The Sun's 'twin' that could reveal our fate 4 billion years in the future We have now obtained superb-quality spectra from the VLT and can scrutinise solar twins with extreme precision, to answer the question of whether the Sun is special. Our own sun is around 4.6 billion years old, while HIP 102152 is 8.2 billion years old. Located in the constellation of Capricornus, the astronomers analysed the spectrum of light that came from the star. The Very Large Telescope (VLT) at ESO's Cerro Paranal observing site (European Southern Observatory) The spectrum produced by a star acts like an identifying bar code, providing details about its chemical composition and history. In the big bang large amounts of hydrogen and helium were produced along with light elements such as lithium. As stars age, this lithium is burned up or destroyed, providing scientists with an ability to tell how old a star is. Our Sun has just one per cent of the lithium that it would have had when it was formed. The new observations of HIP 102152 have already allowed astronomers to pin down the correlation between a sun-like stars age and its lithium content. Tala Wanda Monroe, also from the Universidade de São Paulo and another of the researchers, said: "We have found that HIP 102152 has very low levels of lithium. This demonstrates clearly for the first time that older solar twins do indeed have less lithium than our own Sun or younger solar twins. We can now be certain that stars somehow destroy their lithium as they age, and that the Sun's lithium content appears to be normal for its age. The researchers, whose findings are published in the journal Astrophysical Journal Letters, also found an unusual chemical signal that has not yet been found in other solar twins, but has in the sun. Both HIP 102152 and our Sun contain low levels of elements that are locked up in meteorites and here on Earth. It suggests that HIP 102152 may also have rocky planets. If this turns out to be the case, it could well reveal what awaits our own solar system in four billion years.