# Re: UNID crossing the Moon

From: Björn Gimle (bjorn.gimle@gmail.com)
Date: Wed Oct 12 2011 - 16:53:11 UTC

• Next message: Bram Dorreman: "Re: Slow tumbling sat"

```It would be interesting to see a still image, and how you arrived at the 4"
size.

But even more useful for identification of a possible/likely satellite is
the exact time of passage!

2011/10/12 Giuseppe N. Gerbore <giuseppegerbore@virgilio.it>

> Yesterday night I captured by chance something crossing the Moon:
>
> Seems to me a satellite, but .. let us do some calculation:
>
> Data:
>
> Image angle                4''
>
> Captured path             15'
>
> Transit time                1.93s
>
>
>
> By using the approximate relation: sin(A)=Diametre/Range:
>
>
>
> 1) Plane (D=50m)                  Range             =50/sin(4'')
>       =2 578 310 m
>
>                                               Path
>  =50*60*15/4              =      11 250 m
>
>                                               Velocity          =11
> 250/1.93              =       5 829 m/s
>
> 2) Satellite (D=10m)             Range             =10/sin(4'')
>     =   515 662 m
>
>                                               Path
>  =10*60*15/4              =       2 250 m
>
>                                               Velocity          =2 250/1.93
>                =       1 165 m/s
>
> 3)Bird (D=0.3m)                    Range             =0.3/sin(4'')
>        =     15 469 m
>
>                                               Path
>  =0.3*60*15/4             =          67.5 m
>
>                                               Velocity          =67.5/1.93
>                  =         34.9 m/s
>
> 4) Mosquito (D=0.005m)       Range             =0.005/sin(4'')           =
>           257 m
>
>                                               Path
>  =0.005*60*15/4         =        1.125 m
>
>                                               Velocity          =1 125/1.93
>                =          0.58 m/s
>
>
>
> Velocity assumed at right angle with line of sight. Might be much more if
> object approaching or moving away from the observer.
>
>
>
> Am I talking complete nonsense?
>
>
>
>
>
> Giuseppe
>
>
>
> Casa, 44.64°N, 10.90°E, 57m asl.
>
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--
----------------------------------------
Björn Gimle, COSPAR 5919
59.2576 N, 18.6172 E, 23 m
Phone: +46 (0)8 571 43 312
Mobile: +46 (0) 704 385 486
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