A survey of debris trails from short-period comets

Abstract

We observed 34 comets using the 24 micron camera on the Spitzer Space Telescope. Each image contains the nucleus and covers at least 10^6 km of each comet's orbit. Debris trails due to mm-sized or larger particles were found along the orbits of 27 comets; 4 comets had small-particle dust tails and a viewing geometry that made debris trails impossible to distinguish; and only 3 had no debris trail despite favorable observing conditions. There are now 30 Jupiter-family comets with known debris trails, of which 22 are reported in this paper for the first time. The detection rate is >80%, indicating that debris trails are a generic feature of short-period comets. By comparison to orbital calculations for particles of a range of sizes ejected over 2 yr prior to observation, we find that particles comprising 4 debris trails are typically mm-sized while the remainder of the debris trails require particles larger than this. The lower-limit masses of the debris trails are typically 10^11 g, and the median mass loss rate is 2 kg/s. The mass-loss rate in trail particles is comparable to that inferred from OH production rates and larger than that inferred from visible-light scattering in comae.Comment: accepted by Icarus; figures compressed for astro-p

Comet 9P/Tempel 1: Interpretation with theDeep ImpactResults

“…(3) The existence of large compact dust in the preimpact T1 coma has been reported by many researchers (Sykes & Walker 1992;Farnham et al 2007;Reach, Kelley, & Sykes 2007). The existence of such large dust in the preimpact T1 is consistent with the standard model, because the dust mantle formation depletes only fluffy aggregates.…”

A dynamical model with a new inversion technique applied to observations of Comet C/2000 WM1 (LINEAR)☆

“…Thus, the observed anti-tail can possibly be considered as the inner part of a trail, a term usually used to describe the distribution of very large particles trailing behind the nucleus of short period comets (Sykes et al, 2004;Reach et al, 2007;Agarwal et al, 2007). Here we observe it in a long period comet.…”

2007 Outburst of 17p/Holmes: The Albedo and the Temperature of the Dust Grains

“…Moreno et al (2008) studied the morphology of the dust cloud in terms of the dynamics of the particles, and found that >600 μm particles, which are much less sensitive to radiation pressure than micrometersized or smaller particles, could be ejected by the outburst. Evidence of such large particles is found to be ubiquitous in in situ observations (McDonnell et al 1986;Tuzzolino et al 2003), by the remote sensing observations of dust tail (Fulle 2004;Moreno 2009;Watanabe et al 1990) and dust trail Ishiguro 2008;Sarugaku et al 2007;Reach et al 2000Reach et al , 2007Kelley et al 2008), sub-millimeter and millimeter observations (Jewitt & Matthews 1997;Altenhoff et al 1999). As a result of these studies, we found that the power index of the size distribution of almost all comets would be in the range of −4 and −3 (Fulle 2004).…”