Annual meteor showers at Venus and Mars: lessons from the Earth

Abstract

We have generated a list of cometary bodies as well as known meteoroid streams that we consider to be prime candidates for producing significant meteor activity in the atmospheres of Venus and Mars. To compile this list, we defined a quantitative criterion based on catalogued properties of comets such as their dynamical class, orbital period and absolute brightness as well as the proximity of their orbits to the planetary orbits. This procedure improves over previous work that considered only this latter quantity as the sole criterion for meteor shower parentage at those planets. The list of Martian (Venusian) candidates contains six (eight) Halley-type comets, 11 (six) intermediate long-period comets, eight (nine) showers originating from known meteoroid streams of Encke or Jupiter-family type and one inert object in a comet-like orbit. Based on these findings, we conclude that (i) meteor shower activity at those planets would be variable on a seasonal scale, just as it is at the Earth, (ii) Venusian and/or Martian meteor showers from bright long-period comets, a population with no representatives in the Earth's vicinity, are a possibility, and (iii) numerous opportunities exist for sampling known Encke-type and Jupiter-family showers to probe their spatial structure far from the Earth's orbit. We calculate local observing circumstances of these showers to aid in their future observational confirmation and characterization.