<canvas id="sky"></canvas> const canvas = document.getElementById('sky'); const ctx = canvas.getContext('2d', { alpha: true }); const speedSlider = document.getElementById('speed'); const showOrbits = document.getElementById('showOrbits'); const showMoonOrbits = document.getElementById('showMoonOrbits'); const showLabels = document.getElementById('showLabels'); const showKuiper = document.getElementById('showKuiper');