Over the last two decades, several thousand exoplanets have been identified, and their
study has become a high scientific priority. Direct imaging of nearby exoplanets and the …

In this review/tutorial we explore planetary nebulae as a stage in the evolution of low-to-
intermediate-mass stars, as major contributors to the mass and chemical enrichment of the …

Observations of circumstellar environments that look for the direct signal of exoplanets and
the scattered light from disks have significant instrumental implications. In the past 15 years …

Context. Accreting planetary-mass objects have been detected at H α, but targeted searches
have mainly resulted in non-detections. Accretion tracers in the planetary-mass regime …

Context. The SPHERE “planet finder” is an extreme adaptive optics (AO) instrument for high
resolution and high contrast observations at the Very Large Telescope (VLT). We describe …

Context. In recent years, our understanding of giant planet formation progressed
substantially. There have even been detections of a few young protoplanet candidates still …

Context.(Pre-) Transitional disks show gaps and cavities that can be related to ongoing
planet formation. According to theory, young embedded planets can accrete material from …

Aims. NGC 6240 is a well-studied nearby galaxy system in the process of merging. Based
on optical, X-ray, and radio observations, it is thought to harbor two active nuclei. We carried …

Context. The mechanisms of planet formation are still under debate. We know little about
how planets form, even if more than 4000 exoplanets have been detected to date. Recent …

Context. Jets are rarely associated with pre-main sequence intermediate-mass stars. This
contrasts with the frequent detection of jets in lower mass or younger stars. Optical and near …