Entries tagged as planet

100-minute tracking of Jupiter

Jupiter and the Galilean moons seen on 00:44, April 20, 2018

Jupiter and its four major satellites (Galilean moons) are good targets for time lapse photography because of the relatively rapid movement. The rotational period of the planet is slightly less than 10 hours, and Io, the innermost of the Galilean moons, orbits the planet in about 42.5 hours. Under good conditions, these things become noticeable over a span of just about an hour.

Shortly after midnight of April 20, 2018, Io came out from behind Jupiter on the left side, while the Great Red Spot was moving towards the back of the planet on the right side after being in the center. These were all captured on my camera as I took 597 photos of the Jovian system over a period of 100 minutes between midnight and 01:40AM. The photos were then stacked and processed in 1-minute intervals (6 photos on average), like the one you see above, then put together into video as you see below.


I think it shows the dynamics of these celestial objects quite well. Now that I have a good grasp of the workflow for making a planetary animation, I should be able to make a similar one for Mars when it approaches Earth close enough to be seen as half the apparent size of Jupiter next July. Before wrapping up, here's a bonus picture of the Jovian system that I took just after photographing the Sombrero Galaxy. You can actually see Io casting a tiny shadow on Jupiter. I thought I would never see that sort of thing on my telescope.

Jupiter and the Galilean moons seen on 01:03, April 19, 2018

Telescope: Celestron NexStar 6SE
Device: Sony A5000 (prime focus)
Settings: (1500mm) - ISO 100 - 1/15s(#1), 1/20s(#2) - (f/10)
Filters: Baader Moon & Skyglow
Time: 2018-04-20 00:00 ~ 01:40(#1), 2018-04-19 01:03(#2) KST
Location: Naju, Korea
597(#1), 6(#2) photos processed with PIPP 2.5.6 and RegiStax 6.1.0.8

Getting the telescope back on its feet

Jupiter and Saturn on April 8, 2018

It's been about two years since I did astrophotography with my Celestron telescope. When I finally took it out of storage to take the photos of ISS recently, I noticed that the shots weren't as clear as I expected. The same problem came up as I tried to take photos of the Orion Nebula yesterday, and I realized that the collimation of the telescope was significantly off. After about an hour of fiddling, the problem was fixed and I was able to see the bands of Jupiter and the Cassini Division on Saturn again. It looks like I'm good to go for the next few months of observation, including the closest approach of Mars on July 31. Here are the photos of the two planets in the order of original (from 4K 60fps recording), stacked, and wavelet processed results. Resolution was roughly 0.32"/pixel due to the iPhone X having slightly wider lens than iPhone 6S Plus.

The look of Jupiter before and after collimating the telescope


Telescope: Celestron NexStar 6SE + X-Cel LX 9mm eyepiece
Device: iPhone X (afocal)
Settings: 28mm - ISO 50 (Jupiter) / 250 (Saturn) - 1/60s - f/1.8
Filters: None
Date/Time: 2018-04-08 05:18 (Jupiter) / 05:30 (Saturn) KST
Location: Naju, Korea
100 (Jupiter) / 46 (Saturn) photos stacked with PIPP 2.5.6 and RegiStax 6.1.0.8

Moon-Mars-Venus conjunction of 2017

Moon, Mars, and Venus line up in the western sky

As I dropped by Gwangju to catch a movie (I'll be posting a comic tomorrow), the western sky was adorned with an alignment of some of the bright bodies of the solar system as seen from the Earth - the Moon, Mars, and Venus. The occurrence was relatively well-publicized, but I forgot to carry a dedicated camera tonight. Luckily, the telephoto lens of the iPhone 7 Plus pulled through and I was able to capture this sight over the neighbourhood just before Venus dropped behind the buildings.

Device: iPhone 7 Plus
Settings: 56mm - ISO 1000 - 1/12s - f/2.8
Filters: None
Time: 2017-02-01 21:12 KST
Location: Gwangju, Korea
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Looking out the window to see the Milky Way

The Milky Way Galaxy adorns the southern sky, atop the apartments (13.5% size)

A few hours after walking in the rain to see a movie yesterday, I was getting ready to sleep. Then I noticed that the sky was crystal clear, something I haven't seen in more than nearly two weeks (or three, in the night). Not to pass up this opportunity, I got my camera out. With so many stars visible, I wondered if the Milky Way Galaxy could be captured even with all the lights from the apartment buildings nearby.

After a few tries, it became clear that indeed it could be done, if somewhat faintly. Adjusting the levels, curves, and contrast brought out further details. Individual colour channels were untouched, yet the sky showed a very nice gradient. This may be an unintended affect of the light pollution near the horizon and I like how it turned out.

Device: Sony A5000 + SELP1650 (E PZ 16–50 mm F3.5–5.6 OSS)
Settings: 16mm - ISO 2000 - 20s - f/3.5
Filters: None
Time: 2016-07-08 00:44 KST
Location: Naju, Korea
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Saturn and its satellites

Rhea - Tethys - Saturn - Dione - Titan on June 15, 2016

I used the Opteka 2x teleconverter lens for astrophotography for the first time when I took another series of photos of the planets two days ago. This is supposed to be used with telephoto mirror lenses, but that's basically what my telescope is as well and I hoped it would be usable here. Test shots during the day came out alright, maintaining better contrast than the 2.5x Barlow lens I had been using. As you can see here, it performs reasonably well in the night, too.

I didn't originally intend to photograph the Saturnian satellites because they are quite dimmer than the Jovian ones. The four biggest Jovian satellites have apparent brightness in the magnitude 5 range, while the biggest and brightest Saturnian satellite, Titan, is around magnitude 8. The three largest after Titan are of magnitude 10. That's why I didn't take separate photos with longer exposure. Even so, post-processing the background area revealed the dim satellites. I noted their relative positions with the caption. Dione may be barely visible on on well-tuned screens.

Telescope: Celestron NexStar 6SE + Opteka 2x Teleconverter
Device: Sony A5000 (prime focus)
Settings: (3000mm) - ISO 100 - 1/3s - (f/10)
Filters: None
Time: 2016-06-15 00:12-00:13 KST
Location: Naju, Korea
26 photos stacked with PIPP 2.5.6 and RegiStax 6.1.0.8

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