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Ed Wiley Catches V1060 Cygnus Outburst Aug-Sept

Inspired by Bill Dillon's work on dwarf novae, Ed began a program of imaging these cataclysmic variables in Cygnus. Just at the beginning of the observing program, V1060 Cyg went into outburst . Around 3 Septemeber it seemed to be decreasing in magnitude, which is typical for an SS Cyg CV. Then it began increasing in magnitide, which is unusal for this kind of variable. It faded to its reseting state around 13 September. Ed has posted a crude light curve. Note that the check star variation is good, with a standard deviation over all points of 0.05, decreasing to 0.03 when three outliers are disregarded.

TU Ind outburst caught by Bill Dillon 4 July 2007

Using GRAS006 in Australia, Bill Dillon was the only observer to catch the 4 July 2007 outburst of Tu Ind, a "Dwarf Nova" of the U Geminorum class of nova-like variables. This variable is poorly positions (-45degrees) for observation from Mayhill, but superbly positioned from Australia. Bill began his sequence on s July 2 UT, and ended on July 8 UT (only July 3 UT is missing). The star was in outburst on the 4th, then gradually faded. The image is cropped, so the square is about 8 arcminutes or so on a side (north at the top, west on the right). The star varies from about 14th to 17th magnitude.

Data:

Date, Magnitude, Filter, Scope, exposure (total)

JUL 08.6515, 16.7, V, GRAS-AERO6: Australia, 12m-exp
JUL 07.6260, 15.37, V, GRAS-AER06: Australia, 10m-exp
JUL 06.6502 ,14.84, V, GRAS-AER06: Australia, 6m-exp, fading
JUL 05.6962, 14.38, V, GRAS-AER06: Australia, 6m-exp
JUL 04.7065, 14.33, V, GRAS-AER06: Australia, 6m-exp
JUL 02.7131, <17.0, V, GRAS-AER06: Australia, 6m-exp
JUN 28.7871, <17.0, V, GRAS-AER06: Australia, 6m-exp

Darks and Bias Frames Posted

Ed is taking dark and bias farmes and posting them on the

server for use by our observers. He would be interested to know if these are of use to the variable observers. If so, the practice will continue: Standardized 120 and 180 second exposures for G1,2 and 4 with 10 bias frames per scope.

Chris Norris has completed CCD tests for AREO 1, 2, and 4. Results can be downloaded as a PDF and are excellent, image with confidence!

Working with Landolt fields, Ed Wiley has found that AREO1 with V-filter can reach SNR = 100 for stars to about 14.1 magnitude in a 120 second exposure. The same SNR values can be reached with the I and R filters in a 60 second exposure.

Links

American Association of Variable Star Observers. The largest North American organization, lots of resources. Publishes JAAVSO, news letters, observing manuals, etc.

The Webb Society. A British organization with lots of resources. Publishes observers manuals, the famous Observers Guide series, the Deep Sky Observer, with both variable and double star papers as well as observing tips and other papers.

AAVSO list of international variable star groups. Find a group in your country!