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Oldest Known Star In the Universe Discovered
Zothecula writes "A team of astronomers at The Australian National University working on a five-year project to produce the first comprehensive digital survey of the southern sky has discovered the oldest known star in the Universe. The star dates back 13.7 billion years, only shortly after the Big Bang itself. It's also nearby (at least, from a cosmological perspective) — about 6,000 light-years away. The star is notable for the very small amount of iron it contains (abstract). The lead researcher, Stefan Keller, said, 'To make a star like our Sun, you take the basic ingredients of hydrogen and helium from the Big Bang and add an enormous amount of iron – the equivalent of about 1,000 times the Earth's mass. To make this ancient star, you need no more than an Australia-sized asteroid of iron and lots of carbon. It's a very different recipe that tells us a lot about the nature of the first stars and how they died.'"
According to TFA this star itself was likely born from the death of a genuinely primordial star (which would have started with almost nothing by hydrogen and helium). One of the upshots of this work is that some primordial stars may have produced much less iron than some models have suggested which could explain some discrepancies in the observed isotopic ratios in some old stars. According to the actual article (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12990.html which may be behind a paywall) this star has an apparent visual magnitude of 14.7. This puts this star just in the limits of amateur observations. Charon has an apparent magnitude of around 15.5 http://en.wikipedia.org/wiki/Charon_(moon) and that's been successfully imaged by amateurs (larger apparent magnitude means dimmer because astronomers are silly) http://www.universetoday.com/20351/charon-imaged-by-amateur-astronomers/ , so this star could be looked at by a dedicated amateur in the southern hemisphere.
No, they mean the lead that rhymes with read, not the one that rhymes with read.
Very small stars are like small cars, very fuel efficient. Large stars have a higher pressure in the core, and fusion runs faster. The core is so dense it does not convect. The amount of fuel in the core is all the star has to fuse. A red dwarf is fully convective. All the gas in the star drops down into the core, heats up, and raises back to the surface. The star can therefore fuse all the gas in the entire star, not just the gas in the core. So, it uses all its potential fuel, very conservatively. Therefore, it can last a long time.