2725: Sunspot Cycle

2023-01-18T03:34:18Z

Aeiaml: Fixed a grammatical error.

{{comic
| number = 2725
| date = January 16, 2023
| title = Sunspot Cycle
| image = sunspot_cycle_2x.png
| imagesize = 740x503px
| noexpand = true
| titletext = Who can forget the early 2010s memes? 'You know you're a 90s kid if you remember the feeling of warm sunlight on your face.' 'Only 90s kids remember the dawn.'
}}

==Explanation==
{{incomplete|Created by a NINETIES KID WHO ATE THE SUN - PLEASE change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic is a reference to the {{w|solar cycle}}, which is a roughly 11-year cycle of changes in the Sun's activity from a period of minimal levels of various related phenomena ({{w|sunspots}}, solar radiation, ejecta, and solar flares) to one of maximum activity in these areas. As the cycle continues, the Sun returns to minimal activity and starts over. Without actually studying the Sun, however, there is no discernable difference to our daily lives here on Earth, and studying the Sun in enough detail is difficult due to its intrinsic and eye-damaging brightness whenever viewed directly. The comic may be a joke that nobody ever looks outside anymore, and so it may be possible to convince people that the sun has gone away.

This comic makes a joke that when the absolute number of sunspots appears to decrease it is not because they disappear, but because they get so crowded that they begin to merge, and thus the number of individual spots decreases whereas the area of the sun covered by sunspots continues to increase to near total 'darkness'. This causes there to be a completely dark Sun after 11 years, at which point any new sunspots are ''bright'' patches, and the next 11-year cycle repeats the process but accumulating bright spots until eventually it is all bright once more, giving a total bright/dark cycle of 22 years.

The curve showing the number of differentiable sunspots in this 22-year cycle would follow the curves for two whole cycles of our normal Sun, as the number of distinct spots (of either kind) decreases down to practically just one Sun-enveloping spot. The change in brightness over the cycle, however, repeats only over the full 22 years, darkening and then being made to shine bright once more as the other type of spot appears and begins to dominate once more.

Below is a graph showing the number of sunspots as a function of time from around 1965 to 2025. Periods where the sun is dark are shown with black under the curve, and in transition periods with lines of darkness getting closer together on the way to 'fully' dark area plus vals of light reinserting themselves in the lightening part of the cycle. Also for clarity the troughs are labeled with the sun being bright or dark. It is always when there are few spots that the sun is either completely free from spots and thus bright, or completely covered and thus dark. The maxima are always during the height of the transition between the two extremes, with a wide swathe of the time around the minima being mostly light or mostly dark, alternating at around a decade of each predominating.

At times, this closely synchronises with the calendar decades. From this curve it can be seen that the Sun was bright across the 1990s, but not in the dark 1980s or the dark time from around 2001 to 2014. This fact is mentioned in the title text (see below). Similarly the 1970s were mostly bright, after the largely dark 1960s, the width of the transition periods covering the marked decade-defining years in slightly offset ways compared to the neighbouring ones. After the darkness began around 2000, the shift was such that it finally got bright again around 2014, with darkness returning around 2024. This is because of the sunspot cycles being 11 years (making the illumination cycle 22 years) and eventually it no longer credibly meshes with the arbitrary decadal cut-offs.

All this would obviously be catastrophic if it happened in our version of the universe, as during a dark phase insufficient light would be coming from the Sun, and the Earth could freeze if all the energy from the Sun was reduced. If the spots only affect light in the visible spectrum, then Earth would not freeze but plants would have trouble with photosynthesis and other natural processes would be interrupted. In our universe sunspots cool the area of the Sun where they appear, relative to the rest of the surface (50-75% of the nearly 6000K 'norm'), but they are far from being actually dark; [https://image.gsfc.nasa.gov/poetry/workbook/sunspot.html NASA says] that each sunspot on its own would glow orange, brighter than the Moon is when it is full (with a typically bright Sun illuminating it). So even in a completely sunspot-covered Sun, the Sun would still be brighter than the Moon ought to be, and far brighter than the dark-time Moon would become (possibly causing issues for nocturnal life, as well). It would be possible to see it (and see by it) even if the heat delivered were very low and even at noon it would seem to be {{wiktionary|crepuscular}} by our normal expectations. See more in the title text explanation.

These problems are obviously not a serious threat in the reality of the comic, as the Sun is truly dark and yet people and natural systems have long survived these dark periods and adapted accordingly. This becomes clear in the title text where internet memes indicate that people lived fine through the dark periods, although they obviously did not 'properly' see the Sun, as kids, if they were born during the early start of a 'dark decade'.

The title text indicates the effect on internet memes that the special solar cycle has had. During the 2010s in our universe there were many '90s kid' memes. Those were also popular in this universe, but they reflect that the Earth had at that time been dark since the 2000s, and thus only those born in the 90s and before would remember dawn or the feeling of the warm sun on their faces.

This of course indicates that the Sun is actually dark and gives no warmth. Thus it is a mystery how life on Earth prevails, but given that there were kids from the 1990s that made memes twenty years after, life does work in this strange alternate universe.

==Transcript==
:[This comics shows two graphs, one also with several images of the Sun in different times in the solar cycle. The top graph is much larger than the bottom graph, and above them is a explanation of what the graphs shows:]
:Ever wonder why the sun disappears for about 10 years every other decade? This terrifying period of worldwide darkness is a natural consequence of the 11-year sunspot cycle:

:[A graph is shown with a label above the arrow on the Y-axis and a label written above the left part of the X-axis with an arrow pointing from it to the right (there is no arrow on the X-axis line). The graph shows a sine curve with a dashed line. It starts close to the bottom and then increases, then decreases before it finally slightly increases again. Above the dashed line are eight circles representing the sun with various levels of sunspots, with an arrow between each circle pointing to the next to the right. All circles are just above the dashed curve and the small arrows between them also follow the curvature of the line, so this string makes the same shape as the curve. along the eight representation of the sun there are five labels. The eight Suns are described below with labels given when relevant.]
:Y-Axis: Sunspot number
:Y-Axis: Time

:[The first Sun's circle is completely white.]

:[The second Sun's circle has a few sunspots. A label is written to the left of it:]
:Dark sunspots appear

:[The third Sun's circle has several sunspots. A label is written to the left of it:]
:Sunspot number rises

:[The fourth Sun's circle is half covered in sunspots.]

:[The fifth Sun's circle is mostly black with a few lines of white dots. Between the fourth and fifth circle is a label:]
:Number falls as sunspots merge.

:[The sixth Sun's circle is almost completely black with just a few small white spots. A label is written above it:]
:Sunspots envelop sun, Earth enters years of darkness.

:[The seventh Sun's circle is mostly black with a few light areas.]

:[The eighth Sun's circle is still mostly black but with some larger white areas. A label is written above and left of it:]
:Bright sunspots appear, cycle reverses.

:[Below is a second graph with a label written near the top of the Y-axis which is otherwise not labeled. The X-axis also has no label, but six years are written beneath at equal intervals. The graph shows a similar sine curve as the one above, but with almost five cycles shown. Also, each cycle is not close to being a perfect sine curve, but has the property with a peak followed by a trough. The five troughs are labeled. The area beneath the curve alternates from being black and white when there is a trough, with the peak in between having several vertical lines, indicating transfer from black to white and vise versa. There are not same distance between peaks and there are also features on the graphs, for instance the two peaks in the middle has a drop, so they look like volcanoes. And the last full peak has a clear outlier year with many sunspots.]
:Label: History:
:X-axis labels: 1970 1980 1990 2000 2010 2020
:Through 1970-1980: Sun is bright
:Through 1980-1990: Sun is dark
:Through 1990-2000: Sun is bright
:Through 2000-2010: Sun is dark
:Through 2010-2020: Sun is bright

{{comic discussion}}

[[Category:Astronomy]]
[[Category:Timelines]]
[[Category:Line graphs]]
[[Category:Internet]]

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2725: Sunspot Cycle