`Unveiling the Mysteries of the Leo Ring'

Monday November 7 Brown Hall 261 4 PM

Speaker: Dr. Mark Giroux (East Tennessee State University)

Title: `Unveiling the Mysteries of the Leo Ring'

Over twenty-five years ago a gigantic ring of neutral hydrogen gas was found in the region of the constellation Leo.   The ring has a diameter of over six hundred thousand light years and has a mass two billion times that of the Sun.   At the time this ring was the subject of speculation about its origins-is it the remnant of a tidal interaction between nearby galaxies, or is it primordial gas left over from the formation of these galaxies?   Despite the passage of twenty-five years and numerous additional observations, the Leo Ring's origins remain unknown.   We have obtained Hubble Telescope data which we hope to use to resolve this mystery, and I will report on the present state of our knowledge.

Refreshments will be served at 3:45 PM