Solar Eclipse Maestro Icon

Baily’s Beads Close-Up Animation Window

The window displays the Baily’s beads close-up animation at each of the contacts during the eclipse as seen from your location. The animation enables you to simulate the Baily’s beads and view their position and shape.

  1. Choose Display > Baily’s Beads Close-Up Animation…
    Eclipse Contact Close-Up Baily Bead Animation Window
    Eclipse Baily Bead Close-Up Animation Contextual Menu
Eclipse contact times, magnitude and duration of totality or annularity all depend on the angular diameters and relative velocities of the Moon and Sun. The Moon exhibits an irregular limb when seen in profile, due to its surface topography. Most eclipse calculations assume some mean radius that averages high mountain peaks and low valleys along the Moon’s rugged limb. Kaguya and Lunar Reconnaissance Orbiter probe data or Watts charts are used for higher accuracy in those calculations. Watts charts are nowadays obsolete and shouldn’t be used anymore. The radial scale of the limb profile in the figure is exaggerated so that the true limb’s departure from the mean lunar limb is readily apparent.
The position angles of the second and third contacts are clearly marked with orange and green arrows (when dotted it’s the position of the corrected contacts) along with the north pole of the Moon’s axis of rotation as a blue arrow extended by a green tick mark, the north pole of the Sun’s axis of rotation as a yellow and the observer’s zenith at maximum eclipse indicated by a mauve arrow. A graduated compass with an origin at the zenith is displayed in mauve and another in blue for the northern lunar pole.

A contextual menu, that can be invoked with a right click, will let you select various options:
  • Solar Diameter
    • 2000 pixels - 2000 pixels
    • 1000 pixels - 1000 pixels
    • 600 pixels - 600 pixels
  • Display the Chromosphere in H-α - Enable the display of the chromosphere in H-α where its height is much higher than in white light.
  • Continue Animation - Play the animation that was stopped.
  • Stop Animation - Halt the running animation.
  • Replay Animation - Start the animation from the beginning.
  • Play Animation in Loop - When the animation is finished, it will be restarted from the beginning.
  • Movie Size (Width by Height)
    • 800x350 pixels - 800 by 350 pixels
    • 1024x350 pixels - 1024 by 350 pixels
    • 1024x800 pixels - 1024 by 800 pixels
    • 1280x350 pixels - 1280 by 350 pixels
    • 1280x720 pixels - 1280 by 720 pixels (HD)
    • 1920x1080 pixels - 1920 by 1080 pixels (HD)
    • 800x800 pixels - 800 by 800 pixels
    • 1200x1200 pixels - 1200 by 1200 pixels
    • 2200x2200 pixels - 2200 by 2200 pixels
    • Current Window Size - Use the current window size
  • Save As QuickTime Animation… - Lets you create a QuickTime movie containing the animation. The animation is created by a background task and a progression window is displayed.
  • Save Image As PNG File… - Lets you create a PNG image file containing the simulation at the current time. This menu item is enabled only when the animation is stopped/paused.
  • Height Exaggeration Factor - Select the lunar height exaggeration from one to twenty times. By default it’s drawn to scale.
  • Display Baily Beads Intensity - Enable the display of the Baily’s beads positions and shapes during a total or beaded eclipse.
  • Display Solar Limb Darkening - Enable the display of the solar limb darkening.
  • Filtering Factor - To simulate the use of a solar filter from ND1 to ND5.
When hovering over the window a time slider appears. The slider can be used to display the Baily’s beads at a specific time around the contacts.

Note: for an annular eclipse only the smallest beads, the ones at second and third contacts, are displayed.