News and Announcements
|29 April||Mira Variables with Period Changes||
Mira variables are the longest-observed class of stars for which we have long-term quantitative data that allow us to study their behavior over centuries-long periods of time. Fortunately for us, they're also easy to observe and monitor, having some of the largest amplitudes of all variables, and hundreds of them are bright enough that they're within reach of astronomers with modest telescopes.
|28 April||AAVSO Joins Virtual Observatory VOEvents Stream||
Its an old story that astronomy is being drowned in data and its only getting worse. We have needed a "central clearing house" of sorts and the Virtual Observatory aims to be one solution in this vein.
Astronomers have also experimented with various methods of alerting interested people as to events as they happen and when they need to be followed up on. This is the concept behind VOEvents.
|28 April||Alert Notice 439: Correction to AAVSO Alert Notice 438 on SN 2011by||
April 28, 2011: In AAVSO Alert Notice 438 on Supernova 2011by in NGC 3972 (issued 2011 April 28), the position was attributed to the wrong object. Here is the corrected text:
|28 April||AAVSO Alert Notice 438||
SUPERNOVA 2011by in NGC 3972 = PSN J11554556+5519338
|27 April||New ejaavso preprint "Leo5 is a Z Cam Type Dwarf Nova" by P. Wils, T. Krajci, and M. Simonsen||
ej 142: "Leo5 is a Z Cam Type Dwarf Nova" (P. Wils, T. Krajci, M. Simonsen)
|20 April||Visual Observing Manual updates||
The Manual for Visual Observing of Variable Stars has been updated to reflect changes to the VSP and WebObs that happened when the new website was launched last summer. This mostly affects Chapters 2 and 7. To download these and other chapters, or the entire Manual, please click on the link below:
You will also find versions of the Manual translated into seven other languages on this page.
Stay tuned for the Portuguese verson, due to be completed soon!
|15 April||AAVSO Newsletter 48 now online|
|15 April||AAVSO Alert Notice 437||
Campaign to monitor the recurrent nova T Pyx throughout 2011 eruption
April 15, 2011: Further to AAVSO Alert Notice 436, a fast photometry observing campaign has been initiated by Dr. Bradley Schaefer (Louisiana State University) to monitor the recurrent nova T Pyxidis throughout its current eruption.
|14 April||Alerta de AAVSO 436||
Erupción de la nova recurrente T Pyxidis
|14 April||AAVSO Alert Notice 436||
Outburst of the recurrent nova T Pyx
|06 April||New ejaavso preprint: "Times of Minima and New Ephemerides..." by A. Marchini et al.||
ej 141: "Times of Minima for Several Eclipsing Binaries and New Ephemerides for V569 Lyrae, V571 Lyrae, and V572 Lyrae" (A. Marchini et al.)
|03 April||Alert Notice 435: V5588 Sgr = Nova Sagittarii 2011 No. 2 = PNV J18102135-2305306||
Apri1 3, 2011
Event: V5588 SGR = NOVA SAGITTARII 2011 No. 2 = PNV J18102135-2305306
Discovered by: Koichi Nishiyama, Kurume, Japan, and Fujio Kabashima, Miyaki, Japan
Discovery Date: ~ 2011 March 27.832 UT
Discovery Magnitude: unfiltered CCD magnitude mag 11.7 on two 40-s unfiltered CCD frames using a 105-mm f/4 camera lens (+ SBIG STL6303E camera)
Position: R.A. = 18:10:21.35, Decl. = -23:05:30.6 (equinox 2000.0)
|02 April||AAVSO Special Notice #238||
HST observations scheduled for GW Lib
|01 April||Charts and Sequences Update April 2011||
April 1, 2011
The following variable stars have either new or revised sequences and charts. If you observe any of these stars you should update your charts to the most recent version.
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