Conjunction Event Detail

    Low Risk
    Low collision probability. Continue monitoring.
    1.55526E-6
    Collision Probability (Pc)
    Last Conjunction Event Update Time 2026-09-11T21:03:46+0800
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    1 Object 1

    Name USA 77
    AOE ID 21809
    NORAD ID 21809
    Object Type PAYLOAD
    Country
    US US
    VS

    2 Object 2

    AOE ID 51843
    NORAD ID 51843
    Object Type UNKNOWN
    Country
    CN CN

    Conjunction Constraints

    Parameter USA 77 OBJECT V
    Time of Closest Approach 2026-09-12T19:07:35+0000
    Collision Probability (Pc) 1.55526E-6
    Conjunction Distance (km) 2.276 km
    Relative Speed (km/s) 8.924 km/s
    Conjunction Risk Parameters R (Radial): 0.407 | I (In-track): -1.803 | C (Cross-track): -1.326
    Collision Risk Index (CRI) 0.39
    X Position (km) 3320.799 3322.281
    Position Y (km) -1578.632 -1580.157
    Position Z (km) 5665.197 5664.388
    Velocity X (km/s) -0.622 -6.434
    Velocity Y (km/s) 7.627 1.062
    Velocity Z (km/s) 2.396 4.057

    Orbital Parameters 国际轨道数据源

    Parameter USA 77 OBJECT V
    Semimajor Axis (a) 7424.542 km 6757.862 km
    Eccentricity (e) 0.089908 0.000504
    Inclination (i) 63.2947° 97.3495°
    RAAN 288.2815° 344.4848°
    Perigee Argument 76.3271° 193.3352°
    Mean Anomaly (M) 293.6137° 166.7774°
    Apogee 1713.928 km 383.130 km
    Perigee 378.882 km 376.320 km
    Orbit Epoch 2026-09-11T02:09:02+0000 2026-09-11T07:32:09+0000

    USA 77 & OBJECT V Collision Probability (Pc) Trend

    USA 77 & OBJECT V Collision Probability (Pc) TrendNot Available

    USA 77 & OBJECT V Miss Distance (Miss Distance) Trend

    USA 77 & OBJECT V Miss Distance (Miss Distance) TrendNot Available

    USA 77Miss Distance Trend with All Objects

    Object 1 Miss Distance TrendNot Available

    OBJECT VMiss Distance Trend with All Objects

    Object 2 Miss Distance TrendNot Available

    USA 77Collision Probability Trend

    Object 1 Probability TrendNot Available

    OBJECT VCollision Probability Trend

    Object 2 Probability TrendNot Available

    Nearby Objects with USA 77

    No nearby objects data