Sorry if this is a naive question, and I have searched to no avail to try to find the answer, and checked on more than one broker. It's about 12 noon EST on Friday Feb 21 - there are no 0DTE options available for NDX (nasdaq index options), the earliest on the option chain is for Monday 2/23 3DTE. Can someone give me some clarity as to why that is? Much appreciate in advance any help in learning,, thank you.