Contenidos
Imágenes
Subir su imagen
DSS Images Other Images
Artículos relacionados
The Milton Bureau Revisited
Under the direction of Cecilia Payne-Gaposchkin and Sergei Gaposchkin, aprogram was subsidized by the Milton Fund of Harvard Observatory in 1937for the study of all variable stars then known to be brighter than tenthphotographic magnitude at maximum. This included some 1512 stars forwhich a grand total of 1,263,562 estimates of magnitude were made,ranging from a low of 16 (except for a few novae) to 4084 observationsper star. The sky had been divided into 54 fields, and the results ofthe measurements presented field by field in two volumes of the Annalsof Harvard Observatory. Then, in another volume, the results werediscussed in four sections, each dealing with a particular class ofvariable: 1, those of RV Tauri type; 2, the eclipsing variables; 3,Cepheids and RR Lyrae variables, and 4, the red variables, especiallyMira-type and semiregular variables.For the present paper, many of these results have been compared withmodern determinations in the 1985-87 version of the "General Catalogueof Variable Stars (GCVS)". In particular, there are numerous instancesof disagreement as to whether a star should be classified RV or SR.Although there are many instances where the Milton Bureau determinationsof types of variability differ from the types given in moderncatalogues, the reasons for the differences are generallyunderstandable.For 17 RV Tauri type stars in this survey multiple periods have now beendetermined. Many of these still deserve continued observations in orderto ascertain the constance of the periods and improve the accuracy oftheir longest reported periods.
| The Program to Link the HIPPARCOS Reference Frame to an Extragalactic Reference System Using the Fine Guidance Sensors of the Hubble Space Telescope
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.2796H&db_key=AST
| Stars Classified as Constant in the General Catalogue of Variable Stars, II
Photometric observations have been made of 36 stars classified as CST orCST: in the General Catalogue of Variable Stars. Six of these stars arefound to vary and three others were deemed possible variables. Of thecertain variables, two (MR Her and TY Sge) are red pulsators, one (V1585Cyg) is a rapid irregular variable, one is apparently a short periodCepheid-strip star (V432 Oph), one is an eclipsing binary (AQ Boo) andone is uncertain type (V351 Cyg). The stars we have observed as MR Herand TY Sge are the same ones which were identified on finding charts inthe discovery papers suggesting that these stars have intervals ofvariability and intervals of quiescence. V432 Oph is of special interestbecause our photometry indicates that it may be either a double modeCepheid or a peculiar long period RR Lyrae star depending on which of acouple of possible periods turns out to be correct. (SECTION: Stars)
| Stromgren Photometry of UU Her: 1987 Results
Not Available
| Multisite observations of UU Herculis - 1985 results
The results of a joint effort to monitor photometrically the remarkablevariable star UU Her from four observatories in Europe and North Americaare presented. UU Her is known to exhibit two distinct pulsationalmodes. During 1984 - 85 the amplitude of the pulsations increased andthere seemed to be a change in the V, (B-V) phase shift from negative in1984 to positive in 1985. Meanwhile, there was no discernible change inthe pulsational period or the shape of the light curve. High-dispersionspectra of UU Her from 3500 Å to 6900 Å were also obtained.There are no obvious traces of mass loss or shell phenomena in itsoptical spectrum. The status of UU Her remains unclear.
| Electrophotometric observations of UU Herculis.
Electrophotometric observations of the semi-regular variable UU Her aregiven. These observations have been obtained by the author in 1985. Theperiod of 80 days is determined surely. The curve of colour index B-V iscoincident in phase with the light curve. According to the light curveshape of UU Her the star can be referred both to RV Tau-type variablesand to classical Cepheids that makes further observations urgent.
| Photoelectric Minima of Eclipsing Variables
Not Available
| A Spectroscopic Study of the RR Lyrae Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJ...130..507P&db_key=AST
| Mitteilungen über veränderliche und verdächtige Sterne
Not Available
|
Enviar un nuevo artículo
Enlaces relacionados
- - No se han encontrado enlaces -
En viar un nuevo enlace
Miembro de los siguientes grupos:
|
Datos observacionales y astrométricos
| Constelación: | Hércules |
| Ascensión Recta: | 16h34m34.92s |
| Declinación: | +37°59'44.2" |
| Magnitud Aparente: | 8.871 |
| Distancia: | 113.379 parsecs |
| Movimiento Propio en Ascensión Recta: | -19.3 |
| Movimiento Propio en Declinación: | -13.4 |
| B-T magnitude: | 9.365 |
| V-T magnitude: | 8.912 |
Catálogos y designaciones:
|
