Found a Pigeon Egg!!!!

[nyc18]

I live in an apartment building and this morning I noticed a pigeon kept flying onto the terrace railing. At first I shooed it away b/c they usually do that from time to time but when it kept coming back, I spotted an egg underneath the table I have in the corner of the terrace. So I assume that is the mother that keeps coming back. So what should I do? I heard that if I touch it the mother won't want it anymore? The mother just watches the egg from the railing so does that mean she has yet to sit on it? Or is it about to hatch? Should I leave it alone since the mother is watching it? I don't want to interrupt any process the pigeon has to do but I don't want to see it die either. Thanks for any tips.