Rosetta flyby of asteroid (21) Lutetia

On July 10, 2010 ESA's Rosetta spacecraft imaged asteroid Lutetia within an estimated distance of 3170 kilometers. Lutetia (the largest asteroid yet visited by a spacecraft) was discovered in 1852 from the Paris balcony of French painter turned astronomer Hermann Goldschmidt. To honour his home city, he called it 'Lutetia', after the Roman name for Paris.

In 2008 Rosetta encountered the asteroid (2867) Steins at a distance of 802.6 km.

All images: CREDIT: (C) ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

Pre-flyby image! View of Lutetia at a distance of 80,000 km.

Lutetia imaged just before its closest approach with Rosetta

At a distance of 36 000 km, Rosetta took this image of Lutetia with the planet Saturn in the background.

Lutetia close approach by Rosetta - Animation (click for a bigger version)

Next Rosetta rendezvous, scheduled for 2014, is with comet 67P/Churyumov-Gerasimenko. This comet rendezvous is the ultimate goal of Rosetta in the attempt to try to solve some of the enigmas of our Solar System.

by Ernesto Guido

Our last glance at comet 67P for a while

Periodic comet 67P/Churyumov-Gerasimenko, has greatly attracted the attention of the astronomical community, after the re-scheduling of the European Space Agency "Rosetta" mission toward it (http://www.esa.int/esaMI/Rosetta ).

After its perihelion passage, on February 28th, 2009, comet 67P has decreased its brightness, and moved toward solar conjunction. Currently it's observable again in Virgo. The main difficulty is due to its faintness (according to the ephemerids it's about m1= 19). On 2010 March 8th, we tried to perform some follow-up about this comet through the Grove Creek Observatory-Skylive network (near Trunkey, Australia). The sky conditions were good (stellar FWHM about 1.5 arcsec), with a stellar limiting magnitude on the final stacking close to 21.

At the expected coordinates, we found a faint (unfiltered CCD magnitude about 20.5) target that was and moving in good agreement with the ephemerids proper motion. In our stacking, it has a stellar aspect (details on image below. Click on the image for a bigger version):

According to the IAU-Minor Planet Center, "Dates Of Last Observation Of Comets", it was last observed on 2009 June 26, by the Observatorio Nazaret, of G. Muler (MPC#J47, Lanzarote, Spain).

Goodbye 67P, looking forward to you in May 2014, time of arrival of the Rosetta probe in yours vicinity.

by Giovanni Sostero & Ernesto Guido