Two coronal mass ejections (CME) that left the Sun last Sunday (14) and on Monday (15), are expected to hit Earth this Thursday (18), according to the National Oceanic and Atmospheric Administration (NOAA), from the USA.
Once they travel through space, the particles from the explosions can fuse together in a kind of “cannibalization” — which forms an even stronger CME. Cannibal CMEs contain entangled magnetic fields and compressed plasmas that can trigger strong geomagnetic storms.
On the NOA space weather scale, which runs from 1 to 5, the expected geomagnetic index for today is G3 — considered strong.
As a potential impact, weak electrical grid oscillations may occur and the aurora borealis may be visible in high latitudes such as Canada and Alaska.
The geomagnetic storm is expected to extend into tomorrow, but on a smaller scale. According to NOAA, the index must be G2.
Level G1 storms can cause weak fluctuations in the electrical grid, impact the operations of satellites and migratory animals, and even produce auroras.
Those classified as G2 are relatively more intense and can result in voltage alarms in high-altitude power systems and even cause transformer damage if they last too long.
They can also impact spacecraft operations and disrupt high-frequency radio propagation.
What are geomagnetic storms
A geomagnetic storm is a large disturbance of the Earth’s magnetosphere (a field that protects the Earth from interplanetary weather conditions) that occurs when there is a very efficient exchange of energy from the solar wind to the space environment around the planet, according to the Climate Prediction Center. Space, from NOAA.
These events result from variations in the solar wind that produce large changes in currents, plasmas and fields in the Earth’s magnetosphere.
The solar wind conditions that are effective in creating geomagnetic storms are sustained (for several or many hours) in periods of high-velocity solar wind and, more importantly, a southward-directed solar wind magnetic field (opposite to the direction of the solar wind). of Earth) on the day side of the magnetosphere.
In this case, the condition is effective to transfer energy from the solar wind to the Earth’s magnetosphere.
The biggest storms that result from these conditions are associated with solar coronal mass ejections — where about a billion tons of plasma from the Sun, with its embedded magnetic field, reach Earth.
Typically, CMEs typically take several days to reach Earth, but it has been observed that in some of the most intense storms, they arrive within 18 hours.
Source: CNN Brasil