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ELI5: Why can I pour oil into boiling water, but water poured into hot oil explodes into the air?

I was making pasta and sauteeing chicken recently.  I poured olive oil into the pasta water and it was totally fine, and then a drop of water fell into the chicken pan and popped up into the air.  Why, science, why?

Edit: Thanks for all the responses, people!
gpt
The main thing that's going on is that water boils at 100^o Celcius.

Hot oil is often much hotter than 100^o C. Typically oils will start to burn, depending on the oil you're using, at around the 200^o C mark, give or take. So when you see smoke coming from the oil you're at those sorts of temperatures.

Typically you don't cook with the oil actually burning (unless you're a bit of a dodgy chef), and you're likely going to be at around the 160-180^o C sort of area.

What this means is that when you drop water into hot oil it evaporates pretty much instantly. The temperature of the oil is above the boiling point of water. The explosion is the rapid generation of steam caused by this near-instant evaporation. This steam throws some oil up into the air aswell, just because the gas expands so quickly.

Also, oils tend to have a relatively high heat capacity, and you've got the heat in the metal of the pot/pan aswell. This means that you can evaporate a fair bit of water without losing too much heat in the oil. So there's some potential for relatively large explosions if you drop a lot of water in.

Obviously, in the reverse situation, the water can't be hotter than 100^o C (for pure water anyway - adding salt does change the boiling point a bit). Oils won't evaporate (edit: or decompose) at that temperature, so no gas is being generated, so no explosion happens.