What field of science investigates ideas about life extraterrestial?

Would guns work on the moon? What kind of clouds are light and feathery? What is the worlds biggest rocket? What does the big star on China's flag represent? When is the next space shuttle taking off? How do you improve accelaration of a rocket in space? How many stars make up the constellation volans? How are you supposed to be chosen to go to space? How do scientists see what early galaxies looked like? What does Walk Among the Stars mean? How is a star's life cycle determined? What each shuttle mission has as a specially trained of astrounauts? How do you get a moon chao? An instrument used to view different colors of light produced by each type of light bulb is called a? What does it mean when you feel like something is moving in your stomach? What gases did the atmosphere consist of? What is the white jacket that Kevin gates wears in the satellites? Where in the country does the sun shine the most? Why is atmosphere more dense at sea level than a mountain top? What are the Minor gases on Mercury?

What field of science investigates ideas about life extraterrestial?