RA 07h 25m 51.28s DEC -07 44’ 08.09”
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Astronomers at the INAF-Osservatorio
Astronomico di Padova in Italy are studying the unique symbiotic binary V694
Monoceros which is now on a steep rise in brightness. Indications are that it
is about to surpass the record level attained during the last, and much
studied, outburst of 1990, which was the brightest event in the historical
light-curve of the object. At that time V694 attracted special interest by
showing deep and broad absorptions, blue-shifted by 6000 km/s and completely
detached from corresponding emission lines, as if originating in discrete
blobs, ejected from the central star and rapidly accelerated to large
velocities.
These absorptions have shown
considerable variability in intensity, profile and velocity over the years. These latest
measurements for February 5.967 UT shows V694 at Mag 8.88. For comparison,
the peak brightness in 1990 was reached at Mag 9.2.
On February 5 the astronomers
collected spectra on V694, in low resolution with the Asiago 1.22m telescope
and in high resolution Echelle mode with the Multi Mode Spectrograph on the
Varese 0.61m telescope. On top of an A-type hot continuum (with Balmer
continuum in absorption), two types of absorption and two types of emission
lines were observed. The absorptions in NaI D1-D2, CaII H-K, HeI 5876, and FeII
multiplet 42 are located at -1900 km/s, 200-300 km/s wide, with a round profile
and are completely detached from the corresponding emission lines.
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