A new technique has been used to estimate the age of globular star cluster M92 at 13.8 billion years, plus or minus 0.75 billion years. This is an almost exact match for the estimated age of the Universe, albeit with wider error bars. Either this nearby collection of stars formed as soon as possible after the Big Bang, or we’ve been underestimating how old the Universe really is.
Globular clusters are, as the name suggests, near-spherical collections of tens of thousands of tightly packed stars sitting outside galaxies. In general, they are very old – but some are considerably older than others, and these attract the most interest from astronomers as they provide us with insight into the universe’s earliest days.
M92 is a favorite object for northern hemisphere amateur astronomers, being easily visible in binoculars, but to professionals it’s particularly significant as a candidate for the oldest globular cluster in our near vicinity. Indeed, as a forthcoming paper notes, M92 is often used as a benchmark against which we measure newly forming galaxies seen soon after the Big Bang.
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