Alert Notice 839: BF Eri monitoring requested in support of HST observations this week

Note: HST was not able to observe BF Eri in November. It may be rescheduled for 2024 - stay tuned to the forums below for updates. An Alert Notice will also be sent when/if BF Eri is scheduled again.  -  Elizabeth O. Waagen, December 5, 2023

November 4, 2023

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Further to AAVSO Alert Notice 838, Dr. Anna Pala (European Space Agency, ESAC, Spain) informs us that observations of the cataclysmic variable BF Eri have been scheduled with the Hubble Space Telescope for:

2023 November 10  02:58:57 - 07:05:35 UT

Nightly V snapshots are requested from now through two weeks after the HST observations take place.  V observations will be critical in the few days before the HST date; a positive V observation is required 24 hours before the HST observations (i.e. November 9), in order for the HST team to finally approve their execution.

BF Eri has a range of 12.3 - 15.2 V. The most recent observations of it in the AAVSO International Database show it at V magnitude 15.133 +/- 0.022 on 2023 Nov. 1.38786 UT (D. Bailey, Sandia Park, NM) and 14.972 V +/- 0.0018 on Nov. 1.462419 UT (T. Rutherford, Blountville, TN).

Please see Alert Notice 838 for additional details and instructions.

Coordinates (J2000):  R.A. 04 39 29.95    Dec. -04 35 58.9    (from VSX entry for BF Eri)

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

Please report observations to the AAVSO International Database using the name BF ERI. 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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