Hi David,

 Thank you for your interest in my paper.

   Venus does not have an intrinsic magnetic field but it has an induced magnetosphere which is the result of the interaction between a highly conductive body and the solar wind plasma. The solar wind carries a magnetic field, which is known as the Interplanetary Magnetic Field (IMF). Venus acts as an obstacle in the way of the solar wind flow and also the IMF. It is similar when a sphere is placed into a streaming flow (let's say water), it diverts the fluid and causes some interesting interactions.

   In space, the situation is a bit more complicated because of the presence of the magnetic fields in the solar wind. The magnetic field lines cannot pass through Venus very quickly so they start piling up ahead the planet (check Figure 7 in my paper, you can find it on my researchgate profile) and this leads to the formation of the induced magnetosphere.

   In the paper we studied what happens when the direction of the magnetic field in the solar wind changes very suddenly and very significantly (for example turning 180° within a tens of seconds). It means that the magnetic field lines will start piling up ahead Venus with opposite polarity (as compared to the conditions before the sudden rotation of the magnetic field) and as a further consequence the polarity of the induced magnetosphere will reverse as well (check Figure 7 in the paper). According to some previous studies the re-arrangement of the magnetic fields (e.g. polarity reversal of the Venusian induced magnetosphere) takes around 10 minutes.

The frequency of the polarity reversal depends only on the solar wind conditions. In our study we had complex selection criteria to search for polarity reversal cases and in the investigated 3.5 years period we found that it occurs on the average every 10 days. However, due to the 24 hour orbital period of the spacecraft we could survey the magnetic fields near Venus only at limited intervals (e.g. when the spacecraft was close enough to the planet) therefore it is definitely possible that we missed many events and the polarity reversal occurs even more frequently.

It is pointed out that the polarity reversal of the Venusian induced magnetosphere has nothing to do with the dynamics in the interior of the planet. This process is only driven by the solar wind conditions.

If you have any further questions, just let me know.

Best regards,

Daniel Vech

Thank you Sir!