2012 April 27 an invited review paper by P. Szkody and B. Gaensicke available in eJAAVSO now! Abstract- This paper presents a concise summary of our current knowledge of cataclysmic variables, including definitions of types and the observational basis for classification, what we have been able to piece together about evolution, and discoveries from recent surveys. We provide a list of unanswered problems and questions and references for seeking additional information. The importance of AAVSO observations in the past and for the future is highlighted. Download the paper here 2012 April 24 NEW Cataclysmic Variable Forum on the AAVSO website! 2012 April 21 New Nova in Sagittarius! PNV J17452791-2305213 A possible nova in Sagittarius was discovered by Stanislav Korotkiy (Ka-Dar Obs.) and Kirill Sokolovsky (ASC Lebedev/SAI MSU) on three images, obtained on 2012 Apr 21.01123UT with a wide-field survey camera (F=135mm f/2.0 telephoto lens and ST8300M unfiltered CCD, 30sec exposure time) at Ka-Dar Observatory's TAU Station, Nizhny Arkhyz, Russia (MPC COD C32). The object is clearly visible at magnitude 9.6 +/-0.3. The limiting magnitude of the images is ~14.0 (the scale is calibrated using V magnitudes of Tycho-2 stars in the field). Initial astrometry using nearby UCAC2 stars (RA, Dec, J2000): 17:45:28.03 -23:05:22.8 +/-1". The object is not visible on our previous images obtained on Apr 17.99UT (limiting mag. 14.0). The USNO-B1.0 catalog lists USNO-B1.0 0669-0621295 (magnitudes R1=16.21, B2=18.61, R2=18.65, I=16.62mag) just 0.6" away from the above position. The object could not be identified as a previously known one using MPChecker, AAVSO VSX and SIMBAD. Discovery images URL: http://www.astroalert.su/files/pnv_j17452791-2305213.jpg John Seach, NSW Australia, confirms there is a magnitude 8.8 object at the discovery position on a DSLR image taken with 50 mm f/1.0 lens. Image taken on April 21.654. Z CamPaign 2012 2012 April 15 It’s been 933 days since we launched the The response from AAVSO observers has been amazing. In fact, I have been concerned at times that the Z CamPaign has had an undue influence on the observing habits of AAVSO observers. Many who used to monitor a more diverse list of objects have concentrated their efforts on the stars in the Z CamPaign in lieu of other stars since the launch of the campaign. The result is that in 2 ½ years we have confirmed or determined, conclusively, the classification of 21 of the original 30 targets. 17 are definitively Z Cams, 4 are definitely not Z Cams, and the remaining 9 stars require further study to determine their type, although most are not likely to be Z Cams. Of those nine, V426 Oph and V513 Cas have proved to be particularly enigmatic. There is plenty of data, but analysis has not led to a determination of type. MN Lac is simply so faint that even the best CCD observers with 25-60cm telescopes are barely able to detect it at minimum. We dropped it from the campaign in year two, so data remains scarce. The others are just going to take a more concerted effort to unmask. Gary Poyner Reproduced with permission from the J. Br.Astron.Assoc. 122, 1, 2012 This story has something for everyone. Gary tells us the story of three historical novae, their discovery, characteristics and why they are still interesting today, from his viewpoint as a visual observer in heavily light-polluted Birmingham, England. | ACTIVITY AT A GLANCE New outbursts and unusual activity reported in the last 72 hours Last updated 15:22 UT, 2012 May 23 YYYYMMDD 20120523 V342 Cen ST Cha EU CMa HL Cma V1113 Cyg BC Dor CY Lyr HP Nor GS Pav DV Sco KK Tel HS2325+8205 20120522 TT Crt 20120521 FO Aql MU Cen V485 Cen WZ CMa DM CMa HO Del BX Pup UZ Ser V729 Sgr V730 Sgr SDSS J081207.63+131824.4 * indicates an unconfirmed outburst # indicates a noteworthy or unusual outburst 'Activity At A Glance' is gleaned from observations reported to AAVSO MyNewsFlash, BAAVSS-Alert, CVnet-Outburst, VSObs-share and VSNET-outburst. We sincerely thank all the observers who contribute timely observations and reports of activity to these email lists. Important to gather detailed long-term light curves for the
majority of these systems to better understand their nature.  AM Her stars in need of further investigation
RECENT PAPERS ON CVs For new papers on CV's see arxiv.org astro-ph Authors: Evans et al Authors: Shara et al Authors: Dunford et al Authors: Ringwald et al Authors: Barclay et al Authors: Shears et al Authors: Pyrzas et al Authors: Nelson et al Authors: Mukai et al Author: J. Echevarria Authors: Imamura & Tanabe Authors: Cohen et al Authors: Cannizzo et al |
