Latest Comic : Friday, April 16. 2021

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Seeing a spacecraft docking with ISS from Earth

Crew Dragon approaches Int'l Space Station on April 5, 2021

With clear skies yesterday evening, it was a perfect time to watch the International Space Station make a pass near zenith. Like last month, I set my P1000 camera to video mode while I tracked manually. When I reviewed the recording, I was happy to see that the frames were mostly in focus. The quality was actually one of the best I got with the camera, with most of the modules easily distinguishable. But then I noticed a faint dot next to the station in much of the frames, so I looked up the news.

It turned out that the SpaceX Crew Dragon spacecraft was moving from one docking port to another during those moments. The move only took 39 minutes from undocking (19:31:02) to soft capture (20:10:12), so it was out of sheer coincidence and luck that I was recording while spacecraft was near, but not docked to the space station. The fact that the Crew Dragon's was just big enough to show up in the frames helped, too. The 109-meter ISS was 83 pixels wide at the closest approach, so the Dragon being 4 meters in diameter appeared as a 3-pixel dot. In any case, I was pleasantly surprised to find out that I photographed this occasion. It was something I had on my bucket list.

Device: Nikon P1000
Settings: 3000mm - ISO 200 - 1/1000s - f/8
Filters: None
Time: 2021-04-05 20:05:26-20:06:12 KST
Location: Naju, Korea
432 video frames processed with PIPP 2.5.9, RegiStax 6.1.0.8, and Pixelmator Pro 2.0
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ISS brushing past afternoon Moon

Illuminated ISS passes in front of the first quarter Moon on March 22, 2021 (50% - click for full size)

While the Sun is up in the sky, the Moon is still visible at the right phases due to its brightness. Although the Int'l Space Station can also become bright, it's only visible shortly before to about an hour after sunset. So when I found out that it was to pass in front of the Moon while the sky was fairly bright (36 minutes before sunset), I wasn't sure of the results. Would it look brighter or darker than the Moon? Would it even be visible when it's not in front of the Moon?

These questions were cleared up when I got the Moon at that moment on video. Because of the uncertainties and the quickness of the pass, I used 4k 30fps recording instead of the usual 7-frame burst mode on the P1000 camera. The prediction calculation was slightly off and the ISS was not centered, but I still managed to get more than 10 useful frames. The fuzziness is due to video compression, but it's far better than nothing. Interestingly enough, the radiators on the space station were quite a bit brighter than the surface of the Moon in general.

Shots of ISS caught on the video and the resulting stacked image

When we take a closer look, the prominent features of the ISS are easily discernible. The solar panels are stretching from top to bottom, while the Russian modules Zvezda (right) and Zarya (center) are more illuminated than the multi-national modules on the left. Considering this success, it looks like I should try the video recording again for the next ISS pass.

Device: Nikon P1000
Settings: 3000mm - ISO 400 - 1/1000s - f/8
Filters: None
Time: 2021-03-22 18:10:36 KST
Location: Buan, Korea
12 video frames processed with Pixelmator Pro 2.0
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Appearance on tvN "You Quiz on the Block" episode #96

Commemorative photo with Yoo Jae-suk (left) and Jo Se-ho (right)

Thanks to an SBS show last year, I was invited to appear on the popular cable television program "You Quiz", and that episode aired yesterday. I liked the way it turned out, and it seems that a lot of people enjoyed it as well, especially the parts involving my wife.

Video

- Highlights (YouTube/tvN), #2, #3, #4
- Episode Digest (YouTube/tvN)
- Highlights (YouTube/unofficial)
- Preview (YouTube/tvN)
- Highlights (tvN), #2, #3, #4
- Highlights (Naver), #2, #3

Articles
Episode Review
- Herald POP
- OSEN

About Me
- Maeil Business
- Newsen
- Gukje News
- BizEnter
- Ilyo News
- Single List
- News Inside
- Top Star News

Episode Preview
- The Korea Times
- Top Star News

Extreme temperature swing leads to EV range swings

705.5 km driven using 114.3 kWh at an average of -6C (21F)

There have been some wild changes in outside temperature during the past week. On Wednesday, February 17, it dropped to as low as about -10C (14F) and stayed consistently low. In contrast, it went up as high as 21C (70F) on Sunday, February 21. It just so happened that I needed to drive my Bolt EV from Naju to Seoul and back on those days. I did anticipate a big difference in drivable range between them, but it was still a bit jarring to experience it firsthand in such a short period.

The trips were made mostly on the same corridor of Honam / Cheonan-Nonsan / Gyeongbu expressways, which took up about 80% of the total distance and where I drove at a speed of 100 km/h (62 mph) on the dashboard. On other roads, the speed limits were always observed. I did not use any heating or air conditioning at all, as evidenced by the pie chart on the screen showing that all the energy was spent for driving.

A Naju-Seoul trip, which is roughly 320 km (200 miles) one way, can be made without a pit stop if the temperatures are above freezing. On Wednesday, I saw the drivable range drop considerably shortly after starting out. Although the battery was initially nearly full, I needed to stop and recharge mid-way, just enough so that I wouldn't be late for the schedule. The temperatures stayed between -8C and -5C (18F and 23F).

The return trip was the same - I filled up the car before starting, but had to recharge at the last service area to give myself a bit of safety margin. In the end 114.3 kWh was spent during the total trip distance of 705.5 km (438.4 miles), resulting in an efficiency of 6.17 km/kWh (3.84 mi/kWh). Given that I only try to spend a maximum of about 50 kWh on a single charge, you can see why I had to do the pit stops.
706.5 km driven using 85.1 kWh at an average of 17C (63F)

The situation on Sunday was completely different. It was exceptionally warm for Winter and I could foresee that I would reach Seoul quite comfortably on a single charge. Indeed, the temperature stayed around 20C (68F) for most of the trip until the Sun set. The dashboard showed about 100 km (62 miles) of range left when I reached the hotel.

The next day wasn't much different, although slightly cooler. I was returning to Naju with a full charge while the outside temperature was mostly in the 15C to 20C range (59F to 68F). Total distance of 706.5 km (439.0 miles) was covered using just 85.1 kWh, which gives an efficiency of 8.30 km/kWh (5.16 mi/kWh).

To put this into perspective, the efficiency was reduced by 25.7% just because the temperatures dropped by 23C (42F) and all other things remained more or less the same. Had I used heating, things would have been worse. This highlights how sensitive the electric vehicles are to outside conditions.
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Jupiter-Saturn Conjunction of 2020

Jupiter, Saturn, their major satellites, and star HIP 99314 are seen together on December 21, 2020 (click for full size)

Jupiter and Saturn appeared closest to each other in nearly 400 years on the Winter Solstice of 2020. For this Great Conjunction, the two planets were only about 6 arc seconds apart, which meant that I was easily able to take a photo of both in a single frame as you can see here. Some had expected that they might appear as a single dot, but it turned out that Saturn was discernible as a fainter "bump" on the top right side of Jupiter to the naked eyes.

To show the planets and the satellites together, I used varied exposures and then combined the results into a single photo. Titan was the dimmest that I could photograph, and it appears very faintly to the right of Saturn. Interestingly, a star named HIP 99314 was also caught in action between Io and Europa, which means that this conjunction was actually a triple affair.

Nikon P1000 taking photos of the conjunction

By the way, I was worried that I wouldn't be able to see the phenomenon in person because it was pretty cloudy throughout the day. Luckily, most of them went away as the Sun set and I was able to take the photos for about an hour until the low-hanging clouds started to block the view. The next closest conjunction happens 60 years later and I'm not sure if I'd be around to see that, so I was glad that the weather decided to cooperate in the last minute.

Device: Nikon P1000
Settings: 3000mm - f/8
- Jupiter: 24 photos, ISO 200, 1/30s
- Saturn: 13 photos, ISO 400, 1/30s
- Satellites: 17 photos, ISO 800, 1/5s
Filters: None
Time: 2020-12-21 18:20-18:40 KST
Location: Naju, Korea
Photos processed with PIPP 2.5.9, RegiStax 6.1.0.8 and Pixelmator Pro 2.0

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