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Meiying Lee
Sydney, Australia
07/29/2023
05:30 pm

Equipment Details:

Canon R7 + SIGMA 60-600mm F4.5-6.3 S DG OS HSM Sports

Post-processing Details:

Using Startrails to stack consecutive shots of Venus into a setting trail, with 5 minutes between each Venus photo. The photo of Taipei on the left was taken from 5:54:28 pm to 6:00:13 pm on July 24th, with a total trajectory of about 6 minutes. The photo of Sydney on the right was taken from 5:24:29 pm to 5:30:14 pm on July 29, with a total trajectory of about 7 minutes.

Image Details:

Crescent Venus Setting Trail
These two images show the difference in the western setting trail of Venus in the northern and southern hemispheres. The one on the left was taken in Taipei at 25.0°N at around 6 pm on July 24, and the one on the right was taken in Sydney at 33.9°S at around 5:30 pm on July 29. That's right, I really came to Sydney! This comparison photo reveals some interesting facts:
1. The difference between the northern and southern hemispheres can be seen from the westward trajectory of Venus, and the latitude of the shooting location can also be judged. Stars fall to the right (north) and down (west) in the northern hemisphere, while stars fall to the left (south) and down (west) in the southern hemisphere. And because of the difference in latitude, the degree of inclination of the two trajectories is also different. Taipei's track is steeper than Sydney's, indicating that Taipei's latitude is relatively low.
2. Venus is only about 10% illuminated recently, so the phase is crescent-shaped. Therefore, the position of the sun can also be judged from the direction of the crescent. The direction of the crescent in the northern hemisphere is lower right, indicating that the sun is northwest of Venus. In the southern hemisphere, the sun is to the southwest of Venus.
3. The color of the sky in the two photos also has an important meaning. It is summer in the northern hemisphere, and the shooting time is 6:00 pm, which is about 40 minutes before sunset in Taipei, so the sky is still very bright blue. However, it is winter in the southern hemisphere, and the shooting time is 5:30 pm, 20 minutes after sunset in Sydney, because at this time, the sky with Venus sinking in the west is already a slightly darker orange after sunset.