Heat Pump Defrost Question

https://andrerdzu732.birchreport.com/posts/repair-or-replace-your-ac-in-north-fort-worth-with-advice-from-comfort-experts-2

Heat Pump Defrost Question Is it normal for a heat pump to blow steam from the outdoor unit in winter? Ours did that during the freeze last February and I panicked a bit. Sounds like it might just be the defrost cycle from what I'm reading here