Dwarf Star

TESS is expected to launch on April 16th, 2018, The spacecraft will conduct an all-sky survey, starting with the Southern Hemisphere in its first year. MAny follow-up interstellar probes will be planned depending on its findings.

What could possibly cause a star to periodically increase its illumination when an object passes before? Lately, NASA has mentioned that it has found a dead star called a White Dwarf acting as a magnifying glass in space.