Satellites and More – 2020 #2

Edmund Weiss (1837-1917) and many astronomers since have called asteroids “vermin of the sky”, but on October 4, 1957 another “species” of sky vermin made its debut: artificial satellites.  In the process of video recording stars for possible asteroid occultations, I frequently see satellites passing through my 17 × 11 arcminute field of view.

I’ve put together a video montage of satellites I serendipitously recorded during the second half of 2020.  Many of the satellites move across the field as “dashes” because of the longer integration times I need to use for some of my asteroid occultation work. A table of these events is shown below the video. The range is the distance between observer and satellite at the time of observation. North is up and east is to the left.

North is up and east is to the left; field size 17′ x 11′

Interestingly, two of the satellites above (7 & 22) are in retrograde orbits, that is their orbital inclination is > 90˚ and their east-west component of motion is towards the west instead of the east. However, one of the prograde-orbiting satellites (11) appears to be orbiting retrograde. It has an orbital inclination close to 90˚ (87.5˚), and must appear retrograde because of the vector sum of the line-of-sight motion of the satellite plus the Earth’s rotation, but I have not yet found an expert who can confirm this.

Satellite #12 has an interesting story. It is piece of debris from the Iridium 33 satellite after the 10 Feb 2009 collision between Iridium 33 and Cosmos 2251. A cautionary tale as now thousands of internet satellites are being launched into orbit.

Because of the long integration time, satellite #14 was only captured on a single frame, but the satellite trail clearly shows this piece of Fregat debris is tumbling and leading to rapid and no doubt periodic changes in brightness.

The satellite trail of #17 looks funky because wind was shaking the telescope as the satellite crossed the field.

There were four satellites I was unable to identify, shown in the video below. They are either classified satellites or, more likely, small pieces of space debris that only government agencies are keeping track of. Interestingly, three of the four unidentifiable satellites were moving in retrograde (westward) orbits.

Unidentifiable satellites

I recorded a non-operational geostationary satellite, Intelsat 5, now in a “graveyard” orbit, on 30 Aug 2020.

Intelsat 5

On 29 Nov 2020, I recorded a rapidly tumbling Briz-M rocket body. Below the video you’ll find the light curve showing the large amplitude of its reflected light variation.

Briz-M rocket body, rapidly tumbling
Briz-M rocket body, high-amplitude light curve

The NOAA-13 environmental satellite failed shortly after launch, and as you can see from the light curve below the video, it got dimmer as it crossed the field—probably indicating that this retrograde, non-operational satellite is slowly tumbling.

NOAA-13, in a retrograde orbit
NOAA-13 dimmed as it crossed the field

Occasionally, I record other phenomena of interest. Meteors during this period are described here, and you will find a couple of jet contrails in the video below.

Hughes, D. W. & Marsden, B. G. 2007, J. Astron. Hist. Heritage, 10, 21

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