Thanks so much Bob and Marco. Really just a curiosity, but it would have been fun to have witnessed it. Last night the HST flared by a couple of mags as it passed due north, but flares from the HST are nothing unusual. Cheers, Rob On 25/05/2023 08:22, Marco Langbroek wrote: > Op 25-5-2023 om 07:53 schreef Robert McNaught via Seesat-l: >> Examining my all-sky images from last night I was surprised to find >> that the crossing point of the HST (NORAD 20580) with a slightly >> brighter sat trail, which was ID'd as the pair TIANHUI 2-02A and B >> (NORAD 49071 and 49072), came within 1 second and a difference in >> slant range of only 10km. Just how close (in km) did these three sats >> come to each other? >> >> 2023 May 24 19:37:30UT > > > Using TLE's closest to your observing moment, I get these nominal > values (which have a +_ of at least 1 km, being TLE-based): > > > Output of my MultiCOLA software: > > approach threshold: 25 km start: 2023-05-24 00:00:00 UTC search > duration: 1.000 days > input number of targets: 3 input number of potential threaths: 3 > > DATE UTC DELTA D_ALT AGE-1 AGE-2 OBJECTS > 2023-05-24 18:02:27.13 21.643 6.915 +0.30 +0.55 > TIANHUI 2-02B to HST > 2023-05-24 18:02:27.15 21.307 7.253 +0.90 +0.55 > TIANHUI 2-02A to HST > 2023-05-24 18:50:01.21 24.105 5.513 +0.34 +0.58 > TIANHUI 2-02B to HST > 2023-05-24 18:50:01.22 23.555 5.179 +0.93 +0.58 > TIANHUI 2-02A to HST > 2023-05-24 19:37:30.33 ** 9.278 6.884 +0.37 +0.61 > TIANHUI 2-02B to HST > 2023-05-24 19:37:30.35 ** 9.857 7.222 +0.96 +0.61 > TIANHUI 2-02A to HST > 2023-05-24 20:25:04.40 6.467 5.559 +0.40 +0.65 > TIANHUI 2-02B to HST > 2023-05-24 20:25:04.41 6.461 5.225 +0.99 +0.65 > TIANHUI 2-02A to HST > > Near the moment of your observation they nominally came to 9.3 km > (Tianhui 2-02B) resp. 9.9 km (Tianhui 2-02A), with most of the > distance in altitude (6.0 resp 7.2 km). > > - Marco > > > ----- > Dr Marco Langbroek - SatTrackCam Leiden, the Netherlands. > e-mail: sattrackcam_at_langbroek.org > > launchtower: http://launchtower.langbroek.org > Station (b)log: http://sattrackcam.blogspot.com > Twitter: _at_Marco_Langbroek > ----- _______________________________________________ Seesat-l mailing list https://lists.seesatmail.org/mailman/listinfo/seesat-lReceived on Thu May 25 2023 - 21:21:51 UTC
This archive was generated by hypermail 2.4.0 : Fri May 26 2023 - 04:21:51 UTC