Data Comparison

The numbers won't match — and that's normal

• Different populations. Space-Track counts every catalogued object still on orbit (payloads, rocket bodies and debris); NAZAR's CelesTrak bundle is trimmed to active payloads, so it reads much lower.
• Different clocks. Space-Track publishes continuously; NAZAR's CelesTrak snapshots refresh on a schedule, so one can lag the other by hours.
• Different screening. Space-Track CDMs use high-precision orbits not released publicly; CelesTrak SOCRATES screens the public TLEs — same physics, coarser inputs.
• Naming and attribution lag. New launches can sit un-named or mis-flagged in either catalogue for days (see the catalogue-gap panel on Sat-Stats).