Answer:
1: two 2: wobble 3: eclipsing
Step-by-step explanation:
A binary star system is made of two stars, one of which is brighter than the other. Astronomers are able to detect the dimmer star because its gravity causes the bright star to wobble. Astronomers can also spot the dimmer star by observing a phenomenon called a(n) eclipsing binary. This happens when the dim star passes in front of the bright star.