Question

why star can't be variable in day and are smaller in size​

Answer 1

Answer:

here are a number of reasons for variability. These include changes in star luminosity or in star mass, and obstructions in the amount of light that reaches Earth. Pulsating variables swell and shrink. Eclipsing binaries get dimmer when a companion star moves in front, then brighten as the occulting star moves away.

Explanation:

Answer 2

1. BECAUSE THEY AREN'T BRIGHTER THAN THE SUN SO THEY CAN'T BE SEEN.
2. BECAUSE THEY AREN'T BRIGHTER THAN THE SUN SO THEY CAN'T BE SEEN.THEY ARE SMALLER IN SIZE BECAUSE THEY ARE TRILLIONS OF MILES AWAY.

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