[8bitsrule]

Longevity: The explanation on NASA's APOD page states:

" In low Earth orbit Fermi’s Large Area Telescope recorded gamma-ray photons from the burst for more than 10 hours as high-energy radiation from GRB 221009A swept over planet Earth last Sunday, October 9. "

while the second is more specific: "the afterglow of GRB 221009A faded over the course of about 10 hours."

Related interest: The Earth's atmosphere itself produces gamma flashes up to 20MeV:

https://en.wikipedia.org/wiki/Terrestrial_gamma-ray_flash

And: "Possible Role of Gamma Ray Bursts on Life Extinction in the Universe" (abstract only):

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.11...