The polar vortex, a river of air that circles Antarctica in the austral winter, is essential.

It was their third attempt over three seasons, all in 2012, including an austral winter attempt in August.

And more than this again; the temperature had fallen sensibly: this was probably a forewarning of the austral winter.

The president introduced an austerity programme, named after the new currency - the austral - with which he replaced the peso.

These singular objects form as striking a peculiarity of the austral heavens as does the great ''Coal-sack'' described in Chapter 1.