The title (likely intentionally) is misleading, it should say "travelling faster than light in a medium". Nothing here travels faster than light in vacuum.

BTW there are special types of telescopes used to observe gamma rays - they cannot see gamma ray directly but observe a flash of Cherenkov light of a cascade of charged particles created when gamma ray hits atoms in the atmosphere. Those telescopes are Imaging Atmospheric Cherenkov Telescopes [1].

1. https://en.wikipedia.org/wiki/MAGIC_(telescope) or https://en.wikipedia.org/wiki/VERITAS or https://en.wikipedia.org/wiki/High_Energy_Stereoscopic_Syste... or https://en.wikipedia.org/wiki/Cherenkov_Telescope_Array_Obse...

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Betelbuddy 32 minutes ago | parent [-]

>> The title (likely intentionally) is misleading,

That is because that is not the title...the title is: "What is Cherenkov Radiation?"

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mmmattt 15 minutes ago | parent [-]

He obviously meant the title of the HN post? Why not straight up say that the article title is different and avoid the passive aggressiveness.

	▲	Betelbuddy 4 minutes ago \| parent [-]
		I did not meant it in that way...and I would bet, most did not interpret it as such...the passive aggressiveness is coming from you. I meant it that the poster, changed the original title, what is a kind of editorializing. I thought of calling on the mods to edit it back, but judged that would be a kind of... semi-passive aggressiveness.