Event Date: June 20th
Time: 4:09 PM
Brief
It is officially summer at the time above for the northern hemisphere. In relation to the Sun's path, our star crosses 90º in ecliptic latitude just 2 seconds earlier, from our point of view. Since the southern hemisphere starts its winter season, it is most appropriate to call this the June solstice. I defined all the terms for celestial and ecliptic guidelines back on the March equinox. Saving at least an hour of repeating all of that, you can refer back to that at the link above. Below are two images of the Sun alone a yellow line; green on top of red, using light-color combination. For both, I enhanced the boldness of the gridlines so that they could be seen more easily against the daytime sky.
Time: 4:09 PM
Brief
It is officially summer at the time above for the northern hemisphere. In relation to the Sun's path, our star crosses 90º in ecliptic latitude just 2 seconds earlier, from our point of view. Since the southern hemisphere starts its winter season, it is most appropriate to call this the June solstice. I defined all the terms for celestial and ecliptic guidelines back on the March equinox. Saving at least an hour of repeating all of that, you can refer back to that at the link above. Below are two images of the Sun alone a yellow line; green on top of red, using light-color combination. For both, I enhanced the boldness of the gridlines so that they could be seen more easily against the daytime sky.
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| click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp. |
Detailed
Just as a reminder, which I mentioned the the March equinox journal, the solstice does not happen at 6 (h)ours of right ascension, although the timing is close to that for when the Sun reaches 90º in ecliptic longitude. It reaches the 6h mark this year about 7 minutes earlier, just after 4:02 sharp. As a result of precession of the Earth's axis, there are very rare times for which a solstice may occur for both within a minute or even seconds of each other. If I find that to happen sometime over the years if I continue this blog long enough, I will for sure mention it!
As a final note for the second image above, it is a little easier to see how the 90º line goes directly through the Sun's disc, seemingly splitting it in half. I set the clock back two seconds to 4:08(.58) which as mentioned in the brief, is when this happens.
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