Islip Art Museum???

Does anyone know what the name of the park is thats located right in back of the Islip Art Museum (on Irish Lane)? FH and I spotted it the other day and it looked really pretty. We actually pulled into the Museum entrance and drove around the the back and thats where the entrance to the park was I want to find out if its open all the time and if we can take pics there since its rigth across the street from our church practically.