INFRARED AND MILLIMETER OBSERVATIONS OF THE GALACTIC SUPERLUMINAL SOURCE GRS-1915+105

Millimeter observations of the galactic source of relativistic ejectio ns GRS 1915+105 (Mirabel & Rodriguez 1994) are consistent with this so urce being at a kinematic distance D = 12.5 +/- 1.5 kpc from the Sun, behind the core of a molecular cloud at 9.4 +/- 0.2 kpc. At this dista nce, GRS 1915+105, frequently radiating similar to 3 x 10(38) erg s(-1 ) in the X-rays, becomes the most luminous X-ray source in the Galaxy. The total hydrogen column density N(H) = 4.7 +/- 0.2 x 10(22) cm(-2) along the line of sight corresponds to a visual absorption A(v) = 26.5 +/- 1 magnitudes. The infrared counterpart of GRS 1915+105 exhibits i n the 1.2 mu m - 2.2 mu m band variations of similar to 1 magnitude in a few hours and of similar to 2 magnitudes over longer intervals of t ime. In the infrared, GRS 1915+105 is strikingly similar to SS 433, an d unlike any other known stellar source in the Galaxy. The infrared re semblance in absolute magnitude, color, and time variability, between these two sources of relativistic ejections suggests that GRS 1915+105 , as SS 433, consists of a collapsed object (neutron star or black hol e) with a thick accretion disk in a high-mass-luminous binary system.