recurrent nova

Alert Notice 664: Monitoring recurrent nova U Sco to discover its imminent eruption

April 3, 2019: Dr. Bradley E. Schaefer (Louisiana State University) provides the following information:

"Frequent monitoring is requested of the recurrent nova U Scorpii over the next year or so to discover the upcoming very-fast eruption. The predicted outburst is for the year 2020.0±0.7. The eruption is likely within the next year, but it could well go off tonight.  

"Observers of many types are needed before the next outburst:

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.

Alert Notice 604: CI Aql observations must be reported by 14:45 UT 2017 November 1

October 31, 2017: Further to AAVSO Alert Notice 603, your positive observations of CI Aql, which will be used to determine whether the HST observation of CI Aql will take place, must be submitted to the AAVSO International Database by 14:45 UT (10:45 am EDT) on Wednesday, 2017 November 1. Without these positive ground-based observations reported by this time (and showing CI Aql not in outburst), the HST observation will not take place.

Alert Notice 599: CI Aql monitoring needed in support of HST observations

October 1, 2017 : Dr. Edward Sion (Villanova University) has requested AAVSO observers' assistance in monitoring the recurrent nova CI Aql in support of observations with the Hubble Space Telescope Cosmic Origins Spectrograph scheduled for October 30 - November 6, 2017. These observations are part of a study on short orbital period recurrent novae as Supernovae Type Ia progenitors.