by Ann » Fri Nov 23, 2012 3:53 am
I note that the leonids in this picture, too, are very green, with no trace of blue. Their color is similar to the color of the leonid in APOD November 22, 2012. Admittedly, the APOD of November 19, 2012, is just possibly slightly blue-deficient, or at least possibly more so than the APOD of November 22. The stars in the APOD of November 19 almost all very white, whereas in the APOD of November 22 they are typically bluish-white.
Brightness could play a part here. The stars in the APOD of November 19 look quite bright, whereas in the APOD of November 22 they look rather faint. Some photographers and some photographic films "burn out" the blue color of bright bluish stars, while they enhance the (possibly more intrinsically not so blue) blue color of faint stars. The APOD of November 19 could be an example of that kind of astrophotography.
I'm just speculating somewhat idly about the cause of the strikingly green, totally non-blue color of these leonids.
Ann
I note that the leonids in this picture, too, are very green, with no trace of blue. Their color is similar to the color of the leonid in APOD November 22, 2012. Admittedly, the APOD of November 19, 2012, is just possibly slightly blue-deficient, or at least possibly more so than the APOD of November 22. The stars in the APOD of November 19 almost all very white, whereas in the APOD of November 22 they are typically bluish-white.
Brightness could play a part here. The stars in the APOD of November 19 look quite bright, whereas in the APOD of November 22 they look rather faint. Some photographers and some photographic films "burn out" the blue color of bright bluish stars, while they enhance the (possibly more intrinsically not so blue) blue color of faint stars. The APOD of November 19 could be an example of that kind of astrophotography.
I'm just speculating somewhat idly about the cause of the strikingly green, totally non-blue color of these leonids.
Ann