“Once the twinkle was removed, the light from the star itself was blocked using the team's coronograph, an instrument that selectively masks out the star.”

“Figure 1: The solar corona and the solar wind observed by a SECCHI coronagraph on a STEREO probe.”

“In other words, a coronagraph produces an artificial solar eclipse.”

“In 1930 the French astronomer Bernard Lyot invented the coronagraph, a specialized telescope that produces an artificial eclipse of the Sun.”