Shattering Shapley’s Universe
Exactly a century ago, on the night of October 5/6, 1923, Edwin Hubble’s photographic observations of a Cepheid variable settled the vexing question of the day: Our Milky Way is not the entire universe.
Cepheid
Special Notice #60: Upcoming primary eclipse of ASAS182612
August 20, 2007: As described in Alert Notice 351, we are running an extended campaign on the newly discovered eclipsing Cepheid ASAS 182611+1212.6. Doug Welch has reminded me that the primary eclipse is predicted to be around August 28 around 0130UT. However, the eclipses are many days long, and the binary light curve is continuously changing, so don't just observe on the 28th.
Alert Notice 529: Observing campaign on 5 variables in Cygnus
October 1, 2015: Dr. George Wallerstein (University of Washington) has requested AAVSO assistance in monitoring 5 variable stars in Cygnus now through December 2015. He is working to complete the radial velocity curves for these stars, and needs optical light curves for correlation with the spectra he will be obtaining.
Alert Notice 331: Monitoring requested on Cepheid variable 1320-02 W Vir
January 10, 2006
SUBJECT: MONITORING REQUESTED ON CEPHEID VARIABLE 1320-02 W VIR
Longtime AAVSO member and colleague Dr. George Wallerstein, University of Washington, has requested our assistance in monitoring the Cepheid variable W Vir in support of his scheduled observing later this month at Apache Point Observatory in Sunspot, New Mexico. Visual and CCD observations are requested. For PEP observers who can reach magnitude 10 or fainter, PEP-V observations are also requested.
Alert Notice 335: Recurrent nova 1744-06 RS Ophiuchi in outburst AND W Vir monitoring window extended to mid-April
February 13, 2006
SUBJECTS:
1. RECURRENT NOVA 1744-06 RS OPHIUCHI IN OUTBURST
2. W VIR MONITORING WINDOW EXTENDED TO MID-APRIL
1. RECURRENT NOVA 1744-06 RS OPHIUCHI IN OUTBURST
Object: 1744-06 RS OPH
Coordinates: R.A. 17h 50m 13.202s Dec. -06o 42' 28.48" (2000.0)
Alert Notice 351: Campaign for a New Eclipsing Cepheid
June 8, 2007
Name:
TYC 1031 01262 1
ASAS 182611+1212.6
1821+12B (Harvard Designation)
ASAS182612 (AAVSO name)
Discovered by:
Pojmanski, G., Pilecki, B., Szczygiel, D. 2005, AcA 55, 275
and
Antipin, S.V., Sokolovsky, K. V. and Ignatieva, T. I. 2007, astro-ph/0705.0605
Position (from Sonoita Research Observatory, UCAC2):
18:26:11.50 +12:12:35.0 (+/- 100mas)