No, there are not more possible legal moves in chess than there are atoms in the universe. While chess is a complex game with numerous possible moves, the number of possible legal moves is finite and calculable.
In chess, the number of possible moves depends on the position of the pieces on the board. On average, there are about 35 legal moves available to a player in a given position. However, the number of possible moves decreases as the game progresses and fewer pieces remain on the board.
In comparison, the estimated number of atoms in the observable universe is incredibly large, estimated to be around 10^80 (known as the Eddington number). This number is many orders of magnitude greater than the number of possible legal moves in chess.
It's worth noting that the number of unique chess games is astronomical. The number of possible chess games, taking into account all legal moves, is estimated to be around 10^120. This is known as the Shannon number, named after mathematician Claude Shannon. It represents the vast number of potential positions and moves in the game of chess, but it is still significantly smaller than the estimated number of atoms in the universe.