Paul Murdin

Nighttime skies above the Canary Islands

Abstract The Canary Island observatories are two of the most studied astronomical sites in the world. Half the nights are photometric, most time is usable. Seeing is excellent and there are tentative indications that it is to some extent predictable. Atmospheric transmission is usually good, and well-behaved when it is not. Water vapour is low and well-behaved. Night-sky brightness is low. The paper summarises quantitative data on the above topics.

The supernova in the large magellanic cloud

Abstract The appearance in February 1987 of a naked-eye supernova in a nearby galaxy to our own was the first supernova of this brightness for 383 years. Neutrinos detected from the supernova marked the start of the subject of neutrino astronomy. The light from the star was a uniquely bright probe to the regions of interstellar space, in our Galaxy and another, and to the intergalactic space between them.

Optical continuum from SS 433 — star or accretion disk?

Abstract The continuum (0.2–2μ) from SS 433 appears to be black-body in form. A luminous reddened star fits the data. Constraints on accretion disk spectra are discussed.