The AR3038 sunspot - now the largest on the Sun - has grown even larger overnight to become two and a half times the size of the Earth.
The Sun continues to approach the maximum of the current (25th since observations began) activity cycle, which is expected to be around 2025. New sunspots are appearing on the Sun and the largest, AR3038, is getting larger. Recently, it has suddenly grown larger, exceeding 30,000 kilometres across, said space weather monitoring portal Spaceweather.com.
Solar activity determines the movements of magnetic fields and fluxes of charged particles far around the star. This "space weather" can affect satellites and sometimes ground-based electronic and electrical devices. This is why scientists are constantly monitoring what is happening on the Sun, especially studying the behaviour of dark spots on its surface.
Spots on the Sun appear where the magnetic field lines exit. They slow down the movement of the red-hot plasma, resulting in areas of not-so-high temperature that appear dark. The number and activity of sunspots follows the 11-year cycle of solar activity: at times of minimum there may be none at all, while at highs the number may be in the tens or even hundreds.
Within a few days, weeks or months, they may "dissolve", disappearing imperceptibly. However, this process may be accompanied by an abrupt rupture and reconnection of magnetic field lines, resulting in powerful bursts of radiation and plasma streams released into space. In a matter of days, they reach the vicinity of the Earth, where they can cause auroras and geomagnetic storms, malfunctions in electronics and electrical systems.
For the time being, the AR3038 sunspot, which is "directed" towards our planet, poses such a threat. However, it is just north of the solar equator and is moving rapidly to the back side of the star, so that it should disappear from view completely in a few days.
In the meantime - and quite rapidly - the spot continues to grow. "Yesterday AR3038 was big. Today it is huge," writes Spaceweather.com. - This fast-growing spot has doubled in size in just 24 hours." Indeed, observations show that between June 20 and 21, the diameter of AR3038 increased to nearly 32,000 kilometres, becoming two and a half times the diameter of the Earth.
However, scientists do not expect any dangerous surprises from AR3038. According to them, the spot's energy is sufficient at most for an M-class flare. Such flares are not too rare and do not pose a serious threat to objects on the Earth's surface. At most, what can be expected are temporary problems with radio communications in the circumpolar regions of the planet and, of course, spectacular auroras.