Sun goes cool

A video posted by NASA back in 2017 had already stated that the low point in sunspots could reach its peak in 2019-2020, which is now being witnessed
Sun goes cool

Solar lockdown theories have been doing rounds these days across various social media platforms spreading an undue panic about cold weather, crop loss, famines, earthquakes and volcanic eruptions. The scientific opinion, however, disagrees with these claims and here is an attempt to dismiss all apocalypse theories.

While humans are experiencing things that are decidedly not okay, the Sun is doing nothing unusual whatsoever. The Sun has a cycle that lasts between 9 to 14 years—typically 11 years on an average. The peak of this cycle is called solar maximum, when the Sun produces more electrons and protons as huge solar flares and coronal mass ejections. And then, every 11 years or so, the sunspot activity fades away, bringing a period of relative calm. This is called the solar minimum and it is a regular part of the sunspot cycle. 

The solar cycle is based on the Sun's magnetic field, which flips around every 11 years, with its north and south magnetic poles switching places. Although a great deal of research is going on but it cannot be ascertained with utmost confidence as to what exactly drives these cycles. Sunspots are an area of intense magnetic activity on the surface of Sun that appears as an area of darkness.

Sunspots are indicative of solar activity, giving birth to solar flares and coronal mass ejections (CMEs). Although sunspots seem like tiny specks, these are actually colossal in size.  Sunspots have been continuously counted each day since 1838, allowing solar scientists to describe a repeating pattern in the wax and wane of solar activity as the solar cycle. Currently, we're in solar cycle 24. We don't know precisely when the next solar minimum will occur, but we can broadly predict it.

A video posted by NASA back in 2017 had already stated that the low point in sunspots could reach its peak in 2019-2020, which is now being witnessed.  The sun is currently in a period of "solar minimum" which means that the activity on its surface has fallen sharply. In 2019, the Sun was blank for 77% of the time and this year, it has been blank for 76% of the time so far. Two consecutive years of record-setting spotlessness indeed adds up to a very deep solar minimum. 

However, the Sun will again reach the maximum in the mid-2020s, though, when exactly the sunspot frequency will peak can be left to guess. The last solar maximum was in 2013-14, although it was ranked among the weakest on record. The current record-breaking solar minimum is part of a longer pattern of wax and wane which is because that the Sun may have been in a magnetic lull for the last 9,000 years or so. 

Astronomers like Dr. Tony Phillips assert that the sun's magnetic field has become weak, allowing extra cosmic rays into the solar system which may pose a health hazard to astronauts and polar air travelers, affect the electro-chemistry of Earth's upper atmosphere and may also trigger lightning. In an earlier article this year which was later amended,
NASA scientists  had feared that it could be a repeat of the Dalton Minimum, which happened between 1790 and 1830  so much so that in the year  1816 there was snow in  the month of July. However, let not any false fears play a sensational havoc since there are no convincing links between solar activity and climate variation. The global warming trend in the last decades cannot be explained in terms of solar activity because there has not been any trend in solar activity. Instead, the status of the Sun has a pronounced effect on the intensity and frequency of aurora. The more charged-up the solar wind headed towards Earth, the brighter and more frequent are the displays of Northern Lights and Southern Lights.

One way to gauge the solar activity is by looking at the Sun's mighty corona during a total solar eclipse when the Moon completely blocks the Sun's bright disk and gives a view of its hot outer atmosphere. Since the Sun's corona is typically flared and stretching away into space, it appears conspicuously around the limb of the Moon.  However, during solar minimum the corona is relatively small and tightly bound to the surface. All of this is well-timed for the next total solar eclipse in North America on April 8, 2024, since the Sun by then will be approaching its solar maximum.

Dr. Qudsia Gani is Assistant Professor, Department of Physics, Cluster University Srinagar

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