html code not working

[BlogSafe]

    <script>
        const ephemeris = new Ephemeris({
            year: 2000, month: 0, day: 1, hours: 0, minutes: 0, latitude: 41.37, longitude: -71.1, calculateShadows: false
        })
        ephemeris.Results;
    </script>
    
    gives: Ephemeris is not a constructor