WITH interplanetary spaceflight still the realm of science fiction, Sydneysiders can walk around the sun and its planets when a temporary exhibition of our solar system is erected along the city's beaches this weekend.

The scale-model of the solar system will begin at Maroubra Beach with the sun and the first five planets, including Earth, along the promenade, and end with the dwarf planet, Pluto, at Trenerry Reserve in South Coogee almost three kilometres away.

The sizes of the planets and sun, and the distance between them, have been accurately represented on a scale of one to 2 billion.

The Solar System by the Sea was the brainchild of artist and scientist Christopher Lansell, who constructed a similar exhibition along Melbourne's foreshore in 2005. The models were so popular the council installed them as a permanent display.

''Everyone that sees the model, the distance Earth is from everything else, finds it a really puzzling experience,'' Mr Lansell said.

The display is open from 9am to 4.30pm Saturday and Sunday as part of National Science Week, with Dr Karl Kruszelnicki hosting a planetary walk at 11am on Sunday.

Source: smh.com.au

By Nicky Phillips