Päikeseplekid

Päikeseplekid, also known as sunspots, are temporary phenomena on the photosphere of the Sun that appear as dark spots compared to the surrounding regions. They are caused by intense magnetic activity, which inhibits convection and results in reduced surface temperature, making them appear darker. Sunspots are typically associated with active regions on the Sun, which are areas of intense magnetic activity.

The number of sunspots visible on the Sun varies over an approximately 11-year cycle, known as the solar cycle or sunspot cycle. This cycle is marked by periods of high and low solar activity, with the number of sunspots reaching a maximum during the solar maximum and a minimum during the solar minimum. The solar cycle is not perfectly regular and can vary in length and amplitude.

Sunspots are of great interest to scientists because they are indicators of solar activity and can have significant impacts on Earth. For example, solar flares and coronal mass ejections, which are often associated with sunspots, can disrupt satellite communications, power grids, and even pose risks to astronauts in space. Additionally, the solar cycle has been linked to variations in Earth's climate, although the exact mechanisms are still not fully understood.

Sunspots were first observed by Galileo Galilei in 1610, and their study has since contributed to our understanding of the Sun and its influence on the solar system. Modern observations of sunspots are made using ground-based telescopes and space-based observatories, such as the Solar Dynamics Observatory, which provide detailed images and data on these fascinating solar phenomena.