Ludendorff Coronal Flattening Index of the Total Solar Eclipse on March 9, 2016

TL;DR

This study calculates the Ludendorff coronal flattening index during the 2016 total solar eclipse to predict solar cycle activity, indicating a lower activity level for the upcoming 25th cycle.

Contribution

It provides the first detailed measurement of the coronal flattening index during the 2016 eclipse and uses it to predict the upcoming solar cycle's sunspot activity.

Findings

Coronal flattening index at 2 solar radii is 0.16.

Predicted maximum sunspot number for cycle 25 is 70±65.

Solar activity for cycle 25 is expected to be lower than cycle 24.

Abstract

Ludendorff coronal flattening index of the Total Solar Eclipse (TSE) on March 9, 2016, was calculated at various distances in solar radius. As a result, we obtained the coronal flattening index $\left(\epsilon =a+b\right)$ at a distance of 2 solar radii is 0.16. The $24^{th}$ solar cycle phase based on the 2016 TSE event obtained -0.64 which showed the corona is pre-minimum type. Resulted coronal flattening index value gives a predicted maximum amplitude of the monthly sunspot number ($W_{max}$) for the $25^{th}$ solar cycle to be $70\pm65$. Therefore, the solar activity for $25^{th}$ solar cycle predicted to be lower than the current solar cycle, which has a maximum sunspot number value of 146 in February 2014