UW Centauri is making a comeback

by Dave Blane

Still very much in its active state but significantly brighter than it has been for a long time, UW Centauri has recovered to 14th magnitude (max is magnitude 9) in the current minimum which appears to have begun sometime between September 2008 and the beginning of 2009.

The AAVSO LCG nicely illustrates the current long, deep fade to as faint as 17.8V (a record low) in April 2013 . It also suggests that the current 5 year-long minimum is, up to now, the second longest one on record for this RCB, going back more than 60 years. But UW Cen is no stranger to failed comebacks. The long term light curve shows the star is more likely than not to fade out again, perhaps several times, before eventually making it back to full maximum. This phenomenon has already occurred once during the present fade episode – the star recovered to at least 14.7V in August 2012 before dropping off to the 17th magnitude in the first quarter of 2013.

The star is now within reach of 200mm and larger telescopes and it is well worth watching to see if it recovers to its normal brightness of 9th magnitude. A finder charts for UW Centauri can be downloaded from the AAVSO website.

An interesting paper on this  star may be found by following the link :

The ever-changing circumstellar nebula around UW Centauri

UW Centauri