Careful measurements reveal that a star maintains a steady apparent brightness at most times, except that at precise intervals of 73 hours the star becomes dimmer for about 2 hours. The most likely explanation is that:.1. The star is cepheid variable.2. The star is a member of binary eclipsing star system.3. The star is peridically ejecting gas into space every 73 hours.4. The star is a white dwarf.

2

The star is a member of a binary eclipsing star system.

Explanation:

Eclipsing binaries are the main source of determining a star's mass. A binary star system is essentially a system where two stars are orbiting around a common centre of mass. Eclipsing stars are studied by measuring their the changes in their brightness over a specified period of time. Light curves are graphical representation of the variations in stars over a given period of time.

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