. CAMS is supported grazers [5]. Much more work is still ahead. and made possible by NASA’s Planetary Astronomy The results provide a validation of meteoroid orbits program. measured in the SonotaCo video meteor project [6]. The SonotaCo network operates up to 100 cameras by a consor-