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A total {{w|solar eclipse}} occurred in North America {{w|Solar eclipse of April 8, 2024|on April 8, 2024}}, a week after this comic. A solar eclipse occurs when the Moon moves between the Sun and the Earth, but in order for it to be a total eclipse, the Sun, Moon and the observer's position on the Earth need to line up nearly exactly, and at the right distances (if the Moon is too far away, the eclipse will be annular, rather than total). When such a phenomenon occurs, there's a "path of totality", referring to the range of locations where such an alignment occurs (though only for a few minutes in each location). Away from, but near to, the path of totality (and outside of the specific time of totality), the Moon partially obscures the Sun. In Boston, where [[Randall]] lives, the Sun will be 93% obscured at the local peak of the eclipse.
 
A total {{w|solar eclipse}} occurred in North America {{w|Solar eclipse of April 8, 2024|on April 8, 2024}}, a week after this comic. A solar eclipse occurs when the Moon moves between the Sun and the Earth, but in order for it to be a total eclipse, the Sun, Moon and the observer's position on the Earth need to line up nearly exactly, and at the right distances (if the Moon is too far away, the eclipse will be annular, rather than total). When such a phenomenon occurs, there's a "path of totality", referring to the range of locations where such an alignment occurs (though only for a few minutes in each location). Away from, but near to, the path of totality (and outside of the specific time of totality), the Moon partially obscures the Sun. In Boston, where [[Randall]] lives, the Sun will be 93% obscured at the local peak of the eclipse.
  
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The comic refers to the fact that the human eye is very good at adapting to different levels of light intensity. At 95% occlusion, it's noticeably dimmer outside, but the effect is similar to light in late evening, or on a heavily overcast day, nothing particularly remarkable. Using eclipse glasses (or a simple pinhole camera), it's possible to see the Sun being occluded, but someone unaware that an eclipse was occurring would barely notice that anything was happening.  
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The comic refers to the fact that the human eye is very good at adapting to different levels of light intensity. You can see this effect when you go into your house after being in outside in the Sun. The house looks dark for a moment, but after a while the light level feels comfortable again. A well lit room is only 1600 lumens, compared to the Sun which has a brightness of 120,000+ lumens, a 75 fold difference. Therefore, you would think that a 95% eclipse would result in things looking only 5% as bright as normal, but because our irises adjust to diminishing available light, it will still seem light out even at the maximum point of coverage. The dimming light is similar to light in late evening, or on a heavily overcast day, nothing particularly remarkable. Using eclipse glasses (or a simple pinhole camera), it's possible to see the Sun being occluded, but someone unaware that an eclipse was occurring would barely notice that anything was happening.  
  
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Within the path of totality, it's a different situation. Though an eclipse for any given locale could be experienced at all times from dawn to dusk, the most dramatic ones will occur somewhere around the middle of the observer's day. When the Moon fully obscures the Sun, for a brief period of time, the area becomes almost fully dark without the usual or expected {{wiktionary|crepuscular}} transition. Temperatures drop noticeably in a matter of minutes and wildlife (and people) may react in [https://www.nytimes.com/2024/04/04/us/solar-eclipse-animals-pets-zoo.html unusual ways]. The level of light in the rest of the sky is similar to that which accompanies a sunset, but in all directions and without the horizon's red light effect. Most dramatically, the previously unseeable Sun's upper atmosphere can be viewed, as a ring around the dark circle of the Moon, with the naked eye (which should ''only'' be possible once the bright solar disc is obscured, and until it starts to appear again). At the very limits of totality, though perhaps most dramatic at its ending, the smallest sections of the bright solar surface will briefly be the only parts to shine through low points on the Moon's edge to form {{w|Baily's beads}}, or a "diamond ring" effect, not at all visible beyond the narrow central strip of the eclipse.
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Within the path of totality, it's a different situation. Though an eclipse for any given locale could be experienced at all times from dawn to dusk, the most effective ones will occur somewhere around the middle of the observer's day. When the Moon fully obscures the Sun, for a brief period of time, the area becomes almost fully dark without the usual or expected {{wiktionary|crepuscular}} transition. Temperatures drop noticeably in a matter of minutes and wildlife (and people) may react in [https://www.nytimes.com/2024/04/04/us/solar-eclipse-animals-pets-zoo.html unusual ways]. The level of light in the rest of the sky is similar to that which accompanies a sunset, but in all directions and without the horizon's red light effect. Most dramatically, the previously unseeable Sun's upper atmosphere can be viewed, as a ring around the dark circle of the Moon, with the naked eye (which should ''only'' be possible once the bright solar disc is obscured, and until it starts to appear again). At the very limits of totality, though perhaps most dramatic at its ending, the smallest sections of the bright solar surface will briefly be the only parts to shine through low points on the Moon's edge to form {{w|Baily's beads}}, or a "diamond ring" effect, not at all visible beyond the narrow central strip of the eclipse.
  
 
The graph in this strip points out that the difference between 91% (or even a 99%) eclipse and a total eclipse is dramatic. An almost total eclipse is barely noticeable, while a total eclipse is a visual phenomenon unlike any other. This is a situation where being close to the path of totality and being on it makes a huge difference.  
 
The graph in this strip points out that the difference between 91% (or even a 99%) eclipse and a total eclipse is dramatic. An almost total eclipse is barely noticeable, while a total eclipse is a visual phenomenon unlike any other. This is a situation where being close to the path of totality and being on it makes a huge difference.  

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