Delta Scuti star
A Delta Scuti star is a classification of star.

Lieutenant Commander Una Chin-Riley made a firsthand observation of 99 Pegasi, a triple-mode high-amplitude Delta Scuti star when the  approached it within half a light year during her first deep space cruise aboard the ship.

She would later recall this to an envious Ensign Spock while they were stuck in a turbolift in 2254. ()

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Astronomical classifications