Arid Lands

The NYT has an article and video clip promo for photographer Murray Fredericks' trekking about on Australia's Lake Eyre:

The Lake Eyre basin stretches across 750,000 square miles of inland Australia, draining nearly a quarter of the continent’s land mass. During the rare rainy season, Lake Eyre fills with water; the rest of the time, its lake bed forms a vast salt flat the size of Holland.

Fredricks has an online gallery here; the photos are quite lovely.
And continuing to promote astronomy with excellent geology, APOD today shows hills eroded from layered deposits on Mars