Wednesday, June 3

ALMA and Dinosaur Eggs

The other day, the Bing homepage used the image above of the Atacama Large Millimeter/submillimeter Array (ALMA), the $1.4 billion radio telescope in the Chilean desert. So I went to the ALMA homepage to read the lastest news and saw a story from last month detailing the discovery of a globular cluster with no stars within intersecting galaxies. Here is some of the story: 
"We may be witnessing one of the most ancient and extreme modes of star formation in the universe," said Kelsey Johnson, an astronomer at the University of Virginia in Charlottesville and lead author on a paper accepted for publication in the Astrophysical Journal. "This remarkable object looks like it was plucked straight out of the very early universe. To discover something that has all the characteristics of a globular cluster, yet has not begun making stars, is like finding a dinosaur egg that's about to hatch."
This object, which the astronomers playfully refer to as the "Firecracker," is located approximately 50 million light-years away from Earth nestled inside a famous pair of interacting galaxies (NGC 4038 and NGC 4039), which are collectively known as the Antennae galaxies. The tidal forces generated by their ongoing merger are triggering star formation on a colossal scale, much of it occurring inside dense clusters.
The image captured by ALMA is below. The radio telescope was set up to better understand issues such as planetary formation, so this is a good place to start.