We present an analysis of the optical spectroscopy of 58 stars in the Galactic plane at l=27deg, where a prominent excess in the flux distribution and star counts have been observed in several spectral regions, in particular in the Two-Micron Galactic Survey (TMGS) catalog. The sources were selected from the TMGS to have a K magnitude brighter than +5mag and to be within 2deg of the Galactic plane. More than 60% of the spectra correspond to stars of luminosity class I, and a significant proportion of the remainder are very late and fast-evolving giants. This very high concentration of young sources points to the existence of a major star formation region in the Galactic plane, located just inside the assumed origin of the Scutum spiral arm. Such regions can form because of the concentrations of shocked gas where a galactic bar meets a spiral arm, as is observed at the ends of the bars of face-on external galaxies. Thus, the presence of a massive star formation region is very strong supporting evidence for the presence of a bar in our Galaxy.
Using Hubble Space Telescope Fine Guidance Sensor astrometry and previously published radial velocity measures, we explore the exoplanetary system HD202206. Our modeling results in a parallax, {pi}_abs_=21.96+/-0.12 milliseconds of arc, a mass for HD202206B of M_B_=0.089_-0.006_^+0.007M_{Sun}_, and a mass for HD202206c of M_c_=17.9_-1.8_^+2.9^M_Jup_. HD202206 is a nearly face-on G + M binary orbited by a brown dwarf. The system architecture that we determine supports past assertions that stability requires a 5:1 mean motion resonance (we find a period ratio, P_c_/P_B_=4.92+/-0.04) and coplanarity (we find a mutual inclination, {Phi}=6{deg}+/-2{deg}).
The fifth annual catalog of the Tokyo PMC is presented for 3466 stars (Part I and Part II) which were observed at least two times in the 1989 period, that is, from January 1, 1989, to December 31, 1989. The positions of the stars given in the catalog are those at the mean epoch of observations. The coordinates of the catalog are based on the FK5 system, and refer to the equinox and equator of J2000.0. The values of (O-C)s in the catalog are calculated by using the positions given in the source catalog, and by evaluating those at the mean epoch of observations of each star, with the equinox and equator at the mean epoch. The magnitudes of the stars given in the catalog can be transformed into the V-magnitude of the standard UBV system by the equation: V = V(TPMC) + 0.063 ( B-V ) - 0.045. The mean trends of the observed positions-FK5 positions for the basic FK5 stars are constructed and compared with those of the Tokyo PMC Catalogs 86, 87, and 88. The Part I of the catalog contains the positions of 1080 basic FK5 stars, 210 FK4 Suppl. stars, 1700 AGK3R stars, 131 OB stars, 36 NPZT stars, and 96 SAO stars, observed with the Tokyo PMC in the 1989 period based on FK5 system. The Part II of the catalog contains the positions of 210 zodiacal stars observed with the Tokyo PMC in the 1989 period based on the FK5 system. The stars of the Part II are usable for the reduction of lunar occultation. The Parts I and II are concatenated to form a single machine-readable catalog.
The third annual catalog of the Tokyo PMC is presented for 5748 stars which had been observed at least two times in the year 1987 period, that is, from January 1, 1987, to December 31, 1987. The positions of the stars given in the catalog are those at the mean epoch of observations. The coordinates of the catalog are referred to the equinox and equator of J2000.0, based on the FK5 system. The mean trends of the observed positions minus FK5 positions for the FK5 basics stars are constructed and compared with those of the Tokyo PMC 86 catalog. The part I of the catalog contains the positions of 1017 FK5 basics (=FK4 stars ), 533 FK4 Suppl. stars, 2421 AGK3R stars, 1167 OB stars, 113 NPZT stars, and 84 SAO stars, and the part II of the catalog contains the positions of 413 SAO stars for occultation studies. These two parts were merged into a single pmc87 file.
The catalog of positions of 1007 stars (792 FK4 and FK4S stars, 57 OB stars, 49 NPZT stars, and 109 SAO stars) is presented. They were observed during the period from December 1984 to September 1985 with the Tokyo Photoelectric Meridian Circle (Tokyo PMC). The positions in the catalog are referred to the equinox and equator of J2000, and are based on the FK4 system. The internal errors of a single observation were estimated to be (epsilon(alpha)*cos(delta), epsilon(delta)) = (0.16", 0.19"), whereas the mean internal errors of the catalog positions were (0.08", 0.08") for FK4 stars and (0.09", 0.11") for FK4S stars. The comparison of the positions of the FK4 stars in the present catalog with those of the FK4 catalog shows the significant differences delta(alpha(delta)) and delta(delta(delta)) in some declination zones. Some of those differences are commonly found in other recent catalogs. Thus they may be considered to be the real systematic errors in the FK4 system. Neither significant magnitude nor color equation exists in the Tokyo PMC85 catalog.
The second annual catalog of the Tokyo Photoelectric Meridian Circle contains 3974 stars that were observed at least twice between 21 December 1985 and 31 December 1986. Specifically, it contains 1141 FK5 stars, 971 FK4 supplemental stars, 554 AGK3R stars, 403 OB stars, 421 NPZT stars, and 484 SAO stars. The positions are for the mean epoch of observation referred to the equinox and equator of J2000.0 and based on the FK5 system. The internal error of a single observation for the bright stars is 0.24" and 0.27" in right ascension and declination, respectively. The catalog contains, in addition to the positions, the catalog from which the star is taken and the number in that catalog, the mean epoch and number of observations of each component of the position and of the magnitude, the spectral type, the V magnitude, and the DM and AGK3 numbers. It also contains the residuals between the position in this catalog and that in the source catalog and mean errors for each component of the position and of the magnitude.
The sixth annual catalog of the Tokyo PMC is presented for 6649 stars which were observed at least two times in January 1990 through March 1993. The mean positions of the stars observed in the above period are given in the catalog at the corresponding mean epochs of observations of individual stars. The coordinates of the catalog are based on the FK5 system, and referred to the equinox and equator of J2000.0. The mean local deviations of the observed positions from the FK5 catalog positions are constructed for the basic FK5 stars to compare with those of the Tokyo PMC Catalog 89 and preliminary Hipparcos results of H30. The catalog contains the positions of 1180 basic FK5 stars, 322 FK4 Suppl. stars, 3132 AGK3R stars, 141 OB stars, 252 NPZT stars, and 1601 SAO stars observed with the Tokyo Photoelectric Meridian Circle in the 1990 to 1993 periods based on the FK5 system. The positions of the stars are given for the mean epoch of the observations of individual stars referring to the equinox and equator of J2000.0. The values of (O-C)s in the catalog are calculated by using the positions given in the source catalog, and by evaluating those at the mean epoch of observations of each star, with the equinox and equator at the mean epoch. The magnitudes of the stars given in the catalog can be transformed into the V-magnitude of the standard UBV system by the equation : V = V(TPMC) + 0.063(B-V) - 0.045.
The fourth annual catalog of the Tokyo PMC is presented for 3800 stars (Part I and Part II) which had been observed at least two times in the 1988 period, that is, from January 1, 1988, to December 31, 1988. The positions of the stars given in the catalog are those at the mean epoch of observations. The coordinates of the catalog are based on the FK5 system, and are referred to the equinox and equator of J2000.0. The positions of five major and nine minor planets are also given in the present catalog (Part III) for all individual observations made in 1986 to 1988. The planetary positions are based on the same coordinate systems as those of the corresponding annual star catalogs, the Tokyo PMC Catalogs 86, 87, and 88. The mean trends of the observed positions - FK5 positions for the basic FK5 stars are constructed and compared with those of the Tokyo PMC Catalogs 86 and 87. As for the planets, their observed positions are compared with the positions of the JPL's planetary ephemeris DE200. We find that the ephemerides of the outermost planets, Uranus and Neptune, have some systematic deviations of a few tenths of arcsec in longitudes.
Catalog of 90 astrometric positions of Pluto have been compiled with Tycho-2 as a reference frame from photographic observations obtained at the Main Astronomical Observatory, National Academy of Sciences of Ukraine, Astronomical Observatory of the Kyiv Shevchenko National University, Research Institute Mykolaiv Astronomical Observatory and Baldone Observatory of the University of Latvia in 1961-1996. Astronegatives have been digitized with Epson Perfection V750 Pro and Epson Expression 10000XL commercial scanners in 16-bit grayscale with a resolution of 1200 dpi. (O-C) residuals obtained from the comparison with JPL PLU055/DE433 ephemeris are 0.09 ... 0.14 arcsec. Gallery of plate images used for catalog: http://gua.db.ukr-vo.org/catalog_gallery.php?catn=pluton_1961_1996
A catalog of 1399 astrometric positions of Saturn's moons S2-S9 has been compiled with Tycho-2 as a reference frame from photographic observations obtained at the Main Astronomical Observatory, National Academy of Sciences of Ukraine, in 1961-1990. Astronegatives have been digitized with an Epson Expression 10000XL commercial scanner in 16-bit grayscale with a resolution of 1200 dpi. Reduction has been performed in the LINUX-MIDAS-ROMAFOT software supplemented with additional modules. The internal positional accuracy of the reduction is 0.09...0.23" for both coordinates and 0.27...0.37m for the photographic magnitudes of the Tycho-2 catalog. Gallery of plate images used for the catalog: http://gua.db.ukr-vo.org/catalog_gallery.php?catn=satmoons_1961_1990
