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Observations of Galaxies with the Midcourse Space Experiment
We have imaged eight nearby spiral galaxies with the SPIRIT III infraredtelescope on the Midcourse Space Experiment (MSX) satellite in themid-infrared at 18" resolution at 8.3, 12.1, 14.7, and 21.3 μm. Eachof the eight shows interesting structure not previously detected witholder, lower resolution infrared data sets, such as a resolved nucleusor spiral structure. The MSX data are compared with existing data setsat ultraviolet, optical, and infrared wavelengths, including recentobservations from the Infrared Space Observatory. The infraredstructures in M83 and NGC 5055 show a striking similarity to theultraviolet emission but are less similar to the optical emission.Several point sources with no identified counterparts at otherwavelengths are found near M31, NGC 4945, M83, and M101. Over 200previously known objects are also detected at 8 μm.
| GPM1 - a catalog of absolute proper motions of stars with respect to galaxies
The description of the first version of the General Compiled Catalogueof Absolute Proper Motions (GPM1) for a sample of HIPPARCOS stars,derived with respect to galaxies within the plan called Catalogue ofFaint Stars (KSZ, Deutch 1952), is presented. The principal aim of theGPM1 construction was to provide absolute proper motions of stars todetermine the rotation of the HIPPARCOS system. The GPM1 cataloguecontains 977 HIPPARCOS Input Catalogue stars with V magnitudes $5^m -11^m in 180 fields north of -25 degrees of declination. The accuracy ofthe proper motions is 8 mas/yr (milliarcseconds per year). Comparison ofproper motions of GPM1 with those of the PPM and ACRS was performed andanalyzed with respect to systematic errors caused by spurious rotationof the FK5 system. The standard errors show that the rotation may bedetermined with an accuracy better than 1 mas/yr. Catalog is onlyavailable in electronic form at the CDS via anonymous ftpcdsarc.u-strasbg.fr or ftp 130.79.128.5.
| GPM - compiled catalogue of absolute proper motions of stars in selected areas of sky with galaxies.
Not Available
| A Deep X-Ray Image of M33
A 50.4 ks ROSAT Position Sensitive Proportional Counter image of thenearby spiral galaxy M33 reveals 37 sources within 15' of the nucleusbrighter than 7 x 10^35^ ergs s^-1^. There are at least 13 additionalsources farther from the nucleus, most of which are likely to beassociated with M33 as well. Most of the bright sources that had beendetected with Einstein in the same region are still visible. The bulk ofthe sources in the galaxy are associated with Population I tracers.Several of the sources are time variable. There are 10 sources in theimage that lie within 20" of optically identified supernova remnants(SNRs) in M33. The spectra of these sources are soft compared with mostother sources of comparable brightness, and therefore it is likely thatmost of these X-ray sources are SNRs. Based on the identification ofsources in M33, it appears likely that ROSAT hardness ratios of thistype can be used to separate SNRs and compact sources in other nearbynormal galaxies as well. The northern and the southern spiral arms ofM33 appear as diffuse features in the X-ray image. There is additionaldiffuse (or unresolved source) emission throughout the inner portions ofM33. The diffuse emission is softer than the faint point sources and theSNRs in the survey, and is well fitted in terms of a bremsstrahlungspectrum with kT ~ 0.4 keV and log N_H_ ~ 20.6.
| The galactic foreground reddening in the direction of the nearby triangulum galaxy M33
Observations of 314 stars with the uvby-beta photometric system are usedto establish the reddening in the direction of the nearby Triangulumgalaxy M33. Color excesses are obtained for 151 A and F type stars in a1 deg radius centered around the galaxy. A color excess of E(b-y) =0.057 mag /E(B-V) = 0.077 mag/ is obtained for a distance modulus m - M= 10. A secondary result of this investigation is the discovery of sixsuspected variable stars, as well as ten observations of V Triangulum, aBeta Lyrae eclipsing variable.
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| Takýmyýldýz: | Ucgen |
| Sað Açýklýk: | 01h35m25.98s |
| Yükselim: | +30°46'30.6" |
| Görünürdeki Parlaklýk: | 8.084 |
| Uzaklýk: | 389.105 parsek |
| özdevim Sað Açýklýk: | 21.5 |
| özdevim Yükselim: | -8.5 |
| B-T magnitude: | 10.171 |
| V-T magnitude: | 8.257 |
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