The Sun

Solar Maximum and Minimum

Solar maximum and minimum

Solar highs and lows are related to solar cycles. A solar cycle is a period of 11 years during which the amount of spots, bursts and solar bumps vary.

The Sun works at a constant and orderly pace. The solar cycle is related to the appearance of sunspots. In the nineteenth century it was discovered that every 11 years mysterious spots appeared on the surface of the Sun. Today we know that sunspots indicate the maximum solar, that is, the time when the Sun has more activity.

Some cycles have maximums with many sunspots and activity. Other cycles may have very few sunspots and little activity. Scientists work hard to improve our ability to predict the strength and duration of solar cycles. These predictions can help you predict these solar conditions, called space weather.

Solar Maximum

The solar maximum is the period of maximum activity of the Sun during the solar cycle. During this phase the greatest amount of sunspots appears. In solar maximum contrasts with the solar minimum, which is the period of the cycle in which the activities of the star is minimal.

The solar maximum is precisely the period in which the lines of the solar magnetic field are more distorted due to the differential rotation of the star, which causes the equator to rotate faster than the poles, which gives a particular configuration to the magnetic field of the star. The Sun takes approximately eleven years to pass from one maximum to another and approximately twenty two years to complete a complete cycle (that is, so that the magnetic polarity of the star is the same).

The solar maximum is a favorable period for the passionate observers of the polar auroras, but it is not so for astronauts, who are at risk of being hit by solar radiation storms emitted by our star. During this phase, the large amount of solar radiation weakens even satellite-based telecommunications and satellite navigation systems such as GPS.

Solar Minimum

The solar minimum is the period of least activity of the Sun in the solar cycle. During this period, the activity of sunspots and eruptions tends to decrease, until it is almost absent for several consecutive days. The precise date of the minimum is obtained by measuring for twelve months the activity of sunspots in a period of apparent minor activity, therefore, the precise identification of the date can only occur six months after the actual date of the minimum.

The solar maximum contrasts with the solar maximum, during which hundreds of sunspots appear in the star's photosphere. Next solar minimum from 2020 to 2055. As in 1645.

Solar Minimum Characteristics

The solar minimum, being the period of least activity of the star, is also the period in which, due to the decrease in the amount of radiation emitted, the largest number of manned space missions is concentrated. During this phase, astrophysicists can predict with certain precision the following two solar cycles through the solar dynamo effect: if the lines of the solar magnetic field turn out to be quite intense they tend to twist more, causing the appearance, during the next maximum, of a large amount of spots, while a less intense dynamo effect will result in fewer spots. Through this process, the solar cycle with the maximum in 2013 could be one of the weakest of the Maunder minimum.

To confirm this hypothesis, there is the depth of the current minimum that for the SIDC center closed the month of August with an average of daily sunspots of 0.0 something that had not happened since 1913 (last weak cycle before the modern maximum). Currently, this minimum is the fifth deepest since 1849 (statistics based on days without points in the period between a maximum and the next).


Published: December 16, 2019
Last review: November 16, 2019