Building a family tree of stars

Feb. 20 (UPI) -- Using chemical signatures as a stand-in for DNA, researchers constructed an evolutionary tree of stars. Researchers have begun translating ideas from evolutionary biology for use in a new scientific discipline called galactic archaeology.

"The use of algorithms to identify families of stars is a science that is constantly under development," aula Jofré, a researcher at the University of Cambridge's Institute of Astronomy, explained in a news release. "Phylogenetic trees add an extra dimension to our endeavours which is why this approach is so special. The branches of the tree serve to inform us about the stars' shared history."

To build their stellar family tree, researchers collected chemical composition data for 22 stars, including the sun. They also compiled the age and kinetic characteristics of each star -- observations collected from a variety of space observatories.

The chemical signatures of stars can reveal their relatedness. Stars with similar chemical composition were likely born from the same molecular gas cloud. Stellar ages help astronomers organize these relationships chronologically.

The oldest of the 22 stars in the new family tree is at least 10 billion years old. The youngest is 700 million years old.

Researchers used analysis techniques for the study of animal evolution to plot the changing chemical composition of stars included in the family tree.

"The differences between stars and animals is immense, but they share the property of changing over time, and so both can be analyzed by building trees of their history," said Robert Foley, a professor of human evolution at Cambridge.

Researchers published their family tree in the Monthly Notices of the Royal Astronomical Society.