CometBase Alert №3. Comet 17P/Holmes - outburst!

Comet 17P/Holmes, famous for its largest known cometary outburst on October 23, 2007, appears to be in outburst again. This was first reported by R. Miles, who observed the comet using a 2.0-m telescope (Faulks Telescope North, Hawaii) on January 28.25, 2015. Comet looked condensed in the images having a compact coma of diameter 10''-12''. Comet magnitude determined with a 30'' aperture: 14.3R, 14.6V.

According to R. Miles, before the outburst, during January 22-26 comet seemed to be in a quiescent state with faint coma and a distinct central condensation, magnitude determined with a 30'' aperture was 18.0R. Thus, the total amplitude of the outburst is about 4 magnitudes. According to calculations of R. Miles outburst started on 26.7 ± 0.4 of January.

Expanding coma after an outburst reveals a considerable degree of asymmetry.

Observations of Comet 17P/Holmes are very important now for tracing back the occurred outburst progress.