The past two months have seen sparse updates to my Space Flight Log. This is due to a major revision I have been running on the entire system.
Shortly after Christmas, I purchased a new monitor, a 49-inch curved display which allowed me to spread out the Log’s spreadsheets to where I could expand the thing horizontally.
The width of the Log’s sheets has always been limited by my desire to keep from scrolling horizontally while viewing a sheet. This has been further limited by my aging vision; I routinely run my displays scaled up to 125% of normal. The 49” monitor is no taller than its predecessors but is wonderfully wide, and its curvature makes it easy to look at the far edges.
Last summer, I attempted to add information on nationality of payloads and simple orbit parameters, placing them in the Remarks column. This was messy to read, even for me. Furthermore, I had a column labeled “Status” which also included the spacecraft’s decay date.
With the new monitor, I had plenty of room to add new columns. Specifically, I inserted columns for the two customary ID tags for payloads (COSPAR and NORAD), one for nationality of payload (often different from nationality of launch site), one for duration in orbit, and four for simple orbit parameters. I also split my Status column into Status and End Date.
The current list of columns is:
Launch Info: Designation
Launch Info: Launch Date
Launch Info: Launch Nation
Launch Info: Launch Vehicle
Launch Info: Launch Site
Launch Info: # of payloads in the launch
Payload Characteristics: Name
Payload Characteristics: COSPAR ID
Payload Characteristics: NORAD ID
Payload Characteristics: Nation
Payload Characteristics: Mission
Payload Characteristics: Mass
Payload Characteristics: Status
Payload Characteristics: End Date
Payload Characteristics: Duration
Payload Characteristics: Remarks
Orbit Data: Class
Orbit Data: Periapsis
Orbit Data: Inclination
Orbit Data: Period
Launch nation is, as always in my Log, the nation from which the mission was launched. In the case of sea and air launched rockets, this is the nationality of the owner and/or operator of the aircraft or sea launch platform.
The ID tags have been standard since the days of Sputnik and Vanguard.
Mass is always in kilograms.
End Date is the date on which the payload ended its flight through the sky. Occasionally, this is “Destroyed,” which means the craft broke into pieces while in orbit, whether accidentally or intentionally.
Duration is the number of days between the Launch Date and the End Date. When these are the same date, this number is zero.
Remarks have been trimmed considerably, since nationality and orbit have been placed elsewhere.
I moved Orbit Class over to Orbit Data, where it belongs. I kept this as a shorthand key, as I find it useful.
Periapsis and Apoapsis are the generic terms for the highest and lowest points of an orbit. I use them for simplicity. Technically speaking, perigee and apogee only refer to orbits around Earth—and there are a bunch of terms for these quantities when the Moon, the Sun, Mars, etc. are the primary body. Everyone agrees on perihelion and aphelion for solar orbits, but I’ve noticed at least four different pairs of terms for lunar ones.
I always use kilometers for periapsis and apoapsis, except when the orbit is solar, in which case I express it in astronomical units (1 AU=the mean distance between Earth and the Sun, or 149,597,870.7 km). Solar orbits of space probes aren’t always known, and for transfer orbits between Earth and another body they are often temporary and sometimes subject to change due to midcourse power maneuvers or close encounters with another planet (including, naturally, landings and impacts). There are five interplanetary probes which don’t orbit the Sun at all: Pioneer 10, Pioneer 11, both Voyagers, and New Horizons. All of these are on solar system escape trajectories. Properly speaking, they can be considered to orbit the center of the Milky Way, although I don’t think anyone has computed their orbits around our galaxy’s central black hole. Most likely, there should be little difference between those orbits and that of the Sun.
Period is usually expressed in minutes. For Earth orbits, when the period is significantly longer than one day, I also express it in solar days (1440 minutes).