Scientists have now spotted at planet Mercury, a classic space weather event called a hot flow anomaly, or HFA, which has previously been spotted at Earth, Venus, Saturn and Mars. These hot flow anomalies are made of very hot solar wind deflected off the planet's bow shock.
Scientists have now spotted at planet Mercury, a classic space weather event called a hot flow anomaly, or HFA, which has previously been spotted at Earth, Venus, Saturn and Mars. These hot flow anomalies are made of very hot solar wind deflected off the planet’s bow shock. The gray line shows the standing bow shock in front of Mercury. The signature of material flowing in a vastly different direction than the solar wind — an HFA — can be seen in red at the upper right. Credit: NASA/Duberstein