We study the morphologies of core collapse supernova remnants (CCSNRs) and find that about third of CCSNRs have two opposite `ears' protruding from their main shell, and that the typical energy that is required to inflate these ears is about 10 percents of the explosion kinetic energy. We argue that these properties are most compatible with the expectation from the explosion jet feedback mechanism (JFM).
RW Aur is a young binary system showing strong signatures of a recent tidal encounter between the circumprimary disk and the secondary star. The primary star has recently undergone two major dimming events (Δmag ≈ 2 in V-band), whose origin is still under debate. To shed light on the mechanism leading to the dimming events, we study the extinction properties, accretion variability, and gas kinematics using absorption lines from the material obscuring star RW Aur A.
The nucleus of a so-called "active" galaxy contains a massive black hole that is vigorously accreting material. As a result, the nucleus often ejects bipolar jets of rapidly moving charged particles that radiate brightly at many wavelengths, in particular radio wavelengths. Active galaxies display a range of dramatically different properties, and the ones that are bright in the radio can beam as much as one trillion solar luminosities of radiation into space at those wavelengths.