Conjunction Event Detail

    Very Low Risk
    Very low collision probability. Continue monitoring.
    9.222325E-7
    Collision Probability (Pc)
    Last Conjunction Event Update Time 2026-09-03T08:35:53+0800
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    1 Object 1

    Name USA 55
    AOE ID 20547
    NORAD ID 20547
    Object Type PAYLOAD
    Country
    US US
    VS

    2 Object 2

    AOE ID 52630
    NORAD ID 52630
    Object Type PAYLOAD
    Country
    US US

    Conjunction Constraints

    Parameter USA 55 STARLINK-3989
    Time of Closest Approach 2026-09-04T11:23:49+0000
    Collision Probability (Pc) 9.222325E-7
    Conjunction Distance (km) 2.624 km
    Relative Speed (km/s) 5.575 km/s
    Conjunction Risk Parameters R (Radial): 0.636 | I (In-track): 2.375 | C (Cross-track): -0.917
    Collision Risk Index (CRI) 0.34
    X Position (km) -6525.506 -6525.347
    Position Y (km) -799.463 -800.188
    Position Z (km) 1911.489 1914.006
    Velocity X (km/s) 2.052 2.243
    Velocity Y (km/s) 0.821 -4.526
    Velocity Z (km/s) 7.284 5.723

    Orbital Parameters 国际轨道数据源

    Parameter USA 55 STARLINK-3989
    Semimajor Axis (a) 6809.906 km 6848.869 km
    Eccentricity (e) 0.005359 0.000118
    Inclination (i) 94.0951° 53.1588°
    RAAN 187.1157° 185.3399°
    Perigee Argument 192.5967° 86.2087°
    Mean Anomaly (M) 167.3954° 273.9049°
    Apogee 468.264 km 471.542 km
    Perigee 395.274 km 469.922 km
    Orbit Epoch 2026-09-02T14:14:32+0000 2026-09-02T02:55:55+0000

    USA 55 & STARLINK-3989 Collision Probability (Pc) Trend

    USA 55 & STARLINK-3989 Collision Probability (Pc) TrendNot Available

    USA 55 & STARLINK-3989 Miss Distance (Miss Distance) Trend

    USA 55 & STARLINK-3989 Miss Distance (Miss Distance) TrendNot Available

    USA 55Miss Distance Trend with All Objects

    Object 1 Miss Distance TrendNot Available

    STARLINK-3989Miss Distance Trend with All Objects

    Object 2 Miss Distance TrendNot Available

    USA 55Collision Probability Trend

    Object 1 Probability TrendNot Available

    STARLINK-3989Collision Probability Trend

    Object 2 Probability TrendNot Available

    Nearby Objects with USA 55

    No nearby objects data