Starlink Satellites, 04 January -
12 March 2020
Second Launch Observed on 04 January 2020
The second set of 60 Starlink broadband satellites, launched on 11 November 2019, was well-placed to see in early January 2020. The night of 04 January was clear with a first quarter Moon, but not particularly transparent. The main group of satellites passed virtually overhead. I was able to record 41 of them, including three slightly out-of-plane with the main group, along with several other satellites that happened to pass through the field-of-view (and two aircraft).
The Starlink satellites pass from 2 o'clock to 8 o'clock in the below animation. Most were invisible to the naked eye in the moonlit sky, but two were very very prominent, with brightness similar to the stars in Cassiopeia.
Fourth Launch Observed on 12 and 19 February 2020
By mid-February 2020, the satellites from the fourth Starlink launch on 29 January 2020 had rotated into visibility in the mornings. The morning of 12 February, although very cold, presented an opportunity to image the objects. The satellites came out of the Earth's shadow at an altitude of about 20°, close to the Moon. The main group consisted of 31 satellites, all in a line with a typical spacing of about 12 seconds. It was possible to see at least 10 satellites at the same time - the sight of 10 "stars", all moving as one relative to the stellar background, was quite surreal! Towards the end of the pass, one of the satellites was moving visibly faster than the others and overtook another. Currently, most of the satellites are in a circular orbit at an altitude of about 340 km, orbiting the Earth 15.75 times a day, climbing up towards an operational altitude of 500-550 km. Starlink-1179 is in a lower orbit of 279 by 291 km, circling the Earth 15.95 times a day, so appearing to travel 1.3% faster.
I attempted to video the passage of the starlink satellites through the border of Corona Borealis - Serpens. Equipment used: Sony A7S camera, driven, 100 mm telephoto lens f/2, ISO 16,000. Some acceleration of the event was needed to reduce the size of the video file. The satellites are nominally in the same orbit, but our perspective from the rotating Earth gives the impression that they sweep through a band of the sky. The impact of all these satellites, flashing through the fields-of-view of the telescopes around the word, as shown in the image, remains to be seen.
On the morning of 19 February it was again clear and I took the opportunity to record the passage virtually overhead of the Starlink3 constellation. I used a fish-eye lens to record the passage. Although the satellites are launched in groups of 60 into a low earth orbit, they start to spread out as they propel themselves into their working orbit at an altitude of 550 km. On 19 February, the main group contained 28 satellites that passed in about 8 minutes. The movie below captures most of the satellites from approximately 05:40:30 to 05:49:50 UT. The still frame, taken at 05:47:11 UT shows 14 satellites. Equipment used: Canon 60Da camera, 8 mm fish-eye lens f/4, ISO 3200, 2 s exposures.
Fifth Launch Observed on 12 March 2020
The morning of 12 March was not very clear, the Moon was up and it was very, very windy, but it was the first opportunity to record the latest constellation of Starlink satellites (Starlink 4) from the 5th launch on 17 February. The main pack (about 44 satellites out of 60) passed by in an 18-minute window. They were usually 25-27 seconds apart, so not close as when other constellations have been seen, but it was still possible to see six or more at once. All bar one object could be identified using the prediction from heavens-above.com: the exceptional object moved like all the others but there was no prediction for it. All the satellites passed close to the star Pherkad (γ Ursae Minoris, magnitude 3.05) which most of them matched in brightness.
I now normally use a driven mount when recording Starlink satellites, but I forgot to switch it on straight away! As a result, the stacked composite has the stars rotating about a fixed point.