Other
Scientific paper
Jun 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006dda....37.1204t&link_type=abstract
American Astronomical Society, DDA meeting #37, #12.04; Bulletin of the American Astronomical Society, Vol. 38, p.673
Other
Scientific paper
The hierarchal triple system formed by the bright, nearby Cepheid Polaris, its visual companion (ADS 1477B), and recently resolved spectroscopic companion (ADS 1477Ab) at first sight seems well understood in terms of its astrometric properties: a parallax implying a distance of 132 +-8 pc (Hipparcos), and residuals implying an orbital inclination of 50 degrees (Wielen et al. 2000). But the recent optical detection of ADS 1477Ab by Evans et al. (2005) with the Hubble Space Telescope can be used to place independent constraints on the orbital properties of the system, once it is combined with the parameters of the spectroscopic orbit. To that end, existing radial velocity data for Polaris over the past 120 years, including previously-unpublished and recent observations obtained over the past two decades, have been collected, reanalyzed, and examined in order to improve the orbital parameters for the spectroscopic binary. There are small discrepancies in the data that may be linked to different sets of spectral lines and wavelength coverage used to infer the photospheric motion of the Cepheid, or to the inevitable problems of establishing reliable systemic velocities for a pulsating star. But the primary discrepancies lie in the implied properties of the Polaris system from the orbital solution, which seem to confirm the parallax of Polaris but not the orbital inclination, which may be edge-on. The results also conflict directly with other features of Polaris that are inferred from its other Cepheid characteristics: decreasing light amplitude, rapid period increase, location near the center of the instability strip, and possible membership in the Pleiades moving group. Such discrepancies are numerous enough to raise suspicions that there may be a fourth star in the system, although its detection may defy observers.
Klochkova Valentina G.
Miroshnichenko Anatoly S.
Panchuk Vladimir E.
Turner David G.
Usenko Iu. A.
No associations
LandOfFree
The Dynamical Challenges of the Polaris Multiple System 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 The Dynamical Challenges of the Polaris Multiple System, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Dynamical Challenges of the Polaris Multiple System will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1059028