OBSERVATIONS OF NOVA CYGNI 1992 WITH A LONG-BASE-LINE OPTICAL INTERFEROMETER

Nova Cygni 1992 was observed with the MkIII optical interferometer on several nights in 1992 February; usable data were obtained on February 28 and 29. This marks the first time that a nova has been resolved ap proximately 10 days after maximum light. A uniform disk model fitted t o the data in three wide-band (approximately 25 nm) filters gives a di ameter of 3.8 mas. The uniform disk diameter in a 10-nm bandpass cente red on the Halpha line was 5.1 mas. From this number, and adopting an expansion velocity of approximately 1100 km s-1, the distance to the n ova is estimated to be approximately 2.5 kpc.