Skip to main content


Special Notice #265: Bright Symbiotics in Sgr, Cyg, and Oph

March 3, 2012: Observer S. O'Connor reported late last week that the symbiotic stars V4018 Sgr, CH Cyg, and V2523 Oph all appeared to be in outburst or brighter than normal.  He reports: V4018 Sgr at V=11.59 on JD 2455981.021 (2012 Feb 23.521); CH Cyg at V=7.30 on 2455982.976 (Feb 25.476); and V2523 Oph at V=11.67 on 2455981.0 (Feb 23.5).  Other more recent visual observations of CH Cyg by G. Holmberg (vis=7.6 on 2455983.4993) and D. Barrett (vis=7.4 on 2455985.6013) confirm the star is well above magnitude 8.0 at this time.


Approximate wavelengths for filters accepted for the AAVSO International Database

The filters listed below are used in the AAVSO International Database. For your reference, the approximate effective wavelength is given as well as the Full Width Half Maximum. These filters may be used when submitting observations to the AAVSO via WebObs.

Charts and Sequences Update November 2011

 Dear AAVSO Observers,

The following charts and sequences have been revised since the last update September 29, 2011. This batch of updates includes many stars from the YSO Section Observing Program, as well as stars visible only from the southern hemisphere.

There are also several updated sequences for HMXBs and WR stars from Gordon Sarty's HMXB Campaign.

Modern observations of Hubble's first-discovered Cepheid in M31

The paper "Modern observations of Hubble's first-discovered Cepheid in M31" has been accepted for publication to PASP, and is now available on

PEP Newsletter v18n1

Message from the Editor

Once again, photoelectric photometry was well represented at the AAVSO Fall Meeting, held this year in Chicopee and South Hadley MA, with Tom Dennis and Ron Zissell as hosts.

PEP Newsletter v17n2

Photoelectric Photometry Newsletter, Vol. 17, No. 2
April 1997
J. Percy, editor


Special Notice #256: Request for fast optical time series of SN 2011fe

September 16, 2011: Dr. Bradley Schaefer (LSU) requests fast time series of SN 2011fe over the next several weeks to attempt the detection of fast optical variations in supernova light.

The following request was prepared by Dr. Schaefer which we forward at his request:

Supernova Photometry Chat with Dr. Michael Richmond

On 13 September, 2011, we had the good fortune to have Dr. Michael Richmond, Physics Professor and Observatory Director for the Rochester Institute of Technology in New York chat with us about SN 2011fe and supernova photometry in general. Here is the transcript from that chat session.

Special Notice #253: Request for Observations of MAXI J1836-194

September 10, 2011: Dr. Gregory Sivakoff (U. of Alberta) requests observations of the X-ray binary star MAXI J1836-194 as part of the JACPOT collaboration studying stellar radio jets from compact binaries.  There is no predetermined duration for this campaign, but observations are requested now to coincide with ongoing X-ray and radio observations.


AAVSO 49 Bay State Rd. Cambridge, MA 02138 617-354-0484