Your friendly neighborhood Buttermancer here to strongly recommend against running this card in The Circle Undone, given the huge amount of deck milling mechanics in that campaign. You'll whiff right past it at a million miles an hour. Probably twice after the encounter deck shuffles. You might draw it if you have encounter deck peeking shenanigans, but even then not reliably enough to make playing it worth the action.
In campaigns where the encounter deck is not flying off the table out the window, it looks pretty intriguing, probably strongest at 2 players given its unique requirements and effect. To elaborate, for one player, ten cards in the encounter deck is basically guaranteed, but play Stargazing halfway through a scenario and shuffle it into the bottom and you probably won't see it before the scenario is resolved. It does cancel 100% of spooky card bad stuff when it lands.
Two players probably have plenty of cards in the encounter deck and will draw the card within 5 turns, reasonable if it's at all early. It will cancel 50% spooky card draw for the team on the turn it lands. After that, it gets worse. It will be drawn very soon but only cancel a third of the encounter deck, and it will be drawn almost immediately but cancel the effect on 1/4th the team. It's actually a pretty good play on Farsighted (Mandy and Daisy can fit these, and Daisy has big hands potential synergy in Forbidden Tome).