Dying Star System Observed Surrounded by Ring of Dust

Usually a phenomenon only seen with young stars


Stars like the sun eventually run out of hydrogen fuel and puff-up into red giants at the end of their lives — a precursor to a suicidal shedding of gas, decimating any nearby planets, eventually leaving a tiny white dwarf remnant. But a nearby star, located around 100 light-years away, has been spotted in the brief stage before the red giant phase of its death throes — and it has a dusty disk usually exclusive to young stars.

Kappa Coronae Borealis (? CrB) is a little more massive than our sun, weighing-in at 1.5 solar masses. It has been steadily burning through its supply of hydrogen for 2.5 billion years, but now it has entered its "retirement years" as a subgiant. ? CrB is known to have one massive planet (around two Jupiter masses) in orbit with evidence of a second world. But most interesting is the presence of a dusty ring of debris surrounding the star, and the European Herschel space observatory is the first telescope to see such a ring surrounding such an old star.