BAA E-Circular 00109

2003 July 1

Dust storm alert

Apart from a small dust cloud seen NW of Solis Lacus for a few days in late May, the planet has shown no signs of telescopic dust storm activity – until today! Visual and CCD observations for July 1 reveal considerable albedo changes since the previous day in the areas of Iapigia, Hellas and environs. Several small discrete dust clouds have been observed. Dr D.C. Parker reports as follows in an e-mail dated July 1:

‘Significant changes have occurred over the past 24 hours: 1. Mare Tyrrhenum, Syrtis Minor, and Crocea–Oenotria have lightened considerably, appearing to be covered by a thin whitish cloud... These features were dark and ‘normal’ on June 30... and throughout June. 2. Bright ochre spots [were] rimming Hellas and obscuring Deltoton–Iapygia... Little detail noted on the floor of Hellas.’

The region is already being lost over the morning terminator when viewed at dawn from the UK, but observers suitably placed are requested to observe frequently and to report their results to the undersigned. It is not yet possible to assess whether this event will be large or small!

Richard McKim, Director

2003 July 1