Tag: Long March

Edmund Weiss (1837-1917) and many astronomers since have called asteroids “vermin of the sky”, but since October 4, 1957 another “species” of sky vermin made their debut: artificial satellites.  In the process of video recording stars for possible asteroid occultations, I frequently see satellites passing through my ~¼° field of view.

I’ve put together a video montage of satellites I’ve recorded between June 21, 2017 and October 20, 2017.  The component events are presented chronologically as follows:

You’ll notice that sometimes the satellite crosses the field as a moving “dash”.  That’s because sometimes I used longer exposure times to record a fainter target star.

In general, the slower the satellite is moving across the field, the higher is its orbit around the Earth.  One must also consider how much of the satellite’s orbital motion is along your line of sight to the satellite.  In the following video clip, you’ll see a slow-moving “tumbler” satellite moving from right to left across the top of the field.

On January 10th of this year, I figured out how to identify satellites crossing the telescope field of view using the amazing program Guide 9.1, which I use for all my observatory research work.  On March 4th, I was hoping to be the first to record the asteroid 3706 Sinnott passing in front of a star.  This asteroid is named after Sky & Telescope Senior Editor Roger Sinnott, whom I had the good fortune to work with in writing the article “A Roll-Down-Roof Observatory” in the May 1993 issue of Sky & Telescope, p. 90.  Roger is amazing.  He took an article that I had written and edited it in a way that only lightly touched my original text yet ended up saying what I wanted to say even better than I was able to say it myself.  The mark of a great editor!  Anyway, I’m sure Roger remembers me and I was looking forward to giving him the news that I had observed the first stellar occultation by “his” asteroid.  Alas, it was not to be, because, as so often happens, the too-faint-to-be-seen asteroid passed either above or below the target star.  The consolation prize, however, was recording a third stage Long March Chinese rocket booster (CZ-3B R/B; NORAD 43004U; International # 17069D) passing through the field.  This rocket launched on November 5, 2017, and added two satellites to China’s Beidou positioning network.  As you can see in the light curve below, the rotation period of the rocket booster is a bit longer than the 19 seconds of usable video I had.

Once in a great while, I record a telescopic meteor.  Here are two.

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