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News and Announcements

27 June Two new eJAAVSO preprints: EBs in the 21st century; Transiting Exoplanets

(ej203): "Eclipsing Binaries in the 21st Century—Opportunities for Amateur Astronomers" by E. F. Guinan, S. G. Engle, E. J. Devinney

(ej204): "How Amateurs Can Contribute to the Field of Transiting Exoplanets" by B. Croll

25 June Alert Notice 462: Monitoring of J1407 for next extrasolar ring system transit

June 25, 2012: Dr. Eric Mamajek (Cerro Tololo Interamerican Observatory and University of Rochester) has requested AAVSO observers' assistance in monitoring the young star 1SWASP J140747.93-394542.6 to help determine the eclipse behavior related to a transiting ringed substellar companion.

This observing campaign begins now and continues until further notice. Dr. Mamajek writes:

22 June New eJAAVSO preprint: Amateur Observing Patterns and Their Potential Impact on Variable Star Science

(ej202): "Amateur Observing Patterns and Their Potential Impact on Variable Star Science" by M. R. Templeton

20 June New eJAAVSO preprint: "What Are the RCB Stars?"

(ej201): "What Are the R Coronae Borealis Stars?" by G. C. Clayton

19 June New eJAAVSO preprint: on AAVSO IT Infrastructure 1967-1997

(ej200): "An Overview of the AAVSO’s Information Technology Infrastructure From 1967 to 1997" by R. C. S. Kinne

19 June Three new eJAAVSO preprints

(ej199): "Long-Term Visual Light Curves and the Role of Visual Observations in Modern Astrophysics" by J. R. Percy

(ej198): "A Study of the Orbital Periods of Deeply Eclipsing SW Sextantis Stars" by D. Boyd

(ej197): "The AAVSO Widow—Or Should We Say Spouse?" by T. R. Williams

15 June New eJAAVSO preprint: RS Sge: The Search for Eclipses

(ej196): "RS Sge: The Search for Eclipses" by J. D. Horne

15 June Solar Bulletin - Volume 68, Number 5

The May 2012 Solar Bulletin is now available!

14 June APASS DR6 Press Conference Video

14 June Skin a Cat - Looking for period change in data

13 June New eJAAVSO preprint: on pulsation, dust production, and mass-loss

(ej195): "Variable Stars and the Asymptotic Giant Branch: Stellar Pulsations, Dust Production, and Mass Loss" by A. K. Speck

12 June New eJAAVSO preprint: Centennial highlights in astronomy

(ej194): "Centennial Highlights in Astronomy" by O. Gingerich

12 June Alert Notice 461: Nova Scorpii 2012 = MOA 2012 BLG-320

12 June 2012

10 June Alert Notice 460: Possible occultation by Pluto from US East Coast

10 June 2012: We have been asked to help disseminate the news of a possible occultation by Pluto visible to observers on the US East coast. Although the AAVSO does not ordinarily issue announcements of upcoming occultations, in this case the object is Pluto and the NASA New Horizons mission ( will be visiting Pluto in 2015.

09 June Charts and Sequences Update June 2012

The following stars have new or revised sequences since the last update April 23, 2012. Please update you charts as needed.


08 June Special Notice #286: Revised Timetable for June AE Aqr MAGIC Observations

8 June 2012: Dr. Christopher Mauche, Lawrence Livermore National Laboratory, has informed us that the timetable of MAGIC telescope  observations of the intermediate polar cataclysmic variable AE Aqr announced in AAVSO Alert Notice 458 has been revised. Here is the revised timetable for the dates in June:


2012 June
11, 1:43 - 2:26, UT
12, 1:39 - 2:22
13, 1:35 - 2:18
14, 1:31 - 2:34

07 June Capabilities of large visual data sets

07 June The AAVSO Strategy and Operations Survey Results

Survey Says - The AAVSO Strategy and Operations Survey

by Kevin Paxson

06 June Alert Notice 459: Monitoring of RU Peg requested for Swift observations

6 June 2012: Dr. Koji Mukai (Universities Space Research Association/NASA Goddard Space Flight Center) has requested AAVSO observers' assistance in monitoring the SS Cyg-type dwarf nova RU Peg in support of target-of-opportunity observations with the NASA Swift satellite during an outburst.

His observations will be targeted during the rise to outburst and during late decline from outburst. Thus, your prompt notification to AAVSO Headquarters of activity in RU Peg will be crucial to the success of this campaign.

01 June Through a Picket Fence - Overview of aliasing in data analysis


Grant Foster has written a new blog post titled "Through a Picket Fence". It describes the effect of aliasing when analyzing variable star data. It's written at an introductory level appropriate for those new to data analysis, but with brief references to the math more advanced people may find interesting. The post is at the URL below.

01 June New eJAAVSO preprint: "Miras"

(ej193): "Miras" by L. A. Willson and M. Marengo

31 May Special Notice #285: Outburst of old nova X Ser

31 May 2012: As announced by Robert Modic (Richmond Heights, OH) 2012 May 30 in the aavso-photometry discussion group ( and subsequently reported in vsnet-alert 14629, the old slow nova X Ser (Nova Ser 1903) is in outburst. This outburst is likely a dwarf nova-like outburst, similar to the one seen in 2009, which was the first reported since the nova outburst in 1903.

31 May New eJAAVSO preprint: Type 2 Cepheids in the Milky Way Galaxy and the Magellanic Clouds

(ej192): "Type 2 Cepheids in the Milky Way Galaxy and the Magellanic Clouds" by D. L. Welch

29 May Solar Bulletin - Volume 68, Number 4

The April 2012 Solar Bulletin is now available.

26 May Special Notice #284 - NOVA OPHIUCHI 2012 No. 2 = PNV J17395600-2447420

26 May 2012IAU CBET 3124 (Daniel W. E. Green, ed.) announces the discovery by John Seach (Chatsworth Island, NSW, Australia) of a nova in Ophiuchus on 2012 May 19.484 UT at magnitude 10.5 (digital SLR camera + 50-mm f/1.0 lens). Seach reports nothing is visible at this position on the Digitized Sky Survey. The object was designated PNV J17395600-2447420 when it was posted on the Central Bureau's TOCP webpage (

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