Total number of cataloged objects currently being tracked in Earth orbit, including active satellites, defunct satellites, rocket bodies, and debris fragments.
0
Updated in real-time from TLE
TLE (Two-Line Element set) is a standardized data format used to describe the orbit of an Earth-orbiting object. Published by the US Space Command, TLEs enable prediction of an object's position at any given time.
data
Active Conjunctions (24h)?
A conjunction occurs when two objects in orbit pass close to each other (within 1km). These events are monitored continuously to assess collision risk and determine if avoidance maneuvers are needed.
0
Predicted close approaches < 1km
Fragmentation Events (30d)?
A fragmentation event occurs when a space object breaks apart — from collisions, explosions, battery failures, or material degradation — creating multiple new trackable debris pieces.
3
🔴 2026-02-18 — SL-16 R/B breakup
Proton upper stage (1993-015B) spontaneous breakup at 850km due to residual propellant. +23 fragments cataloged.
🟠 2026-02-09 — CZ-3B R/B debris shed
Long March 3B upper stage (2019-074B) thermal cycling stress fragmentation at 780km. +15 fragments.
🟡 2026-01-28 — Unknown breakup
Unidentified object near 920km / 99° inc. Possible micrometeorite impact. +9 fragments detected by 18th SDS.
Orbit Distribution
LEO (200–2,000 km)0
MEO (2,000–35,786 km)0
GEO (~35,786 km)0
HEO / Other0
Kessler Risk Index?
The Kessler Syndrome describes a cascading chain reaction where collisions create debris that causes further collisions. This index estimates the current risk level for each orbital regime based on object density and relative velocities.
LEO
MEO
GEO
HEO
MODERATE
800-1000km altitude band: HIGH object density
⚡ Collision Probability?
Estimates the probability that two specific objects will collide within a given time window. Free version includes 50 sample objects; PRO unlocks the full Space-Track catalog (45,000+ objects).
Object 1 (NORAD ID or name)
Object 2 (NORAD ID or name)
Time Window
Min. miss distance—
Relative velocity—
TCA—
—
—
How is this calculated?
Uses a simplified Kessler spatial density model: collision probability = 1 − exp(−V_rel × σ / V_shell × N_orbits), where V_rel is relative velocity from orbital elements, σ is combined cross-section, and V_shell is the shared orbital shell volume. For production use, PRO version applies SGP4 orbit propagation with Alfano's method using full covariance matrices.
🔒 PRO — COMING SOON Full Space-Track Catalog (45,000+ objects) Monte Carlo · Covariance Realism · Maneuver Planning
Data Sources?
Orbital data comes from publicly available catalogs maintained by the US Space Command via Space-Track.org, ESA's DISCOS database, and conjunction data messages (CDMs) from CSpOC.
Space-Track.org TLE catalog CSpOC conjunction data ESA DISCOS database