What condition is necessary to see from Earth eclipses of stars in binary star systems?
A) The stars must have very similar surface temperatures, whatever the inclination of their orbital plane to the line of sight, to see a significant eclipse.
B) The line of sight from Earth to the star system must be very close to perpendicular to the orbital plane of the stars.
C) The line of sight from Earth to the star system must be in or very close to the orbital plane of the stars.
D) One of the stars must be much bigger than the other so that it can hide its smaller companion when the orbital plane is at a large angle to the line of sight.

Question

Quizplus · Accepted Answer

In order to see eclipses of stars in binary star systems, the Earth must be in or very close to the orbital plane of the stars. This is because the stars will appear to pass in front of each other only when viewed from a certain angle, which is within the orbital plane. If the Earth's line of sight is not in or very close to the orbital plane, the stars will not eclipse each other as seen from Earth.

What Condition Is Necessary to See from Earth Eclipses of Stars