How Do Blacklights Make Things Glow? đĄ
Morning Durd!

1) Why are you in your bedroom in the opening graphic? Thatâs weird and not how we do this.
2) Why do you look like youâre hiding something from us?

Nope.
Black light him.

Oh my god.
I had a feeling you had a problem after the âhow do twins happenâ newsletter.
But weâre here to learn, not judge.
So how do blacklights make things glow?
Cause surely youâve been there too.
Youâre seal team 6-ing some friday night laser tag with your pals:

Itâs smoky in there so you huddle up.

And right when you get under that black light, your team sees it.

YaaaaâŚ
Thatâs last monthâs chili stains, your uncontrolled dandruff problem, and a huge pee mark from that time you were on a roadtrip and mom asked you eight times if you had to stop to go to the bathroom and you assured her you didnât because you had a âsteel bladderâ and then you had to prove that you did, in fact, have a steel bladder so you started chugging every last liquid in the car and then mom stopped asking if you needed to stop because she also wanted to prove that she knew you had to go the fourth time she asked so then it was a game of chicken for who would crack first and you wouldnât dare let your mom be right so you just let a rip all over yourself.
Ya.
So whatâs going on?
Well black light is like any other light, but it mostly emits ultraviolet (UV) light.
A part of the electromagnetic spectrum our eyes arenât tuned to see.

So we just see a faint, purplish glow.
Now most things a black light shines on stay dark.
But some stains glow super bright.
And thatâs because those stains contain compounds called phosphors.

A thing that absorbs UV electromagnetic energy, then ~fluoresces~.


Basically it emits the energy it absorbed right back.
So when you shine a black light on a phosphor, youâre getting that object to convert invisible UV light into visible light we can see!


Highlighter ink, neon paint, human teeth, (and whatever Durd was doing in his bedroom) all contain natural phosphors!
Stay Cute,
Henry & Dylan đ
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