We present spectra and high-resolution images taken with HST, the NTT, the VLA, and the MPIA/ESO 2.2m of the emission-line star He 3-1475 which we suggest is a post-AGB star. The star is presumed to be at the origin of a 15 00 long structure containing symmetrically opposing bright knots. The knots have radial velocities of 500 km s 1 from the center of He 3-1475 to the ends of the jets. HST snapshots show that the core of He 3-1475 is unipolar with a star at the SE end and the nebula fanning out toward the NW. VLA observations show the presence of OH masers, which are positioned parallel to the optical jets. A model is proposed that accounts for all of the observational data. This unusual object may link the OH/IR stars having extreme out ow velocities with highly bipolar planetary nebulae.

Abstract. We have selected 198 IRAS sources in the Large Magellanic Cloud, and 11 in the Small Magellanic Cloud, which are the best candidates to be mass-loosing AGB stars (or possibly post-AGB stars). We used the catalogues of Schwering & Israel (1990) and Reid et al. (1990). They are based on the IRAS pointed observations and have lower detection limits than the Point Source Catalogue. We also made cross-identifications between IRAS sources and optical catalogues.Our resulting catalogue is divided in 7 tables. Table 1 lists optically known red supergiants and AGB stars for which we found an IRAS counterpart (7 and 52 stars in the SMC and LMC, respectively). Table 2 lists "obscured" (or "cocoon") AGB stars or late-type supergiants which have been identified as such in previous works through their IRAS counterpart and JHKLM photometry (2 SMC and 34 LMC sources; no optical counterparts). Table 3 lists known planetary nebulae with an IRAS counterpart (4 SMC and 19 LMC PNe). Table 4 lists unidentified IRAS sources that we believe to be good AGB or post-AGB or PNe candidates (11 SMC and 198 LMC sources). Table 5 lists unidentified IRAS sources which could be any type of object (23 SMC and 121 LMC sources). Table 6 lists IRAS sources associated with foreground stars (29 SMC and 135 LMC stars). Table 7 lists ruled out IRAS sources associated with HII regions, hot stars, etc . . .We show that the sample of IRAS AGB stars in the Magellanic Clouds is very incomplete. Only AGB stars more luminous than typically 10 4 L and with a mass-loss rate larger than typically 5 10 −6 M /yr could be detected by the IRAS satellite. As a consequence, one expects to find very few carbon stars in the IRAS sample. We also expect that most AGB stars with intermediate mass-loss Send offprint requests to: loup at iap.fr rates have not been discovered yet, neither in optical surveys, nor in the IRAS survey.

We report the discovery of a symmetric bow shock around the well-known high-mass X-ray binary (HMXB) Vela X-1. Wind bow shocks are a ubiquitous phenomenon around OB-runaway stars, but now such a structure is found around a HMXB. The presence of a bow shock indicates that the system has a high (supersonic) velocity with respect to the interstellar medium. From the symmetry of the bow shock, the direction of motion and, moreover, the origin and age of the system can be derived. Our observation supports Blaauw's scenario for the formation of an OB-runaway star by the supernova explosion of the binary companion.

We present values for angular diameter, flux and extinction for 70 Galactic planetary nebulae observed using narrow‐band filters. Angular diameters are derived using constant emissivity shell and photoionization line emission models. The mean of the results from these two models are presented as our best estimate. Contour plots of 36 fully resolved objects are included and the low‐intensity contours often reveal an elliptical structure that is not always apparent from full width at half maximum measurements. Flux densities are determined, and for both Hα and [O iii] there is little evidence of any systematic differences between observed and catalogued values. Observed Hα extinction values are determined using observed Hα and catalogued radio fluxes. Hα extinction values are also derived from catalogued Hα and Hβ flux values by means of an RV dependent extinction law. RV is then calculated in terms of observed extinction values and catalogued Hα and Hβ flux values. Comparing observed and catalogue extinction values for a subset of bulge objects, observed values tend to be lower than catalogue values calculated with RV= 3.1. For the same subset we calculate 〈RV〉= 2.0, confirming that toward the bulge interstellar extinction is steeper than RV= 3.1. For the inner Galaxy, a relation with the higher supernova rate is suggested, and that the low‐density warm ionized medium is the site of the anomalous extinction. Low values of extinction are also derived using dust models with a turnover radius of 0.08 μm.

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