Powerful and sudden geomagnetic storm surprises the Earth

A storm geomagnetic has surprised the Earth in the past few hours. The Earth’s magnetic field is still suffering the effects of yesterday’s impact of a cloud of solar plasma, a coronal mass ejection (CME). “It produced an unexpectedly strong geomagnetic storm,” we read on the specialized website SpaceWeather.com, edited by astrophysicist Tony Phillips. “The first contact with the CME was unremarkable, the storm did not begin immediately. Subsequently, however, the solar magnetic fields in the CME’s wake became connected to the Earth’s magnetic field. The storm has begun and it has quickly intensified. Storm levels have reached G3” around 9pm Italian time.

This short but intense event produced auroras red at mid-latitudes. Dan Bush captured the show from Albany, Missouri (latitude +40N).

“The show lasted more than an hour around 10:00 UTC,” said Dan Bush. “The red color was not visible to the naked eye, but it was easy to capture for my sky surveillance camera“.

Bush was not certain at that moment whether it could be red auroras or, instead, a SAR arc. “Red SAR arcs are caused by the loss of thermal energy into the atmosphere from the Earth’s ring current system,” explains SpaceWeather.com. Instead, it is about “authentic red auroras. Form and dynamics are crucial“.

The storm is now losing intensity, but this may only be a brief respite.

New geomagnetic storm warning, more CMEs on the way

The CME impact that occurred in the last few hours could be the first of a series. Several faint CMEs that left the Sun earlier this week are broadly on a collision course with Earth. None of these are particularly fast or powerful,”but their collective effect could cause several geomagnetic storms starting April 21st,” SpaceWeather.com points out.

What is a coronal mass ejection (CME)?

A’coronal mass ejection (CME) is a massive emission of matter from the solar plasma in the corona, the outermost region of the Sun. These events are often associated with intense magnetic phenomena, such as solar flares. When the Sun’s magnetic field undergoes intense changes, there is a strong acceleration of charged particles, which can be protons and electrons, within the solar corona. These particles are ejected into interplanetary space at very high speeds, even reaching several million kilometers per hour.

CMEs can greatly affect the space environment around Earth. When they hit Earth’s magnetosphere, they cause geomagnetic storms, with potential consequences such as communications blackouts, damage to orbiting satellites and disruptions to navigation systems. Furthermore, charged particles can also pose a risk to astronauts and space equipment.

What is a geomagnetic storm?

A storm geomagnetic is an alteration in the Earth’s magnetic field caused by an increase in interactions between the Sun’s magnetic field and that of the Earth. The classification of geomagnetic storms by the Space Weather Prediction Center (SWPC) from the NOAA is based on a scale ranging from G1 (minimum) a G5 (maximum), where G3 represents a storm of moderate strength.

G3 class storms are associated with increased solar activity, such as the arrival of a particularly powerful CME (coronal mass ejection). During a G3, effects such as increased currents induced in the Earth can occur, which can overload power grids and transformers, leading to temporary blackouts. Additionally, there can be interference in radio communications and GPS systems, increasing the risk to astronauts in orbit.

What is the red aurora and why is it special

L’red dawn it is an atmospheric luminous phenomenon that occurs near the Earth’s magnetic poles during geomagnetic storms. Contrary to the more common shades of green, rose or violathe red aurora appears as a distinct band red in color stretching into the night sky.

Its origin is linked to particular composition chemistry of the atmosphere and the high energy of solar particles. When charged particles from the solar wind hit Earth’s atmosphere, they excite oxygen and nitrogen atoms at high altitudes. Red auroras are caused by the excitation of oxygen atoms at altitudes above 200 km, while the most common auroras occur between 80 and 150 km.

The presence of oxygen at high altitudes and the energy of solar particles are necessary for the red aurora to be produced, which is therefore rarer than other shades. This phenomenon is special not only for its beauty but also because it offers us aimportant window on the study of interactions between the solar wind and the Earth’s atmosphere, contributing to our understanding of the Solar System and atmospheric processes.