The CASTOR Satellite Catalogue began 10 years ago with a quest to optically detect 1,957 individual satellites using nothing more than a small-aperture telescope and a single CCD camera. Over the 2007 year, this equipment successfully detected over 2,050 satellites in order to celebrate the 50th anniversary of the launch of Sputnik 1: the Earth's first artificial satellite.

   Now, 60 years since Sputnik, the CASTOR Satellite Catalogue has been completed. This has been a monumental achievement in the realms of amateur astronomy and professional space surveillance alike. For the first time, a single individual has optically detected nearly one fifth of all catalogued satellites. This was done for several reasons.

   The first, and primary, reason was to answer the question of how many satellites could be detected with commercial off the shelf telescopes and CCD cameras from a single location on the Earth's surface. The answer is approximately 4,300 satellites. This number was determined using mainly optical, but also amateur radio equipment.

   The second reason this was done was to demonstrate to the public in all nations that the large number of satellites in orbit is actually a reality and not just a news story. A two hour observing session with a 11.5 degree field of view could net an average of 40 satellites in only a two hour time span. This represents the satellites that could be detected with the CCD camera. With each observing session, there were additional satellites that could not be optically detected (cubesats and small debris). The CASTOR Satellite Catalogue successfully verified the large satellite population density.

   The third reason was of course to advertise CASTOR's expertise in space surveillance. This science has very few real representatives who can competently propagate an orbit element set or appreciate a satellite's optical signature. These and other skills take a large amount of time in the field to acquire. No amount of administrative or managerial experience can make up for that.

   Since January 1, 2007, there have been a number of events that have greatly increased the overall satellite population, including the intentional Fengyun-1C destruction and of course the Iridium-Cosmos collision (of which CASTOR detected several pieces). These events have nearly doubled the catalogued satellite population, further increasing the probability of satellite collision.

   The final images of the CASTOR Satellite Catalogue were obtained on January 1, 2017 (with exactly the same equipment), exactly 10 years after the monumental survey began. There has been so much that has been learned about the satellite population from this survey alone that it has broadened experience and knowledge to heights never before imagined. This achievement is considered to be one of my finest; however, there are other challenges that are presenting themselves. The award of my PhD is fast approaching and the furthering of my space science career is now a priority.

   To those who are thinking about beginning their journey in space science or space surveillance: It is not enough to simply follow those who have come before you. You must explore as much as you can while you have the ability to do so. Failing to do that will render your career an empty one without any sense of accomplishment. With my outreach, through star parties, courses and this web site, I have shared my own unique space science journeys as much as I could. Hopefully, someone else will pick up the baton and continue where I left off. I am hopeful that someone will be able to detect a greater amount of satellites and discover new wonders that I can only dream of right now.

   The CASTOR Satellite Catalogue began by wondering how best to celebrate the 50th anniversary of a monumental technological achievement in 1957. It concluded with a shocking and amazing discovery about our satellite population. When my PhD is awarded, I will fondly remember those nights in which I observed our orbiting friends; active or inactive, domestic and foreign, young and old. However, I will also wonder what discoveries still await me, and others.





The End of an Era: The Conclusion of the CASTOR Satellite Catalogue Was Last Modified On February 14, 2017