A high resolution optical spectrum of the postred supergiant candidate IRC+10420 is presented. The Utrecht Echelle Spectrograph observations, with a total integration time of more than 9 hours, provide a spectral coverage from 3850Å to 1 µm, and a spectral resolution of 9 km s −1 . The spectrum is shown, and an identification list of lines in the spectrum is provided. From a preliminary analysis of the spectrum we find that the spectral type of IRC+10420 has changed from F8I + in 1973 to midto early A type now, confirming the results of Oudmaijer et al. (1996), who claimed a change in temperature based on photometric changes. It is shown that most of the emission lines in the spectrum of IRC+10420 are blue-shifted with respect to the systemic velocity traced by circumstellar rotational CO emission, while the (few) absorption lines -with the exception of some high excitation linesare red-shifted by 25 km s −1 , which may suggest infall of material onto the star. Finally, it is found that the interstellar extinction towards IRC+10420 as traced by the Diffuse Interstellar Bands is very large, with an inferred E(B-V) of 1.4 ± 0.5 compared to a total E(B-V) of 2.4.

The theoretical prediction that trigonometric parallaxes suffer from a statistical effect, has become topical again now that the results of the Hipparcos satellite have become available. This statistical effect, the so-called Lutz-Kelker bias, causes measured parallaxes to be too large. This has the implication that inferred distances, and hence inferred luminosities are too small. Published analytic calculations of the Lutz-Kelker bias indicate that the inferred luminosity of an object is, on average, 30% too small when the error in the parallax is only 17.5%. Yet, this bias has never been determined empirically. In this paper we investigate whether there is such a bias by comparing the best Hipparcos parallaxes which ground-based measurements. We find that there is indeed a large bias affecting parallaxes, with an average and scatter comparable to predictions. We propose a simple method to correct for the LK bias, and apply it successfully to a sub-sample of our stars. We then analyze the sample of 26 `best' Cepheids used by Feast & Catchpole (1997) to derive the zero-point of the fundamental mode pulsators and leads to a distance modulus to the Large Magellanic Cloud - based on Cepheid parallaxes- of 18.56 +/- 0.08, consistent with previous estimates.Comment: MNRAS Letters in press; 6 pages LaTeX, 6 ps figure

Abstract. We present near-IR JHK photometric data of a sample of 58 main-sequence, mainly Vega-type, and pre-main sequence stars. The data were taken during four observing runs in the period May 1998 to January 1999 and form part of a coordinated effort with simultaneous optical spectroscopy and photo-polarimetry. The near-IR colors of the MS stars correspond in most cases to photospheric colors, although noticeable reddening is present towards a few objects, and these stars show no brightness variability within the observational errors. On the other hand, the PMS stars show near-IR excesses and variability consistent with previous data.

The evolution of young stars and disks is driven by the interplay of several processes, notably the accretion and ejection of material. These processes, critical to correctly describe the conditions of planet formation, are best probed spectroscopically. Between 2020 and 2022, about 500orbits of the Hubble Space Telescope (HST) are being devoted in to the ULLYSES public survey of about 70 low-mass (M⋆ ≤ 2 M⊙) young (age < 10 Myr) stars at UV wavelengths. Here, we present the PENELLOPE Large Program carried out with the ESO Very Large Telescope (VLT) with the aim of acquiring, contemporaneously to the HST, optical ESPRESSO/UVES high-resolution spectra for the purpose of investigating the kinematics of the emitting gas, along with UV-to-NIR X-shooter medium-resolution flux-calibrated spectra to provide the fundamental parameters that HST data alone cannot provide, such as extinction and stellar properties. The data obtained by PENELLOPE have no proprietary time and the fully reduced spectra are being made available to the whole community. Here, we describe the data and the first scientific analysis of the accretion properties for the sample of 13 targets located in the Orion OB1 association and in the σ-Orionis cluster, observed in November–December 2020. We find that the accretion rates are in line with those observed previously in similarly young star-forming regions, with a variability on a timescale of days (≲3). The comparison of the fits to the continuum excess emission obtained with a slab model on the X-shooter spectra and the HST/STIS spectra shows a shortcoming in the X-shooter estimates of ≲10%, which is well within the assumed uncertainty. Its origin can be either due to an erroneous UV extinction curve or to the simplicity of the modeling and, thus, this question will form the basis of the investigation undertaken over the course of the PENELLOPE program. The combined ULLYSES and PENELLOPE data will be key in attaining a better understanding of the accretion and ejection mechanisms in young stars.

We have compared the B−V colour excess, E(B-V), obtained for a sample of five optically visible massive YSOs both from diffuse interstellar bands (DIBs) in their spectra and from their optical continuum slopes. Our targets are HD 200775, BD+40 o 4124, MWC 1080, MWC 297 and MWC 349A. First, E(B-V) towards each of the targets is derived by dereddening the observed continua to match those of B-type standard stars. A survey of DIBs in the spectra of the massive YSOs, and a control field star, then reveals that the DIBs are significantly weaker in the former than would be expected based on the total E(B-V) values. This result is strengthened by the finding that the DIBs in the control field star, HD 154445, have on average the strength expected from its continuum E(B-V).A rough estimate of the foreground reddening of intervening diffuse interstellar medium shows it to be smaller than the DIB-E(B-V), implying that at least part of the DIB carriers are formed within the parental molecular clouds in which the YSOs are embedded. The formation efficiency of the DIBs varies strongly however from cloud to cloud. The DIB-E(B-V) compares favourably with the total E(B-V) towards BD+40 o 4124, but is almost negligible in the line of sight towards MWC 297. Despite this general, but not unexpected, deficit we provide evidence that the DIB at 5849Å is a good tracer of total extinction in these lines of sight.