2024-03-29T14:06:40Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/71492016-02-16T03:40:27Zcom_10261_97com_10261_4col_10261_476
The Light Curve Of The Dust Cloud Ejected By The Collision Between The Deep Impact Projectile And The Nucleus Of Comet 9P/Tempel 1
Küppers, Michael
Rengel, Miriam
Keller, H.U.
Gutiérrez, Pedro J.
Hviid, Stubbe F.
Astrophysics
Comet 9P/Tempel 1
Deep Impact spacecraft
Projectile impact
Dust cloud
Light curve
Velocity distribution
Narrow Angle Camera (NAC)
Rosetta spacecraft
OSIRIS
Contribution presented at the 39th Annual Meeting of the Division for Planetary Sciences of the American Astronomical Association (DPS 2007), October 7-12, 2007 Orlando, Florida.
When Deep Impact fired its projectile into the nucleus of comet 9P/Tempel 1, a cloud made of dust and icy grains was ejected from the impact crater. The dust was subsequently accelerated by gas drag. About a week after the impact event, the dust cloud has dispersed due to its expansion and the force exerted by solar radiation pressure. The light curve of the dust cloud contains information about its formation and evolution: the time scale of the production of impact created material can be derived from the time scale of the brightness increase. The velocity distribution of the cloud is indicative of acceleration processes in the inner coma of the comet. Finally, the abundance of large dust particles created by the impact can be estimated from the brightness of the cloud several days after the impact when small particles have been pushed away by radiation pressure.
Here we analyze data obtained by the Narrow Angle Camera (NAC) of OSIRIS onboard the ESA spacecraft Rosetta to derive the velocity distribution of the dust cloud from an inversion of its light curve. OSIRIS observed comet Tempel 1 near-continuously for more than two weeks around the impact. A model of the expansion of the ejecta is compared to the light curve seen by the NAC. We derive a broad velocity distribution of the dust particles, which peaks at around 225 m/s, in good agreement with published estimates. The velocity suggest that the impact ejecta were quickly accelerated by gas in the cometary coma. We will discuss implications of our results for the evolution of the dust cloud during the first hours after the impact and provide estimates of the released dust mass.
2008-09-10T11:16:11Z
2008-09-10T11:16:11Z
2007-10
póster de congreso
39th Annual Meeting of the Division for Planetary Sciences of the American Astronomical Association (DPS 2007)
http://hdl.handle.net/10261/7149
eng
openAccess
AAS Division of Planetary Sciences