http://www.spacedaily.com/reports/Myste ... s_999.html
And in a bit of overt ad-hoc speculation:Imagine having three clocks in your house, each chiming at a different time. Astronomers have found the equivalent of three out-of-sync "clocks" in the ancient open star cluster NGC 6791. The dilemma may fundamentally challenge the way astronomers estimate cluster ages, researchers said.
Using NASA's Hubble Space Telescope to study the dimmest stars in the cluster, astronomers uncovered three different age groups. Two of the populations are burned-out stars called white dwarfs. One group of these low-wattage stellar remnants appears to be 6 billion years old, another appears to be 4 billion years old. The ages are out of sync with those of the cluster's normal stars, which are 8 billion years old.
"The age discrepancy is a problem because stars in an open cluster should be the same age. They form at the same time within a large cloud of interstellar dust and gas. So we were really puzzled about what was going on," explained astronomer Luigi Bedin, who works at the Space Telescope Science Institute in Baltimore, Md.
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"This finding means that there is something about white dwarf evolution that we don't understand."
Phew, for a minute there, I thought they were going to have to "invent" a solution! Ohh wait...After extensive analysis, members of the research team realized how the two groups of white dwarfs can look different and yet have the same age. It is possible that the younger- looking group consists of the same type of stars, but the stars are paired off in binary-star systems, where two stars orbit each other. Because of the cluster's great distance, astronomers see the paired stars as a brighter single star.
"It is their brightness that makes them look younger," said team member Maurizio Salaris of Liverpool John Moores University in the United Kingdom.
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"Our demonstration that binaries are the cause of the anomaly is an elegant resolution of a seemingly inexplicable enigma," said team member Giampaolo Piotto the University of Padova in Italy.
Bedin and his colleagues are relieved that they now have only two ages to reconcile: an 8- billion-year age of the normal stellar population and a 6-billion-year age for the white dwarfs. All that is needed is a process that slows down white-dwarf evolution, the researchers said.
Have they actually measured any binaries? Or is it strictly an ad-hoc assertion without ACTUAL observations to back it up?
Cheers,
~Michael Gmirkin