Ýçindekiler
Görüntüler
Resim Yükleyin
DSS Images Other Images
Ýlgili Makaleler
Study of Molecular Clouds and Star Formation in the Region of IC 2118 We carried out a12CO survey of molecular clouds in the regionof the reflection nebula IC 2118. Our observations covered the wholearea of IC 2118 (~ 6 deg2) with a 2'.6 beam at a 4' gridspacing. We identified six molecular clouds. Based on a literaturesearch we found a distance value of 210 pc for the reflection nebula andits associated molecular clouds, indicating that the clouds are probablyinteracting with the Orion--Eridanus Bubble. Using this distance value,we determined the physical properties of the clouds. We also made anobjective prism search for Hα emission stars in the region inorder to find possible solar-type stars born in the clouds, andidentified 46 candidate pre-main-sequence stars. Their spectroscopicfollow-up is in progress. Seven of them have so far proved to be T Tauristars.
| UBV absolute CCD photometry and differential astrometry of a sample of visual double stars with A-type primaries We present V magnitudes, (B-V) and (U-B) colours of the components of111 visual double stars and their relative position measurements rho andtheta . The primaries are of spectral class A; the angular separation isin the 2farcs5 -8arcsec range. The observations were made at the 61-cmreflector of University of Toronto Southern Observatory, Chile. Theobtained photometric results are of a moderate quality for absolutevalues (0.04() m (mag) in V and about 0.02() m in the (B-V) and (U-B)colour indices) and more precise in Delta V and Delta (U-B), Delta (B-V)(0.023() m and 0.015() m, respectively). We find that about 60% ofsecondaries are also of spectral type A; 56% of pairs have Delta (B-V)less than 0.1() m. The two-colour diagram reveals significant offset ofobjects from the curve of unreddened Main Sequence stars. Acomprehensive survey of stars in the close vicinity to the objects isalso presented. The final astrometric accuracy of ~ 0farcs01 in rho and0fdg1 in theta provides additional measurements for study of relativemotion of the components. Based on observations made at University ofToronto Southern Observatory, Las Campanas, Chile. Tables\arabic{tabptm}--\arabic{tabast} are only available in electronic format the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) orvia http://cdsweb.u-strasbg.fr/Abstract.html
| A preliminary compilation of DS-programme star positions A catalog is presented of the double-star-program (DS-program) starpositions, listing right ascensions for 930 DSs and declinations for1225 DSs of the program. The positions were compiled from the observedvalues obtained between 1980 and 1987 with the meridian circles of sixUSSR observatories (the Moscow, Kazan', Kiev, Khar'kov, Odessa, andTashkent Observatories) and the Belgrade Observatory. The measurementsand the treatment of the observational material were performed using therelative method, and the FK-4 system stars were used as reference stars.
| Stromgren and H-beta photometry of stars earlier than G0 in 5 areas containing high latitude molecular clouds Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1989A&AS...80..127F&db_key=AST
| Visual multiples. VII - MK classifications Classifications are given for 865 components of visual multiples; theyshow no systematic differences from the MK system, and the random errorsare one subclass in type and two-thirds of a luminosity class. It isfound that at least 1% of the F-type IV and V stars are weak-lined, 32%of the A4-F1 IV and V stars are Am, and 5% of the A0-A3 IV and V starsare early-type Am. Attention is called to the large fraction (55%) ofthe A3-A9 III-V stars that are of luminosity classes III or IV, unlikethe percentage (16%) at neighboring types.
| Photovisual differences in magnitudes of 331 mainly southern double stars Not Available
|
Yeni bir Makale Öner
Ýlgili Baðlantýlar
Yeni Bir Baðlantý Öner
sonraki gruplarýn üyesi:
|
Gözlemler ve gökölçümü verileri
Takýmyýldýz: | Irmak |
Sað Açýklýk: | 05h03m01.95s |
Yükselim: | -08°39'47.4" |
Görünürdeki Parlaklýk: | 7.113 |
Uzaklýk: | 151.057 parsek |
özdevim Sað Açýklýk: | -23.7 |
özdevim Yükselim: | -6.1 |
B-T magnitude: | 7.02 |
V-T magnitude: | 7.106 |
Kataloglar ve belirtme:
|