I haven’t posted any online updates to the Log since May 6, as I have been adding new data to the entire log, from 1958 through 2022. Specifically, I’ve added basic orbital information (perigee and apogee in kilometers, inclination in degrees, and orbital period in minutes). This information was taken from Spacetrack on May 6, so all this info is effectively Epoch 2023-05-06. I have placed this data in the Remarks column in the following format:
Orbit perigee-apogee-inclination-period
This seemed a far better idea than inserting four extra columns. I did this only for objects remaining in orbit as of the epoch.
The idea is to give readers a good idea of the current orbit. I have ignored any payload which has reentered or landed, as orbital data for those is difficult to obtain reliably. Spacetrack includes these parameters in their list of decayed objects; however, they give the last known orbit for the spacecraft, not the initial operating orbit.
This is done only for geocentric orbits, as Spacetrack does not keep orbital parameters for any others. It is not currently possible to directly observe spacecraft (or anything else smaller than a few meters) in orbits around the Sun, the Moon, or any of the planets. Indeed, it has been comparatively recently that they have published current orbital parameters for craft significantly farther out than the geostationary zone.
I haven’t included any orbital data for recent launches (that is, after 2022-12-31). It often takes satellites several days to a few months to reach their operating orbits. This is particularly true of Starlink, One Web, and many geosynchronous birds. In the future, I intend to insert new data every few months, probably using a lag of four to six months to give many spacecraft a chance to reach their operational positions.
I first got the idea to do this because I was curious as to whether a given satellite was likely to reenter the atmosphere soon (a general rule of thumb is that if the perigee is less than 200 kilometers, the bird will reenter in a matter of months, if not weeks or days). I do not intend to constantly update this information, however, as that is quite laborious. It took over two weeks to insert the current round of data, after all. In the future, I may look back at the oldest orbiting satellites (probably pre-1970) once a year and add in their latest orbital parameters to the Remarks column.