NROL-85 elset update

From: Marco Langbroek via Seesat-l <>
Date: Mon, 18 Apr 2022 13:36:55 +0200
Updated preliminary NROL-85 elset, based on observations reported by Eelke 
Visser and me:

NROL-85 (USA 327)
1 70002U 22999A   22108.04497945 0.00000000  00000-0  00000+0 0    07
2 70002  63.5043 123.5866 0114230 185.9890 173.9785 13.40421486    07

rms 0.024 deg, from 21 observations Apr 17.83 - Apr 18.06 UT

This corresponds to a ~1193 x 1022 km orbit, 63.5 degree inclined.

Barring any large manoeuvres (which is always possible!), this elset should be 
good to within a few seconds coming night.

I suggest we keep looking for a second object in a wide time window around 
nominal pass times of this object.

So far, the apparent absence of a secondary payload is interesting. Either this 
is not an INTRUDER/NOSS mission after all; or it is an improved version of 
INTRUDER that now only needs one single satellite (they once started with 
three); or we somehow missed the second payload.

These kind of surprises is what keeps tracking interesting!

For new observers: your observations are very welcome, but a plea to report your 
observations in IOD format:

My "IOD Entry" software available at can help you 
to easily create IOD formatted datalines from your raw data.

- Marco

Dr Marco Langbroek  -  SatTrackCam Leiden, the Netherlands.

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Received on Mon Apr 18 2022 - 06:37:56 UTC

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