The Hubble Space Telescope Extragalactic Distance Scale Key Project. IX. The Discovery of Cepheids in NGC 2090

We report on the discovery of 34 Cepheid variables in NGC 2090, with periods ranging between 5 and 58 days. Apparent V and I period-luminosity relations for Cepheids with P >= 10 days have been constructed, assuming a fiducial distance modulus, μ₀, of 18.50 +/- 0.10 mag and a reddening, E(B-V), of 0.10 mag for the Large Magellanic Cloud. Using the ALLFRAME photometry package, an inferred reddening of E(V-I) = 0.09 +/- 0.02 mag (internal error) and a true distance modulus of 30.45 +/- 0.16 (random) +/- 0.16 (systematic) mag for NGC 2090 are found. The corresponding distance is 12.3 +/- 0.9 (random) +/- 0.9 (systematic) Mpc, a value that agrees at the 2.5% level with that derived from an independent analysis using a modified version of the DoPHOT photometry package.

Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, operated by AURA, Inc., under NASA contract No. NAS5-26555.