Margaret Turnbull- is an American astronomer. She received her PhD in Astronomy from the University of Arizona in 2004. Turnbull is an authority on “Habstars,” solar twins and planetary habitability. In 2002, Turnbull developed the HabCat along with Jill Tarter, a catalog of potentially habitable stellar systems. The following year Turnbull went on to further identify 30 particularly suitable stars from the 5,000 in the HabCat list that are within 100 light years of Earth. In 2007, Turnbull was named a “Genius” by CNN for her work cataloging stars most likely to develop planets that could support life and intelligent civilizations.