Intermediate – Page 70 – British Astronomical Association

The Radio Astronomy Group in 2018

The deep-sky delights of Hydra

Hydra, the water snake is – rather appropriately – a sprawling constellation of the spring sky, covering almost six hours

Record fade of variable star SV Sge

RCB stars are extremely rare, hydrogen deficient, carbon rich giant stars whose luminosity varies in two ways – small amplitude

Letters

Noctilucent cloud over Britain & Western Europe, 2017

A summary by the Assistant Director of the Aurora & NLC Section of noctilucent cloud (NLC) activity during the 2017 season.

Jupiter’s North Equatorial Belt & Jet: II. Acceleration of the jet & the NEB fade in 2011–’12

Paper I described the normal features of the North Equatorial Belt (NEB) in recent years. This paper describes an exceptional set of apparently coordinated changes which occurred in 2011–’12, after more localised precursors in 2008 & 2010. The large dark formations on the NEB southern edge (NEBs) progressively disappeared until none remained. In the sectors of NEBs thus vacated, smaller dark features all moved with unprecedented ‘super-fast’ speeds, which were modulated by the few normal features while they lasted before accelerating further. These changes have several profound implications for understanding the dynamics of the region.

The myth of Henry Hudson’s sunspots

This paper examines claims that the explorer Henry Hudson saw sunspots with the naked eye during sea voyages in both 1590 & 1609. It is argued that there is no evidence to link Hudson with the 1590 observations, and that the presumed sunspot of 1609 – accepted by some leading experts in the history of solar activity – is based on a false premise.

The eastern & western elongations of Venus, 2007–’17. Part I. The sunlit hemisphere

Fourteen successive morning and evening elongations of Venus from 2007–’17 are reviewed. The work of 153 observers covered the time period of ESA’s Venus Express and Japan’s Akatsuki missions, and wavelengths from 335–1750nm. Part II will discuss phenomena of the nocturnal hemisphere: the infrared thermal emission from the planet’s surface, and the Ashen Light.

FROM THE JOURNAL ARCHIVE

Auroral & NLC activity, 2018 Dec 1 – 2019 Feb 28

Most of the aurora sightings in this report are from Scotland, with the majority caused by coronal holes. There was