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: http://star.arm.ac.uk/highlights/2013/643.html
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Meteor showers on Earth from sungrazing comets
Figure 2. Effect of each component of ejection velocity on descending nodal distance, as a function of true anomaly when transverse (black line); radial (red line); normal component (blue line) = 1 km sтИТ1 for (a) C/2012 S1 ISON (b) Marsden family comets.
Abstract
Sungrazing comets have always captured a lot of interest and curiosity among the general public as well as scientists since ancient times. The perihelion passage of comet C/2012 S1 (ISON) at the end of this year (on 2013 November 28) is an eagerly awaited event. In this work, we do a mathematical study to check whether meteoroids ejected from this comet during its journey around the sun can produce spectacular meteor phenomena on Earth. Our calculations show that although the orbital elements of this comet are much more favourable than for most sungrazers to have its descending node near the EarthтАЩs orbit, even ejection velocities as high as 1 km sтИТ1 do not induce sufficient nodal dispersion to bring meteoroids to Earth intersection during present times. A similar result applies to NewtonтАЩs comet C/1680 V1 which has surprisingly similar orbital elements, although it is known to be a distinct comet from C/2012 S1. Our analysis also shows that for meteoroids ejected from all known sungrazing groups during recent epochs, only the Marsden family (with required ejection velocities of some hundreds of m sтИТ1) can produce meteor phenomena during present times. In a broader sense, we indicate why we do not observe visually brilliant meteor showers from frequently observed sungrazers.
Last Revised: 2013 October 11th |