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AAVSO International Database

Special Notice #75: Monitoring of TT Ari in support of MOST observations

October 22, 2007: The Microvariability and Oscillations of Stars (MOST) Satellite will conduct a targeted photometric observing campaign on the cataclysmic variable TT Ari, beginning 2007 October 23 UT (JD 2454397) and concluding on 2007 October 28 (JD 2454402). This observing program was proposed by a group of Austrian amateur astronomers who proposed to the "MOST fuer Alle" program of the University of Vienna, the Austrian partner project of the MOST collaboration's "My Own Space Telescope" program for Canadian observers.

Special Notice #74: Sequence available for SN 2007le

October 17, 2007: Further to AAVSO Special Notice #73, "SN 2007le in NGC 7721", a comparison star sequence has now been added to the AAVSO Variable Star Plotter (VSP). The sequence by A. Henden was obtained at SRO based upon a single night of data; the calibration is estimated to have a zero-point accuracy of approximately 0.03 magnitudes.

Special Notice #73: SN 2007le in NGC 7721

October 15, 2007: SN 2007le was discovered in the galaxy NGC 7721 on October 13, 2007 by L.A.G. (Berto) Monard of Pretoria, South Africa (CBET 1100, Monard). The supernova has since been classified as a type-Ia, approximately 7-10 days prior to maximum (CBET 1101, Silverman et al.).

The coordinates of the supernova are:

RA: 23:38:48.41 , Dec -6:31:21.3 (J2000)

Special Notice #72: 1RXS_J023238.8-371812 rapid fading

October 12, 2007: A new large-amplitude cataclysmic binary, most likely a WZ Sge system, was discovered by K. Malek of the "Pi of the Sky" team in mid-September. It has been linked to the following ROSAT RASS object:

1RXS_J023238.8-371812

and has coordinates of

02:32:38.13 -37:17:54.7     J2000

It was about 11th magnitude upon discovery, and displayed superhumps with period 0.066d.

Special Notice #71: Next HST cataclysmic variable scheduled

October 11, 2007: The next HST object from Paula Szkody's program is scheduled to be observed during the week of October 29 through November 3. This is SDSS J074531.92+453829.5, another cataclysmic variable that is about V=19.1 at quiescence, and unknown brightness in outburst since it has never been observed to outburst. The coordinates are:

07:45:31.92 +45:38:29.5 J2000

and the AAVSO Harvard Designation and name is

0738+45 SDSS074545

Special Notice #70: Brightening of the symbiotic star AG Draconis

October 3, 2007: It was reported in CBET 1091 by U. Munari et al. that the symbiotic star AG Draconis is again in outburst following the decline from its April 2006 bright outburst. They note that the decline apparently halted on 2007 July 07, and has since brightened steadily. Their observations place AG Dra at V = 8.98 on 2007 September 30.8 UT (B = 9.69 and B-V = +0.71). They also note the presence of strong hydrogen and helium emission lines.

Special Notice #65: Support for HST Observations of PQ Andromedae

September 10, 2007: We have been informed by Dr. Paula Szkody that science observations of PQ Andromedae with the Hubble Space Telescope have been scheduled for this coming Wednesday, September 12, 2007 and Thursday, September 13, 2007 (UT). Dr. Szkody requests intensive coverage of this object through the night of September 11/12, 2007 (Tuesday/Wednesday UT) which is when the final decision will be made on whether PQ Andromedae is in quiescence and is deemed safe to observe.

Special Notice #63: Outburst in HS 2331+3905 [V455 And]

September 4, 2007: The WZ Sge-candidate object HS 2331+3905 [V455 And] has been reported in outburst on VSNET by two observers. This object was last reported as fainter than 14.6 on JD 2454347.3931 (Sept 3, 2007, 21:26 UT), and has now been detected at 14.59 and 14.4 by observers in Japan. HS 2331+3905 has never been observed in outburst before, and observations are strongly encouraged.

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