News and Announcements
|18 June||Alert Notice 520: X-ray nova and LMXB V404 Cyg in rare outburst||
June 18, 2015: V404 Cyg, an X-ray nova and a low mass X-ray binary (LMXB) with black hole component, is undergoing its first reported X-ray and optical outburst since 1989. Large scale, rapid variations are being reported in wavelengths from X-ray to radio by professional and amateur astronomers worldwide.
|15 June||Alert Notice 519: Nova Sgr 2015 No. 2 fading as dust production rises||
June 15, 2015: Nova Sgr 2015 No. 2 (PNV J18365700-2855420; see AAVSO Alert Notice 512) is undergoing a significant fading visually as its infrared excess increases, indicating that substantial dust production is underway.
|12 June||Solar Bulletin - Volume 71, Number 05||
The May Solar Bulletin is now available. Please visit the Solar Bulletin web page to download your copy: http://www.aavso.org/solar-bulletin The May SID Data report is available here: www.aavso.org/sid-database
|08 June||Guía de Fotometría CCD de AAVSO disponible en español||
Gracias al gran trabajo de un equipo de voluntarios españoles liderados por by Juan-Luis González Carballo (GCJ) y Josep Lluís Salto González (SJGA), tenemos el agrado de anunciar que la versión en español de la Guía de Fotometría CCD de la AAVSO ya está disponible para bajar:
|08 June||The AAVSO Guide to CCD Photometry in Spanish||
Thanks to a hard-working team of volunteers led by Juan-Luis González Carballo (GCJ) and Josep Lluís Salto González (SJGA), we are pleased to announce that a Spanish language version of the AAVSO Guide to CCD Photometry is now available for download:
|02 June||New JAAVSO preprint: Synthetic and photometric mags for Sloan standard stars||
Comparison Between Synthetic and Photometric Magnitudes for the Sloan Standard Stars
|02 June||New JAAVSO preprint: Some personalities from variable star history||
Some Personalities from Variable Star History
|01 June||New JAAVSO preprint: Margaret Harwood and Maria Mitchell Observatory||
Margaret Harwood and the Maria Mitchell Observatory
James W. Hanner
Received Jaunary 15, 2015; accepted May 21, 2015
|27 May||New JAAVSO preprint: A binary model for emission line star FX Vel||
A Binary Model for the Emission Line Star FX Velorum
|27 May||New JAAVSO preprint: Early-time flux measurements of SN 2014J||
Early-Time Flux Measurements of SN 2014J Obtained with Small Robotic Telescopes: Extending the AAVSO Light Curve
|21 May||New JAAVSO preprint: delta Sct pulsation periods in KIC 5197256||
The δ Scuti Pulsation Periods in KIC 5197256
|20 May||New JAAVSO preprint: UXOR hunting among Algol variables||
UXOR Hunting among Algol Variables
Received February 18, 2015; revised March 31, 2015; accepted May 20, 2015
|19 May||Introducing the SID Data Grabber||
Thanks to a great volunteer effort by George Silvis, Sudden Ionospheric Disturbance (SID) observers can now use the SID Data Grabber help prepare an AAVSO SID report file from their Stanford/SARA superSID monitor log files. Please visit the SID Data Grabber page to read more and download this handy application.
|15 May||New JAAVSO preprint: Recent minima of 149 EB stars||
Recent Minima of 149 Eclipsing Binary Stars
|14 May||New JAAVSO preprint: Video Technique for Observing EB stars|
|13 May||New JAAVSO preprint: Sudden period change and dimming of V752 Cen|
|12 May||AAVSO Newsletter for April 2015 is published||
AAVSO Newsletter 64, April 2015 is now available to members
The AAVSO Newsletter is a periodic, general forum that supports our various observing programs with lists of new targets, observing programming ideas, and general information that spans a wide area of interest. Guest writers contribute pieces that can range from current events to book reviews.
|23 April||Annual Report for 2013-2014 is now online||
Annual Report of the AAVSO for 2013-2014
|16 April||Special Notice #403: GW Lib HST schedule set||
April 16, 2015: Further to AAVSO Alert Notice 513, Dr. Paula Szkody (University of Washington) informs us that the HST observations for the cataclysmic variable GW Lib have been scheduled for
2015 April 22 04:04:36 - 09:00:06 UT.
|16 April||Solar Bulletin - Volume 71, Number 3||
The March Solar Bulletin is now available. Please visit the Solar Bulletin web page to download your copy:
The March SID Data report is available here: www.aavso.org/sid-database
|15 April||Alert Notice 518: Observations of 2MASS J06593158-0405277 needed||
April 15, 2015: Dr. Fabienne A. Bastien (Hubble Postdoctoral Fellow, Pennsylvania State University) has requested AAVSO assistance in monitoring the rare FU Ori object 2MASS J06593158-0405277 as part of a campaign to observe this T Tauri star from the optical to the infrared in the coming weeks.
|13 April||Special Notice #402: RW Aur more intense monitoring needed now||
April 13, 2015: Further to AAVSO Alert Notice 514, the Chandra observations of the classical T Tauri star RW Aur (component A) have been scheduled and will take place
2015 April 16 6:30 - 17:37 UT
|03 April||Special Notice #401: AM Her NuSTAR observations April 5||
April 3, 2015: Further to AAVSO Alert Notice 517 (www.aavso.org/aavso-alert-notice-517), Dr. Axel Schwope (Leibniz Institute for Astrophysics Potsdam, Germany) informs us that the NuSTAR X-ray observations of AM Her will take place on
2015 April 5 15:35 UTC - April 6 19:15 UTC
These NuSTAR observations overlap with the XMM-Newton observations scheduled for April 6.
|02 April||Alert Notice 517: Monitoring of AM Her urgently requested in support of XMM-Newton and NuSTAR observations||
April 2, 2015: Dr. Axel Schwope (Leibniz Institute for Astrophysics Potsdam, Germany) has requested AAVSO observers' assistance in monitoring the magnetic variable AM Her in support of upcoming XMM-Newton plus NuSTAR (Nuclear Spectroscopic Telescope Array) observations.
The XMM-Newton observations are scheduled for 2015 April 06 02:37:02-15:07:02 UT. The NuSTAR observations have not been made final yet but are expected to run longer. A Special Notice will be issued when the NuSTAR schedule is known.
|02 April||Alert Notice 516: Nova Oph 2015 = PNV J17291350-1846120||
April 2, 2015
Discovered by: Yukio Sakurai, Ibaraki-ken, Japan
Discovery magnitude: 12.2 unfiltered, using 180-mm f/2.8 lens
Discovery date: 2015 March 29.766 UT
Coordinates: R.A. 17 29 13.58 Dec. -18 46 11.7 (2000.0)