2017 Solar Eclipse: The Moon and the Solar Corona

Solar Corona & Moon

Eclipsing Moon reveals the solar corona during The Great American Eclipse, 2017

  • Telescope: Stellarvue SVA130T-IS
  • Mount: Losmandy G-11 with Gemini 2 controller
  • Autoguiding: No
  • Optical Configuration: 0.72x field flattener & reducer (f/5); no solar filter during totality
  • Camera: Canon 60Da
  • Light Frame(s): Two-image composite of 1/30-sec and 1-sec exposures
  • Calibration: None (no darks, no flats, no biases)
  • Exposure Time: 1/30 sec + 1 sec
  • ISO: 100
  • Processing: Photoshop CC
  • Imaging Location: Prairie City, Ore.

This composite image reveals many lunar features and the solar corona during The Great American Eclipse of 2017. Super-heated plasma escaping from the sun creates the solar corona and becomes the solar wind that blows through our solar system at a million miles per hour. The charged particles that make up the coronal plasma follow the magnetic field lines of the sun and form streamers in the corona, like iron filings around a magnet. In this image, north is up, south is down, east is left, and west is right.

Sunlight reflecting from our Earth during the eclipse illuminates the Moon and bounces back to Earth as “earthshine.” Because of this earthshine, lunar features such as the “seas” and several large craters (Tycho, Copernicus, etc.) can be imaged during totality. The blue color of the Moon comes from our blue sky.