This paper aims to evaluate the background of known asteroids present in the field of the Wide Angle Camera (WAC) of the Rosetta Mission during the flybys of (4979)Otawara and (140)Siwa. The field of view (FoV) is very wide, namely 12x12 sqdeg, and the limiting magnitude in the R filter in 60 seconds is around the 10th; therefore the possibility of asteroids being in the image are not negligible. In order to determine the objects present in the FoV a program has been developed to derive the rectangular ecliptic coordinates of all numbered asteroids (27654 derived from MPC database). The same coordinates for the spacecraft were kindly provided by ESOC. The calculations have been extended from the 7th till the 13th of July 2006 for the Otawara flyby, and from the 18th till the 26th of July 2008 for the Siwa flyby. We have identified 11 objects till the 13th magnitude which will be present in WAC's FoV during Otawara flyby (2 till 11th magnitude) and 12 objects during Siwa flyby (1 till 11th magnitude). In the near future we plan to extend our search to all known asteroids (even non numbered ones) provided by MPC database. This work has been partly supported by the Italian Space Agency (ASI)
Asteroidal background for the Wide Angle Camera of the Rosetta Mission
Bertini, I.
2001-01-01
Abstract
This paper aims to evaluate the background of known asteroids present in the field of the Wide Angle Camera (WAC) of the Rosetta Mission during the flybys of (4979)Otawara and (140)Siwa. The field of view (FoV) is very wide, namely 12x12 sqdeg, and the limiting magnitude in the R filter in 60 seconds is around the 10th; therefore the possibility of asteroids being in the image are not negligible. In order to determine the objects present in the FoV a program has been developed to derive the rectangular ecliptic coordinates of all numbered asteroids (27654 derived from MPC database). The same coordinates for the spacecraft were kindly provided by ESOC. The calculations have been extended from the 7th till the 13th of July 2006 for the Otawara flyby, and from the 18th till the 26th of July 2008 for the Siwa flyby. We have identified 11 objects till the 13th magnitude which will be present in WAC's FoV during Otawara flyby (2 till 11th magnitude) and 12 objects during Siwa flyby (1 till 11th magnitude). In the near future we plan to extend our search to all known asteroids (even non numbered ones) provided by MPC database. This work has been partly supported by the Italian Space Agency (ASI)I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
