Entries tagged as star

Today’s “The Toon-Box”

Defined tags for this entry: , ,

First sunrise of 2024 from Bitgaram City

Sun rises over Naju Bitgaram City on January 1, 2024

2023 had been another interesting year. In terms of travelling around the world, things have gotten almost back to the levels of pre-pandemic levels. This allowed me to visit many new places as well as revisit some old ones. But for watching the first sunrise of the year, nothing is more comfortable than doing it right at home. Thankfully, skies were almost totally clear, allowing my phone to capture the scene with clarity. Like the photo, I hope everyone has a bright year ahead of you.

For the full 12-minute progress (sped up 4 times) of the sunrise, check out the video that I uploaded.

Device: iPhone 15 Pro
Settings: 77mm equiv. - ISO 25 - 1/469s - f/2.8
Time: 2024-01-01 08:00 KST
Location: Naju, Korea
Defined tags for this entry: , , , , , ,

Today’s “The Toon-Box”

Defined tags for this entry: , , , , ,

Near-simultaneous solar transit of ISS & Tiangong

The two biggest objects orbiting the low earth orbit, International Space Station (ISS) and the Tiangong Space Station (a.k.a. Chinese Space Station or CSS) can be seen transiting the Sun every now and then. But because their orbital characteristics are different, it's hard to see the two like that on the same day within the 200 km range. And it's much rarer for the two to be seen in front of the Sun at the same time. But earlier this month, I found out that I could see the next best thing - seeing the two make the transit from the same location within 14 minutes of each other.
Composite of ISS and Tiangong passing in front of the Sun on 11 AM, April 7, 2023
The result of this observation is shown here as a multiple-frame composite. Thanks to the weather, both space stations were photographed clearly and you can make out their distinct shapes - the less dense one is Tiangong. And because the observations occurred within a short timeframe, it's easy to gauge the relative apparent size difference between each other.
Comparison of the ISS and Tiangong's apparent size
Close-ups of the two space stations make this more apparent. The ISS was 53 arc-seconds wide at 521 km away, while Tiangong was 37 arc-seconds wide at 460 km away. The difference in distance shows that Tiangong's orbit is lower than that of ISS. In fact, Tiangong's nominal orbit is around 375 km, while ISS is at about 420 km.

If the ISS was observed at the same distance, it would have been 60 arc-seconds wide. This means that Tiangong, which was fully built a few months ago, is roughly 60% as wide as the ISS and much bigger than what the transit finder website claims. I think that it's showing the size of just the core module (Tianhe), not the entire structure.

Maybe if I get lucky I will be able to spot the two making the transit at the same time in the future. Until then, I'll keep looking.

Device: Nikon P1000
Settings: 3000mm - ISO 200 - 1/1000s - f/8
Filters: ICE N100000 (Neutral Density 16.5 Stop)
Time: 2023-04-07 11:00 - 11:14 KST
Location: Dangjin, Korea
28 photos (14 each) processed with Pixelmator 3.3.2, RegiStax 6.1.0.8, and PIPP 2.5.9

Today’s “The Toon-Box”

Defined tags for this entry: , , ,

Copyright (C) 1996-2024 Woo-Duk Chung (Wesley Woo-Duk Hwang-Chung). All rights reserved.