A team of scientists led by RIT’sSukanyaChakrabarti has made an important astronomical discovery. Chakrabarti, who is with the university’s School of Physics and Astronomy, analyzed data to find four young stars approximately 300,000 light years away. These young stars are Cepheid variables that astronomers use to measure distances.
This cluster of young, pulsating stars discovered at the far side of the Milky Way may mark the location of a previously unseen dark-matter dominated dwarf galaxy hidden behind clouds of dust.
The stars appear to be associated with a dwarf galaxy Chakrabarti predicted in 2009 based on her analysis of ripples in the Milky Way’s outer disk
Invisible particles known as dark matter make up 23 percent of the mass of the universe. The mysterious matter represents a fundamental problem in astronomy because it is not understood, Chakrabarti said.
“The discovery of the Cepheid variables shows that our method of finding the location of dark-matter dominated dwarf galaxies works,” she said. “It may help us ultimately understand what dark matter is made up of. It also shows that Newton’s theory of gravity can be used out to the farthest reaches of a galaxy, and that there is no need to modify our theory of gravity.”
The team that Chakrabarti was part of analyzed data collected by the European Southern Observatory’s VISTA telescope. Chakrabarti analyzed VISTA’s database of tens of millions of stars to find these clustered Cepheid variables in the Norma constellation, all within one degree of each other.
