------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 2659 2010 Jly 16 16.10UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074 INTERNET: GUY@TAHQ.DEMON.CO.UK Backup: gmh@wdcc1.bnsc.rl.ac.uk WORLD WIDE WEB http://www.theastronomer.org ------------------------------------------------------------------- CI CYGNI U. Munari et. al., (INAF Padova-Asiago) and others report on The Astronomer's Telegram 2732 that the symbiotic star CI Cyg is on a steep rise toward a second maximum in the major outburst phase it entered in 2008 (Munari et al. 2008, CBET 1487), the first one after 30 years of flat quiescence. It has experienced only a few outbursts in its long recorded history. The outbursts of 1911 and 1937 were modest in both brightness amplitude and duration. Then, between 1970 and 1978 CI Cyg experienced a major outburst phase, characterised by three maxima occurring on Nov 1971 (V=9.3), Nov 1973 (V=9.8) and Aug 1975 (?), (V=8.7) and minima (V=11.1) on Jun 1973 and Mar 1975. One further and sharper minimum, centred on Oct 4, 1975 (at V=11.1), was caused by a total eclipse of the outbursting component by the M5.5 III companion. The current outburst is a close copy of that in 1970-78. After a maximum at V=9.50V that occurred on the first week of October 2008, CI Cyg declined steadily and reached minimum brightness at V=11.0, B-V=+1.1 on March 2010. The time delay between maximum and minimum has been about 550 days, as for the 1970-78 event. At the time of the latter, a rise toward a second maximum started soon after the first minimum. The same is occurring right now, with CI Cyg currently on the rise toward a new maximum. The last measurement we collected gives V=10.44, B-V=+1.19on July 9, 2010. If the similarity with the 1970-78 active phase will be maintained, the second maximum around V=9.8 should be reached in a few weeks time. SUPERNOVA 2010dx IN NGC 7038 Discovery by the CHASE Project of a possible supernova (CBET 2314): SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010dx Jun 8.17 21 15 11.09 -47 13 34.3 17.4 36.4"E, 20.2"S SN 2010dx is also present in images taken on June 9.19 (at mag approximately 17.1) and June 1.28 (at mag approximately 17.0). SUPERNOVA 2010dy IN ANONYMOUS GALAXY Discovery by S. Leonin, Italy of a possible supernova (CBET 2317): SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010dy Jun 6.94 16 10 11.03 +00 45 07.6 17.9 9 "E, 5 "S Milisavljevic and R. Fesen, Dartmouth College, report confirmation based on low-dispersion optical spectraobtained with the 2.4-m Hiltner telescope on June 10.3 UT suggesting type-Ia near maximum. Guy M Hurst