Two Solar Cycles Active at Once

Posted: April 28, 2020 by oldbrew in Cycles, solar system dynamics
Tags: ,

.
.
Cycle 25 preparing to topple Cycle 24.

Spaceweather.com

April 27, 2020: Today, there are two sunspots in the sun’s southern hemisphere. Their magnetic polarity reveals something interesting: They come from different solar cycles. Take a look at this magnetic map of the sun’s surface (with sunspots inset) from NASA’s Solar Dynamics Observatory:

latest_4096_HMIBC_labelled_crop

One sunspot (AR2760) belongs to old Solar Cycle 24, while the other (AR2761) belongs to new Solar Cycle 25. We know this because of Hale’s polarity law. AR2760 is +/- while AR2761 is -/+, reversed signs that mark them as belonging to different cycles.

This is actually normal. Solar cycles always overlap at their boundaries, sprinkling Solar Minimum with a mixture of old- and new-cycle sunspots. Sometimes, like today, they pop up simultaneously. We might see more such combinations in the months ahead as we slowly grind our way through one of the deepest Solar Minima in a century.

The simultaneous appearance of two solar…

View original post 67 more words

Comments
  1. stpaulchuck says:

    pardon the OT post, but I have to say that I love coming to this site. It is an oasis of sanity in a devolving world of nutters, charlatans, and power mad pols. Thanks for being here.

    [reply] 🙂

  2. oldbrew says:

    Oulu neutron count is ‘very high’ today.

    Oulu Neutron Counts
    Percentages of the Space Age average:
    today: +11.0% Very High
    48-hr change: +0.1%
    Max: +11.7% Very High (12/2009)
    Min: -32.1% Very Low (06/1991)
    explanation | more data
    Updated 29 Apr 2020 @ 1800 UT

    spaceweather.com [date = Wednesday, Apr. 29, 2020]