Multispectral Light Curves of Vesta

Details Multispectral Light Curves of Vesta Multispectral Light Curves of Vesta

Jan 1996

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1996eiaf.conf...13j&link_type=abstract

Workshop on Evolution of Igneous Asteroids: Focus on Vesta and the HED Meterorites, p. 13

Computer Science

1

Vesta Asteroid, Photometry, Absorption Spectra, European Southern Observatory, Synthetic Apertures, Ccd Cameras, Spectrophotometry

Scientific paper

In order to characterize its compositional heterogeneity we have carried out time-resolved CCD spectrophotometry of 4 Vesta during its last apparition in 1996. The observations have been performed from the European Southern Observatory (La Silla, Chile), with the DLR CCD camera attached at the Bochum 24" telescope using a set of five interference filters covering the spectral range 0.45-0.95 pm. In order to obtain the high photometric accuracy necessary to reveal subtle color variations, we have performed on-chip differential photometry against a field star, which allows effective correction for short-term atmospheric extinction fluctuations. The observations were therefore carefully planned and scheduled for one night when 4 Vesta was passing close to a bright star (SAO 140637). Measurements in each filter were automatically cycled over about 5 hr, in order to fully cover an asteroid's rotational period. Only the small portion of the CCD actually containing 4 Vesta and the comparison star was read out, which allowed us to have a very fast duty cycle of about 90 s. A GO-type star (BS 5779) located less than 2 degrees from the Vesta field was acquired during its passage at meridian, in order to provide reflectance calibration. The resulting dataset of approximately 1000 frames was preprocessed using bias frames and twilight sky flat fields, while photometry was computed by using ASTPHOT, a synthetic aperture program developed at DLR. Extinction correction was derived directly by dividing the flux of the asteroid by the on-field comparison star, while higher-order, differential extinction coefficients were neglected due to the comparatively narrow bandwidth of the filters used.

Affiliated with

Also associated with

No associations

Rating

Multispectral Light Curves of Vesta does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Multispectral Light Curves of Vesta, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multispectral Light Curves of Vesta will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-970316