We are stardust, we are golden

We are billion year old carbon

- 'Woodstock', Joni Mitchell

Joni Mitchell was right. Physicist Edward Zganjar says 'we are made of stardust' adding:

The iron in our blood and the calcium in our bones were all forged in stars.

Understanding the universe and our place within it has long been a primary focus of enquiry for us humans; perhaps Edward Zganjar's work has helped bring outer space down to Earth. If you're wearing gold jewellery, the chances are it was originally produced in a supernova explosion towards the end of the star's life.

The question of whether we are alone among the stars has seemed impossible to answer. However, during the first few months of 2007, 40 exoplanets (plants orbiting other stars) were discovered. There are now 244 known exoplanets; the first of these was only discovered in 1995. At the rate these planets are being discovered, perhaps proof of life might be found sooner rather than later.

• Does the news we are all from outer space change the way you see your position in the universe?

• Should we start to think of ourselves as aliens if we were all originally created from stardust?

• Do you think there aliens already walking among us?

• Could life be conceivably possible on Venus or another apparently inhospitable planet for a life form which we could barely imagine?

• So far, there have not been any planets which have been found which have conditions suitable for 'life' to flourish. Do you think a more accurate phrase would be 'life as we know it'?

• If the universe is infinite, could that mean there is an infinite variety of life forms out there – only a tiny amount of which might be detectable by our instruments?

• Or could we really be alone; after all, the conditions for life on earth depend on such seemingly astonishingly lucky circumstances. If the earth was a wee bit nearer/further away from the sun we'd be toast. Or ice cubes.

• If we made contact with 'aliens' - say they landed in a field in a big ship - how do you think we'd react? With garlands, and peace signs? Or might we be a bit more suspicious and fearful, point guns at them, etc?

A final thought...

Q: What do you call an alien with no eyes?
A: Alen.