Shooting stars occur so quickly and end before the blink of an eye so they are not great painting/drawing material. Digitally, there isn't much out there on creating them on a computer. A brush that just looks like a white line in the sky sums up their entire existence on the Internet, although there are millions of photos of them.
My test is "larger than life", and exaggerated, since they are merely a flash and not a comet. Is a white line enough? Does it matter? Who better to ask than the GIMP Chat gang? What say you?
No, no, please critique. The thing about art, aside from a kindergartner's crayola masterpieces (do not mistake pleasing with perfection), it is subject to everyone who looks at it. Wring this one out until it's ready to hang up.
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"In order to attain the impossible, one must attempt the absurd."
~ Miguel de Cervantes