Alert Notice 827: HP Lib being observed with HST

June 21, 2023

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Further to AAVSO Alert Notice 796, Dr. Anna Francesca Pala (European Space Agency, ESAC, Spain) informs us that observations of the cataclysmic variable HP Lib have been scheduled with the Hubble Space Telescope on:

2023 23 Jun 00:57:20 - 03:23:26 UT

Dr. Pala writes: "The monitoring is showing that the system is stable at V~13.5 and any data that you can collect tonight will be very valuable to verify that the system is safe to be observed with HST. Thanks for all your work  and good luck with the observations!"

Your V observations of HP Lib tonight are critical. Please continue nightly V snapshots through 2023 July 5.

HP Lib has a range of 13.55 - 13.8 V. The most recent observation of it in the AAVSO International Database shows it at magnitude 13.627 V +/-0.004 on 2023 June 19.3472 UT (G. Myers, Hillsborough, CA).

As usual, the positive V detection of the target the day before the HST observations is crucial in order for the HST team to approve their execution. Please see Alert Notice 796 for additional details and instructions.

Coordinates (J2000):  R.A.  15 35 53.07   Dec.  -14 13 12.2   (from VSX entry for HP Lib)

Charts with comparison stars for HP Lib may be created using the AAVSO Variable Star Plotter (VSP).

Please report observations to the AAVSO International Database using the name HP Lib. Reduce and submit observations as soon as possible after making them.

This Alert Notice was compiled by Elizabeth O. Waagen using information provided by Dr. Pala.


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