N2YO satellite tracking: Intelligence Source Guide 
CelesTrak / Space-Track: Intelligence Source Guide 
NOAA Aviation Weather Center API: Intelligence Source Guide 
AVWX REST API: Intelligence Source Guide 
hexdb.io: Intelligence Source Guide 
Space Intelligence (SPACEINT): Intelligence Discipline Guide
Orbits are deterministic and observable. A satellite cannot hide its manoeuvres from anyone willing to do the arithmetic, and much...
Signals Intelligence (SIGINT): Intelligence Discipline Guide
Signals intelligence is a state function with a warrant behind it. For everyone else, the discipline still matters, because you...
Radio Frequency Intelligence (RFINT): Intelligence Discipline Guide
The spectrum is a public utility with a public map. Licences, allocations and open receiver networks let you characterise the...
Measurement & Signature Intel (MASINT): Intelligence Discipline Guide
Imagery shows you the object. Measurement and signature intelligence tells you what the object is doing, how hot it is...
Technical Intelligence (TECHINT): Intelligence Discipline Guide
Every device carries a confession: certification filings, component markings, firmware strings and design choices. Technical intelligence reads that confession to...
Patent Intelligence (PATENTINT): Intelligence Discipline Guide
A patent is a bargain: an inventor gets a monopoly, and the public gets the working details. That trade makes...
Academic Intelligence (ACADINT): Intelligence Discipline Guide
Research output is the earliest public indicator of national and corporate capability. A capability appears in a paper years before...
Legal Intelligence (LEGINT): Intelligence Discipline Guide
Litigation is an involuntary disclosure engine. Adversaries in court say, under oath and on the public record, what they will...
Criminal Intelligence (CRIMINT): Intelligence Discipline Guide
Criminal intelligence is not case notes with better formatting. It is the discipline that turns scattered incidents into an articulable...
Energy Intelligence (ENERGYINT): Intelligence Discipline Guide
Energy is where physics, contracts and politics meet, and all three leave records. Energy intelligence reads the flows and the...