Q86.
Consider the following pairs : Objects in space Description 1. Cepheids : Giant clouds of dust and gas in space 2. Nebulae : Stars which brighten and dim periodically 3. Pulsars : Neutron stars that are formed when massive stars run out of fuel and collapse How many of the above pairs are correctly matched?
Answer
A
Explanation
also called Cepheid Variables, are stars which and dim periodically. This behavior allows to be used as cosmic yardsticks out to distances of few tens of millions of light-years. is a giant cloud of dust and gas in space. Some (more than one nebula) come from the gas and thrown out by the explosion of a dying star, such as supernova. Other nebulae are regions where new are beginning to form. For this reason, some are called "star nurseries. are rotating neutron stars observed to have of radiation at very regular intervals that typically from milliseconds to seconds. Neutron stars are when a massive star runs out of fuel and