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Z UMi

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  • 4 August 2024 at 4:56 pm #624083
    Gary Poyner
    Participant

    The RCB star Z UMi has started to fade.

    No clear nights in August yet for me, so the last measure is unfiltered and Tricolour Green from SLOOH…

    Selected observations…

    Jly 07.951 11.2 vis
    Jly 25.964 11.5
    Jly 28.929 11.8
    Aug 03.058 11.936C
    Aug 03.059 12.25TG

    This is the first fade since July 2019, and the period since recovery from that fade – September 2020 to present – is the longest unbroken maximum observed in Z UMi since my first observations of it began in 1994.

    Minimum is usually between magnitude 16.0-17.0V, but in 2007 Z UMi reached below magnitude 19.0C, and 18.5V in 2012.

    Observations are welcomed – visual, digital – and should be uploaded into the DB as soon as possible.

    Visual charts can be downloaded here

    CCD users may want to download a DSS chart from the AAVSO here

    Good luck,
    Gary

    Gary

    • This topic was modified 3 months, 2 weeks ago by Gary Poyner.
    6 August 2024 at 9:23 am #624146
    Mr Ian David Sharp
    Participant

    Hi all,

    Mag was 12.33 in V last night (05 Aug 2024) (average of 7 measurements).

    Cheers
    Ian.

    Attachments:

    1. 20240805_Z-UMI_V_PixelSkies-C11_IDS_plot_points.png

    21 August 2024 at 10:06 am #624391
    Mr Ian David Sharp
    Participant

    Hi all,

    My recent measurements in V show a very linear looking fade. I just added last night’s measurements.

    Cheers
    Ian

    Attachments:

    1. Z-UMi-20240821.jpg

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