We have spent a lot of time and effort attempting to make direct, unambiguous contact with life on other worlds - sending up snippets of Beatles songs or brief Morse code messages. What we should be doing is sending up tubs of human excrement and lemons attached to electrodes.
Art is supposed to be the story of what it is to be human. So what would aliens make of contemporary art, an aspect of life that even humans find hard to digest? This is the amusing idea behind the Martian Museum of Terrestrial Art, at the Barbican Art Gallery in London (until May 18). The show bundles together about 175 rather disparate pieces (including Scott King's Pink Cher, above) from the Sixties to the present day, all presented as artefacts of human rituals and behaviour, as interpreted by extra-terrestrials.
What function does this kind of art have, ask the aliens, as perhaps only an alien would of a piece such as Sigmar Polke's "Apparatus Whereby One Potato Can Orbit Another" (a potato on a wire suspended under a stool)?
A highlight is the 1979 piece "Cultural Ties" by American artist Jeffrey Vallance, who sent neckties to heads of state around the world, asked for one in return and framed the replies. Many comply, some return the tie, Austria doubts the value of the exercise but sends a tie anyway. Humans, eh?