NGC 3370 (also known as UGC 5887 or Silverado Galaxy) is a spiral galaxy about 98 million light-years away in the constellationLeo. It is comparable to our own Milky Way both in diameter (100,000 light years) and mass (10¹¹ solar masses). NGC 3370 exhibits an intricate spiral arm structure surrounding a poorly defined nucleus. NGC 3370 was likely discovered by William Herschel, who provided it with the designation II 81. His son John later designated it 750. William Herschel cataloged I 80 to NGC 3348 before and II 82 to NGC 3455 after NGC 3370.