Astronomers studying a star nearly identical to our Sun — a 'solar twin' — have made some important discoveries, clearing up a mystery about the age and composition of the Sun, and possibly showing that this star has a planet system similar to our own. Anyone looking for answers about our Sun can get a lot of help from 'solar twins'. By examining these stars, they can get an idea of whether the Sun is remarkable in some way, or if it's fairly typical. They can also see what our Sun was probably like in the past, and what it will possibly be like in the future. One question that's been on astronomer's minds for awhile is whether or not there's a connection between a star's age and the amount of lithium they detect in it. Lithium is a fairly simply element, which was created along with hydrogen and helium during The Big Bang, and it would have been abundant in the materials that formed the Sun. However, now, the Sun has only a very small amount of lithium in it, roughly 1% the original amount. Higher amounts have been seen in younger stars, like 18 Scorpii, another solar twin in the study, but no specific connection to age could be made until now. Read More at Yahoo! News.