  M85OT2006-1 is the latest and most brilliant addition to the small group of
known Luminous Red Novae (LRNe). An identifying characteristic of the
previously detected events (M31 RV, V4322 Sgr & V838 Mon) was a spectral
red-ward evolution connected with an emerging infrared component following the
optical decay. Here we report on the discovery of a similar feature in
Keck/NIRC and Spitzer photometry of M85OT2006-1 six months post-eruption. We
find that its 2.1-22 micrometer spectral energy distribution is best described
by a black body with effective temperature T_eff=950+-150 K and bolometric
luminosity L=2.9+-0.5x10^5 L_sun. Assuming spherical geometry, the black body
effective radius, R=2.0+-0.5x10^4 R_sun, and corresponding expansion velocity,
v=870+-260 km/s, are remarkably similar to the properties of M31 RV 70 days
after its eruption. Furthermore, we propose a search strategy for LRNe in the
local Universe making use of the longevity of their infrared excess emission
and discuss the expected number of events in the Spitzer Infrared Nearby
Galaxies Survey.
