Hipparcos: Light Curves for Unsolved Variables
The light curves here are taken from Volume 12: Part C of The Hipparcos and Tycho Catalogues. This contains light curves extending over the entire Hipparcos mission duration for non-periodic variable stars. Although no period has yet been found for these objects, it is expected that - in many cases - by following up their observations from the ground, their variability type, and perhaps their periods, may be established. This is most obvious in the case of eclipsing binary systems, where a dramatic dip in the intensity of the star indicates the occultation of one star by another in a binary system. Now that these systems have been identified as eclipsing, they can be monitored with greater intensity in anticpation of detecting a future minimum. Once this is done, the period can be determined, and future minima predicted.
Click on the HIP number of the star to return the Hipparcos Catalogue entry and further links for the star. Although none of these objects has a period determined from the Hipparcos observations, some of them are periodic. If you make new observations, you could add your new data into the existing epoch photometry file, and experiment with new period fits using the Hipparcos data in combination with your own data.
Data for all 11800 Hipparcos stars is available on Disk 2 of Volume 17, as file hip_ep.dat. The data format used corresponds to that of the Epoch Photometry Annex contained in the published Hipparcos Catalogue and described in Section 2.5 of Volume 1 of the catalogues. The individual epoch photometry transit records (Fields HT1-4; accessible through the hyperlinks on this page) are preceded by a header record (Fields HH1-4). For each transit the observation epoch is given as Field HT1 in the table. The calibrated Hipparcos magnitude and estimated standard error are given in Fields HT2 and HT3 respectively.