A) Neptune
B) Saturn
C) Jupiter
D) Mars

A) A type of space telescope
B) A substance that provides scientific evidence of past or present life
C) An alien language
D) A signal from outer space

A) The habitable zone around a star where conditions are just right for life
B) The area where space missions look for extraterrestrial life
C) A region of space filled with gold
D) A zone controlled by an alien species

A) The first message from aliens
B) A theory about the origin of the universe
C) A strong narrowband radio signal detected by astronomer Jerry R. Ehman in 1977
D) A code used by space agencies

A) Because extremophiles show that life can exist in extreme environments
B) Because they are alien species
C) Because they are immune to cosmic radiation
D) Because they provide energy to spacecraft

A) A hypothetical megastructure that completely surrounds a star and captures its energy
B) A method of communication with aliens
C) A type of exoplanet
D) A new type of telescope for deep space exploration

A) A rotating neutron star that emits beams of electromagnetic radiation
B) A type of planet with extreme weather
C) A celestial event marking the birth of a star
D) An alien spacecraft

A) A directory of alien species
B) A guide to space exploration equipment
C) A database of known exoplanets that are considered potentially habitable
D) A list of potential candidates for space colonization

A) Calculating spaceship speeds
B) Estimating the number of active, communicative extraterrestrial civilizations in the Milky Way galaxy
C) Determining ocean temperatures on exoplanets
D) Predicting comets' trajectories