Keep every mission.
Query all of it, anytime.

-- Compute closest approaches between any two tracked objects
-- in the last hour, surfacing pairs under a 5km screening threshold.
WITH positions AS (
  SELECT
    norad_id,
    object_name,
    timestamp,
    position_eci_x,
    position_eci_y,
    position_eci_z,
    velocity_kmps
  FROM space.telemetry
  WHERE timestamp > NOW() - INTERVAL '1 hour'
    AND orbit_class IN ('LEO', 'MEO')
)
SELECT
  a.object_name as primary,
  b.object_name as secondary,
  DATE_TRUNC('minute', a.timestamp) as minute,
  SQRT(
    POWER(a.position_eci_x - b.position_eci_x, 2) +
    POWER(a.position_eci_y - b.position_eci_y, 2) +
    POWER(a.position_eci_z - b.position_eci_z, 2)
  ) as separation_km,
  ABS(a.velocity_kmps - b.velocity_kmps) as relative_velocity_kmps
FROM positions a
JOIN positions b
  ON a.norad_id < b.norad_id
  AND a.timestamp = b.timestamp
WHERE SQRT(
    POWER(a.position_eci_x - b.position_eci_x, 2) +
    POWER(a.position_eci_y - b.position_eci_y, 2) +
    POWER(a.position_eci_z - b.position_eci_z, 2)
  ) < 5.0
ORDER BY separation_km ASC
LIMIT 100;