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

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

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 zone controlled by an alien species
D) A region of space filled with gold

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

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

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

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

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