Volume 524, December 2010
|Number of page(s)||1|
|Section||Planets and planetary systems|
|Published online||19 November 2010|
The activity of comet C/2007 D1 (LINEAR) at 9.7 AU from the Sun ⋆ (Corrigendum)
INAF–Osservatorio Astronomico di Capodimonte, via Moiariello 16, 80131
2 Fundación Galileo Galilei - INAF, Rambla José Ana Fernández Pérez, 7, 38712 Breña Baja, TF, Spain
3 Instituto de Astrofísica de Canarias, c/vía Láctea s/n, 38200 La Laguna, Tenerife, Spain
4 Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain
5 Universitá Parthenope, Dip. Scienze Applicate, Centro Direzionale Isola C4, 80143 Napoli, Italy
Key words: comets: individual: c/2007 D1 (LINEAR) / errata, addenda
We report the discovery of an incoherence while describing the results of modelling the dust mass-loss rate of comet C/2007 D1 (LINEAR). The code of the tool is correct, but while saying in Sect. 3 that we adopt the classical “cometary” values of geometrical albedo A = 0.04 and phase coefficient β = 0.045 mag/°, we erroneously use different values of both parameters (derived from different assumptions and formalisms: A = β = 0.1 as in Jewitt 2009) in the calculation. This propagates in the actual values of dust cross-section, dust mass in the coma annulus, and dust mass-loss rate. The table reported in this Corrigendum replaces Table 2 published in the original paper. Below we report how the final part of last paragraph of Sect. 3 (observational results) and central paragraph of Sect. 4 (discussion and conclusions) should be read. Our conclusions on the intense post-perihelion activity of comet C/2007 D1 are even strengthened by these new calculations.
Model dust mass-loss rate of comet C/2007 D1 (LINEAR).
Adopting then a more realistic dust grain velocity v(r) ~ 50 m s-1, a value of kg s-1 is obtained from the photometric model. Table 1 summarises the values derived for all the quantities defined above, for both the realistic value and the upper limit (gas ouflow) of the dust grain velocity.
The first-order photometric model (Jewitt 2009) for determining of the dust-loss rate that we applied to the images, by using a realistic value for the dust grain velocity (see above), inferred a very high value of kg s-1. This value is indicative of a very active comet, similar to (if not more active than) the “paradigm” comet C/1995 O1 (Hale-Bopp), for which a kg s-1 was obtained by modelling at r = 13 AU (Fulle et al. 1998). For comparison, by applying the first-order photometric model to the active Centaur 29P/S-W1 at r = 5.8 AU, Jewitt (2009) obtained a dust production rate of kg s-1, while the application of the inverse tail model by Fulle (1992), which reconstructed the dynamical dust environment (ejection velocity, dust-loss rate, and reliable dust-grain size distribution) of the Centaur, resulted in a constant value of the dust production rate of 6 × 102 kg s-1 during the three years spent by the Centaur at about the same heliocentric distance. To a first-order approximation, if we apply the same scaling factor to the upper limit to the dust-loss rate (, see Table 1), we would obtain a dust-loss rate of ~1100 kg s-1 for comet C/2007 D1, which is very similar to the value obtained using the photometric model with realistic velocity value.
© ESO, 2010
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.