Visual Orbit Solutions from Observing Techniques Old and New.

摘要

For the past couple of decades, the primary double star observational technique utilized at the US Naval Observatory has been speckle interferometry. Our two speckle cameras have been used on a variety of telescopes: our 26' in Washington, the USNO (NOFS) 61', the McDonald 82', the Mt. Wilson 100' and the twin 4 meter telescopes of KPNO and CTIO. While these instruments have each yielded many observations, they have been involved in rather different programs, with the 26' observing primarily the so-called 'neglected' pairs and larger instruments conducting duplicity surveys and observing close, astrophysically interesting systems. While speckle is quite successful at resolving relatively close pairs, for those pairs which are both bright and very close long baseline optical interferometry may be the only viable solution. Utilizing both the CHARA Array and the Navy Prototype Optical Interferometer, numerous hard-to-observe pairs first resolved by speckle have been observed using these arrays' superior resolution capabilities; this has allowed these orbits to be significantly improved; examples of pairs observed by each of these instruments are presented. At the other separation extreme, a cache of photographic plates taken with the USNO double star camera has been digitized and processed. Some 66 plates of Sirius A and B taken between 1970 and 1984, which represents a 10% increase in the total number of measures, have been reduced, enabling a significant improvement over the current 'best' Sirius orbit, almost one full revolution later.