2003IAUC.8253....1M

M. Mikolajewski and T. Tomov, Uniwersytet Mikolaja Kopernika; R. Kurtev, Sofia University; L. Georgiev, Universidad Nacional Autonoma de Mexico; and A. Wolszczan, Pennsylvania State University, write that they obtained UBVI and H_alpha images of V838 Mon and its light echo with the 1.5-m telescope at San Pedro Martir on Oct. 18.5 UT, noting that V838 Mon recently has become bluer (cf. IAUC 8202, 8210) and comparable in bands U and B to its previously reported B3-V companion (IAUC 8005). V838 Mon itself, and an additional star about 1" to the southeast, are clearly visible in their U images. The B-band centroid of the V838 Mon image is shifted in the same direction, while frames at longer wavelengths display only one star at this position. The authors' low-resolution spectral observations of V838 Mon obtained on Jan. 27.2 and Mar. 24.1 with the 10-m Hobby-Eberly Telescope (range 430-730 nm, resolving power 650) also show a composite spectrum. The blue and yellow regions are dominated by a reddened (V about 15.9; B about 16.5), normal B3-V star. The red part of the spectrum is characterized by strong features belonging to an extremely cool (L-type?) supergiant, evidently a remnant of the V838 Mon outburst. The analyses of the interstellar features and reddening suggest that the B3-V star is a blending objects lying about 1000 pc behind V838 Mon. Two rings are apparent in the current light echo visible on the new V, I, and H_alpha images: an almost concentric outer circle with radius about 50" and an eccentric inner ellipse with half-axes of about 25" x 32".