תוכן
תמונות
הוסף תמונה שלך
DSS Images Other Images
מאמרים קשורים
IRAS spectra planetary nebulae. III
Measurements of the IRAS spectra of planetary nebulae are presented. Thespectra cover the wavelength 7.5 to 23 microns. The lines observed aremainly from ions of neon and sulfur. The abundance of these two elementsis determined and compared to results found in other astronomicalobjects. It is also found that the Ne(4+) ion, when present, is formedin a region whose density is an order of magnitude higher than theregion whose density is an order of magnitude higher than the regionwhere most of the line emission originates. IUE measurements of theNe(3+) line of many of the nebulae are presented.
| Four-colour and H-beta photometry of B stars in Fehrenbach and Burnage radial velocity fields at B about -30 deg
Observations in uvby and H-beta are presented for 39 stars classified asB-type in seven 4 x 4-deg fields studied by Fehrenbach and Burnage(1981, 1982) at b about -30 deg. About half the stars arephotometrically little-evolved B stars; most of the rest areintermediate A stars. Intrinsic color and absolute-magnitudecalibrations are applied: that of Hilditch et al. (1983) forintermediate A stars is estimated to be much less certain than those forother types. Maps of reddening along lines of sight indicate that littlereddening occurs within 100 pc of the sun, that essentially allreddening has occurred within z = + or - 150-200 pc, and that the totalreddening is essentially consistent with values given by the Bursteinand Heiles (1982) HI/GC method. The luminosities of some faint early Bstars cannot be usefully constrained by placing them within thereddening structure. One of the two program stars with very large radialvelocities is a horizontal branch object; the other has peculiar colors.
| A new list of 617 radial velocities in four galactic fields
Four stellar fields in the -30 deg galactic latitude have been surveyedfor radial velocities, using a 62 cm objective prism. Exact positions,spectral types, and approximate magnitudes are provided for 617 stars infour different 4 x 4 deg fields. B to F4 stars were found which haveGaussian velocity distributions.
|
הכנס מאמר חדש
לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
|
תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | אנדרומדה |
| התרוממות ימנית: | 00h18m00.88s |
| סירוב: | +31°17'30.6" |
| גודל גלוי: | 8.286 |
| מרחק: | 458.716 פארסק |
| תנועה נכונה: | -1 |
| תנועה נכונה: | -4.7 |
| B-T magnitude: | 8.345 |
| V-T magnitude: | 8.291 |
קטלוגים וכינוים:
|
