For the first time in more than a month, the Sun suffered an X eruption, the strongest type there is. The event, which occurred in the AR3663 sunspot group at 11:22 pm (Brasília time) on Thursday (2), was classified as X1.7.
As a result, the radiation ionized the top of Earth’s atmosphere, causing a severe R3 radio blackout (on a scale ranging from R1 to R5) in an area over the Philippine Sea, south of Japan, Australia, and much of from China.
Let’s understand:
- The Sun has an 11-year cycle of activity;
- It is currently in what astronomers call Solar Cycle 25;
- This number refers to cycles that have been closely monitored by scientists;
- At the height of the solar cycles, the star has a series of spots on its surface, which represent concentrations of energy;
- As magnetic lines become entangled with sunspots, they can “pop” and generate gusts of wind;
- According to NASA, these bursts are massive explosions from the Sun that shoot radiation-charged particles out of the star in jets of plasma (also called “coronal mass ejection” – CME);
- Flares (flares) are classified into a letter system by the US National Oceanic and Atmospheric Administration (NOAA) – A, B, C, M and X – based on the intensity of the X-rays they release, with each level having 10 times the intensity of the previous one;
- Class X, in this case, denotes flashes of strong intensity, while the number provides more information about their strength;
- An X2 is twice as intense as an X1, an X3 is three times as intense, and so on.
According to the space observation guide EarthSky.orglast night’s flare marks a peak in recently observed activity in that region, which has been growing in size and magnetic complexity, making it the only one to show a high-potential beta-delta configuration.
A CME is expected to be released from the explosion site. Confirmation awaits new data from the Solar and Heliospheric Observatory (SOHO), which is operated in partnership between NASA and the European Space Agency (ESA).
Read more:
Double CME triggered by the Sun disrupts Earth’s magnetic field
A few hours before this extreme event, an unexpected G3 geomagnetic storm (considered strong on a scale ranging from G1 to G5) hit Earth. Starting at 2:59 pm and extending over two three-hour periods, the event was triggered by two CMEs of previously unknown origin.
As a consequence of the disturbance of the Earth’s magnetosphere, auroras have been observed as far south as Washington, in the USA.
According to the meteorology and space climatology platform Spaceweather.comanother CME is expected to reach the Earth’s magnetic field on Saturday (4), which could cause a G1 (weak) geomagnetic storm and produce auroras in the extreme north of the globe.
What are auroras?
An optical phenomenon that occurs at extreme latitudes on the globe, the aurora (borealis, when formed in the north and austral, when it is formed in the south) is often visible to the naked eye and is seen in the night skies.
If the solar wind is facing Earth, the planet’s magnetosphere deflects most particles, although some can penetrate the atmosphere by following magnetic lines, especially in polar regions. When doing so, the particles react with molecules present there, producing auroras.
Although they generally have a milky greenish color, these lights can also display shades of red, blue, violet and pink.
