First of all sorry for my immense ignorance in this matter and for all the stupid things I'll say here.

Yesterday, May 22th 2017, I removed the telescope from its dusty box1 and decided to watch Jupiter. After about 2 minutes of observation I spotted something across the sky [X-files music in background], it was a little less bright as Jupiter's "Galilean" moons2

Below you can se an accurate [Windows Paint] reconstuction of the fact I saw in my telescope. The red line indicates the direction of the thing (from right to left outside of the telescope).

Click to enlarge

Available data to help identify the object:

Time: May 22th, 2017 @ 22:12 UTC
My position: {
    Lat: 41.720194062015096
    Long: 12.713427287843729
    Sea level: 540 m
Direction: Probably South // The direction of Jupiter from that location at that time (did't had a compass)
Telescope: {
    Focal length: 700 mm
    Diameter: 60 mm
    Lens: H 20 mm

I only have data of the ISS and Iridium insights on an Android app3 so I am here to ask if there is some tool with which I can identify by myself as much satellites as possible across the sky.


  1. Winter is not nice with observers from here
  2. Not visible at naked eye
  3. I can almost certainly say that the "thing" was not teh ISS or one of the Iridium satellites

P.s: I will post here what the object was (with reference if possible) as soon as I identify it for curiouses like me.

  • $\begingroup$ One curious thing, checking the Heavens above site, Jupiter was quite well down in the SW at that time, so a LEO satellite would not have been in the sun at that time, in that direction. That would make it a lot dimmer than Jupiter's moons. $\endgroup$ – James K May 23 '17 at 21:25

This will be hard to track down. I'd suggest looking at something like SATVIEW Time Machine. I've entered the location and time you provided (I had to deviate by a few minutes to find something so maybe your time is not 100% accurate) and I can see there were a few satellites flying overhead. With enough work, you may be able to figure out which one was most likely the one you saw based on the Alt-Elev information detailed in the table.

There's plenty of other online satellite tracking websites out there, but keep in mind, most of them aren't going to have everything. And possibly, what you saw is in no database because it's a classified satellite in which case you probably won't find any record of it.

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  • $\begingroup$ Thank you so much!! The clock I use is only 5s late on the official GMT (I use time.is/GMT as a reference) so, combining your link with in-the-sky.org I can say...well, nothing! The most possible satellite from your reference could be SL-16 R/B but it isn't since it was on my location at about 90 deg at 22:05 UTC --- Two things that would help me are: 1) could you kindly indicate on my image where is the north? 2) What is the field of view of my telescope? $\endgroup$ – Cliff Burton May 29 '17 at 11:35
  • $\begingroup$ I just calculated the field of view of my telescope as 1.1 deg I hope I'm right!! And staring at Jupiter with 4 deg for 5 minutes from 22:10 UTC to 22:15 UTC nothing else passed on screen so I can say that it was a classified telescope at 100%! ...that's a joke, it is possible but the fact that there is no official non-classified satellites tracker makes it possible at any location in every single moment (I suppose). $\endgroup$ – Cliff Burton May 29 '17 at 11:43

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