by GoatGuy » Sun Nov 19, 2023 5:38 pm
What a marvelous image! Thank you. Being an incurable mathemaholic, I asked myself "I wonder what the actual solar face transit time is, from someplace more-or-less underneath (Sea level)". Doesn't require that much math, (and no … cheαting by way of Google isn't the point), but it does require some geometric thinking. One can look up the relevant constants (G = 9.80665 m/s²), distance to Sol is (149.5×10⁹ m distant), distance to International space station is about nominally (400×10³ m). After all that, I got 0.485 seconds.
Definitely "a fraction of a second". Man, you have to be really, really quick to get the picture of the transiting ISS station.
This kind of calculation makes me smile for hours: it numerically delineates the window of difficulty of one's future endeavor, should you or me or a young photo-astronomer want to duplicate the effort. Of course, it is also just the tip of the iceberg (numerically). One needs to know the orbital parameters of the ISS to at least 6 digits of precision, the rotation of Terra to the same degree, one's latitude and longitude to the SAME degree. Then figure out just exactly when such a window of opportunity might afford itself in the next year, because I suspect that getting this shot requires at least a year's worth of mismatched transits-versus-longitude-and-latitude to come and go.
BRAVO. I am amazed! Thank you again.
Bob Lynch
AKA GoatGuy around the net.
What a marvelous image! Thank you. Being an incurable mathemaholic, I asked myself "[i]I wonder what the actual solar face transit time is, from someplace more-or-less underneath (Sea level)"[/i]. Doesn't require that much math, (and no … cheαting by way of Google isn't the point), but it does require some geometric thinking. One can look up the relevant constants (G = 9.80665 m/s²), distance to Sol is (149.5×10⁹ m distant), distance to International space station is about nominally (400×10³ m). After all that, I got 0.485 seconds.
Definitely "a fraction of a second". Man, you have to be really, really quick to get the picture of the transiting ISS station.
This kind of calculation makes me smile for hours: it numerically delineates the window of difficulty of one's future endeavor, should you or me or a young photo-astronomer want to duplicate the effort. Of course, it is also just the tip of the iceberg (numerically). One needs to know the orbital parameters of the ISS to at least 6 digits of precision, the rotation of Terra to the same degree, one's latitude and longitude to the SAME degree. Then figure out just exactly when such a window of opportunity might afford itself in the next year, because I suspect that getting this shot requires at least a year's worth of mismatched transits-versus-longitude-and-latitude to come and go.
BRAVO. I am [b]amazed[/b]! Thank you again.
Bob Lynch
AKA [b]Goat[/b]Guy around the net.