Complicating the search is the fact that for every star undergoing microlensing, there are thousands of stars changing in brightness for other reasons ( about 2 % of the stars in a typical source field are naturally variable stars ) and other transient events ( such as novae and supernovae ), and these must be weeded out to find true microlensing events.
32.
Control IAS DC000093 ) . jpg should be filled with the sculptor's name, " and photographer : unknown " and the | source field with " Goode, James M ., " Washington Sculpture : A Cultural History of Outdoor Sculpture in the Nation's Capitol, " Baltimore, MD : Johns Hopkins University Press, 2008, no . 3.30 " as the SIRIS catalog page is saying.
