Alert Notice 651: Monitoring of T Pyx needed for HST observations

September 27, 2018: Dr. Ed Sion (Villanova University) requests AAVSO observers' assistance in monitoring the recurrent nova T Pyx, beginning immediately, in support of upcoming HST observations.

The HST COS observations have been scheduled to take place during the window of 2018 October 4 - 6. It is essential to know the status of T Pyx in order for the HST team to safeguard the instrumentation and make a final decision about approving the COS observations.

Beginning immediately, please observe T Pyx in V one to two times per night; V is preferred to other filters or unfiltered. Visual observations are welcome. It is particularly important to have positive observations available to the HST team from the nights of October 2/3, 3/4, 4/5, 5/6, and 6/7; they will make their decision 24 hours before the scheduled observation time. Please continue nightly V snapshots until October 15.

Please submit observations as soon after making them as possible to the AAVSO International Database. If T Pyx appears to be going into outburst, report observations immediately and email AAVSO ( T Pyx is around magnitude 15.5 V at minimum, and can brighten to magnitude 6 in outburst. Observations brighter than 14.0-14.5 should be treated as a possible outburst beginning.

Coordinates:  R.A. 09 04 41.51   Dec.  -32 22 47.6   (2000.0)

Charts with a comparison star sequence for T Pyx may be created using the AAVSO Variable Star Plotter (VSP).

Please submit observations to the AAVSO International Database using the name T PYX.

AAVSO Forums: T Pyx is the topic of the AAVSO Campaigns and
Observations Reports forum thread

and the AAVSO Novae forum thread

This AAVSO Alert Notice was compiled by Elizabeth O. Waagen.

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