Science News - 04 May 2010
A preliminary analysis of elderly stars in the Milky Way appears to strike a blow against the prevailing theory of galaxy formation. The study suggests that several large and seemingly disparate chunks of the Milky Way galaxy formed at the same time from the collapse of a single blob of gas and dust.
That’s in direct contrast to the leading galaxy-formation scenario, which holds that the Milky Way and other galaxies began small and grew bit by bit for the most part, gravitationally acquiring intergalactic gas and dust and merging with galaxies in their immediate neighborhood.
New infrared images of the Milky Way globular cluster 47 Tucanae (this one recorded at a
wavelength of 1.6 micrometers), reveal that both the cluster and the Milky Way's central
bulge are 11 billion to 12 billion years old and may have formed simultaneously with the
Milky Way’s halo. (H. Richer, NASA, ESA)