In a previous life, I laser scanned historic sites. Castles, cityscapes, industrial heritage and so on.
If you want something that sounds cool and interesting but is, in reality, tedious and boring, this is it.
Let me up the pedantry stakes...
You are correct in that light in a vacuum is the measured and fastest "Speed of light". But the light in the atmosphere, whilst slower, is still the speed of light. Also underwater - a different speed but still the speed of light.
It's like the speed of Usain Bolt. He's been measured doing 100 metres in ideal conditions. Make him wear an oodie and flip flops and run it again, it would be slower but would still be his speed.
Visiting my mum today, she gave my daughter a 50p coin with Charles's face on it. Mum then said, "if the news is right, we might get a coronation soon. The king isn't well."
My daughter replied "It's fine. He's old, like in his nineties anyway."
Lack of empathy for the royals from my youngest.
When I was a teenager, a pal's mum had a hysterectomy.
Her best pal visited when she got home and asked "So, what does it feel like to be half a woman?"
Women are brutal at times.