NGC 3644 (also IC 684, UGC 6373, MCG 1-29-37 and PGC 34814) is a magnitude +14.2 spiral galaxy located 672 million light-years away in the constellation Leo.
The galaxy was discovered by German astronomer Albert Marth using a 121.92 cm (48 inch) reflector at William Lassell's Tigné Point observatory in Sliema, Malta, on the 22nd March 1865. The galaxy was rediscovered by Guillaume Bigourdan in April 1888 and relisted as IC 684.
Right Ascension 11h 21m 32.9s, Declination +02° 48' 37"
