There are several projects I have - one of them is comparing the various available satellite catalogs. The "default" official international satellite catalog is provided by the US Air Force - the 18th Space Control Squadron (was the Joint Space Operations Center (JSpOC) catalog). The Air Force provides a catalog that is adequate at best and appears to be a candidate to move. I am hoping to contribute to the conversation about where that satellite catalog should end up. At one time I was an Orbital Analyst and helped maintain that list, I remember cataloging many satellites myself.

Another major catalog is the International Scientific Optical Network (ISON) which is maintained on a web page based in Russia.

One thing that should concern us is that the "official" satellite catalog does not release orbital elements for a number of satellites that have classified and even unclassified missions. To give them cover, they also do not release elements for their upper stages, sub-satellites deployed on those launches, etc. This classification appears to cause some important situations to escape the normal review. For instance there are satellites in Sun Synchronous orbits and many have broken up, scattering pieces into a heavily used orbital regime.

Recently the US has started to release orbital parameters on many of these but that is a story - I will update this page when I can.

This article Errors In The Default Official Satellite Catalog has more details.

And there are also "deep space" objects in "Molniya" orbits that have broken up - see a mention below.

I am told that some of the orbits' classification is only "For Official Use Only" but that still greatly complicates the distribution of those orbital descriptions. Maybe in part due to that, some DoD satellites (with both FOUO and with unclassified orbits) have broken up but are not listed in the NASA list of breakups. NASA has an Orbital Debris Program Office and they publish a list of satellites that have broken up - but some of the breakups are not listed.

Here is the latest version of that list of breakups: The NASA History Of On-Orbit Fragmentations

There is now a new version of that, as of 2019, and I will correct my link as soon as possible.

My interest is to calling attention to those that have been missed. The U.S. government puts out a bulletin that lists objects that are considered orbital debris, and there is some discussion of what caused this debris. Many satellites have broken up and created clouds of orbital debris, and many of these are listed as "breakups" in the official report. But a number of objects have broken up or shed pieces but have not made that report. Some of the objects that have apparently broken up or shed pieces, but do not appear in the official list, are:

The latest version of the official list was in 2008 (now 2019), but they have published updates recently that listed the NOAA polar satellites. That report is far overdue for an update; perhaps they will update us on the DMSP satellites at some time. I will add some more detail to these projects as I can.

Satellites That Have Reentered But Are Shown In The Active Satellite Catalog

If you look at the "Low Perigees" page it has a table of satellites that we know have reentered - but are not shown that way in the 18th Space Control Squadron's satellite catalog. Satellites such as 20167, 32707, and 35939.

Inconsistency - This Probably Should Not Bother Us But Still It Does

There are so many examples, where to start? The DMSP satellites had TLEs that were (inconsistently) not released. The most of the orbits are now released but for a long time the catalog had some odd inclusions. For instance satellite 9415 - DMSP F1, of the 5D-x series. This is the first of the 5D-x series and so is a 5D-1. The TLEs for it a shown as blank in the 18th SCS catalog as was 9419 and 9420, two pieces of debris. However 9474, another piece of debris, has some "final" orbital parameters shown. It decayed from well over 800 km altitude (no pieces of debris with a perigee of over 800 km will decay naturally or by deorbit!) and 9483 was also shown as decayed - but with blanks for period, inclination, etc. Then there were two more pieces of debris (9484 and 9518) where again there were no orbital parameters shown. The image below is an Aug 2017 "screen scrape" of the satellite catalog. This indicates inadequate training, indifferent supervision. I will now replace this example with other examples since the DMSP orbits have been released again.

Other pages in this site:

Satellites With Low Perigees

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