‘Equinox effect’ could supercharge auroras this March
This month might be the best time to spot the northern lights for nearly a decade, as the combination of the “equinox effect” and supercharged solar activity will make aurora more likely. However, the precise place and time of their appearance remains to be determined.
At 10:46 a.m. EDT (2:46 p.m. UTC) on Friday, March 20, the sun will cross the celestial equator, marking the spring equinox in the Northern Hemisphere and the autumnal equinox in the Southern Hemisphere.
The equinox effect
This “equinox effect,” which doubles the risk of auroral activity around the spring and autumn equinoxes, was first explained by scientists Christopher Russell and Robert McPherron in a 1973 paper in the Journal of Geophysical Research.
They argued that auroras were more likely in March and September because south-facing magnetic fields in the solar wind cancel out Earth’s north-facing magnetic field, making the solar wind easier to circulate. magnetic field lines. In fact, the door opens, allowing more charged particles that collide with oxygen and nitrogen atoms in the upper atmosphere to cause aurora.
The March equinox is coming solar maximum — the peak of the Sun’s 11-year solar activity cycle — is coming to an end. During solar maximum, the sun’s magnetism is at full strength. NASA, the National Oceanic and Atmospheric Administration (NOAA) and the International Solar Cycle Prediction Committee have indicated that the Sun probably had reaches solar maximum in October 2024but they added that it would not be possible to confirm this for months or years.
The sun’s magnetic intensity is calculated by counting sunspots (colder regions of the sun caused by a concentration of magnetic field lines) on its surface. The number of sunspots is now trending downward, with the UK Met Office stating in January that activity seems to be declining. That means fewer solar flares and, crucially, fewer coronal mass ejections – clouds of charged particles that can travel toward Earth to produce auroras.
According to NOAAAccording to the Space Weather Prediction Center, Solar Cycle 26 is expected to begin between January 2029 and December 2032, with solar activity likely to remain low during this period.
Will there be a noticeable equinox effect in March? Conditions could produce the best auroras until the mid-2030s, but that doesn’t mean we should expect to see them at more southern latitudes in the Northern Hemisphere.
Ultimately, it all depends on solar activity, and it’s difficult to predict in advance. While early February produced the most active sunspot of the current solar cycle – resulting in auroras at much lower latitudes than usual – this monster has since disappeared. Unfortunately, there is no way to know if a new one will emerge to take its place in time for the equinox.
