科か学がく観かん測そく衛えい星せい

Meanings

1

scientific research satellite

A satellite designed for scientific observation and data collection in space.

defense, protection

星star, spot, dot

人じん工こう衛えい星せい
人工衛星 is a general term for artificial satellites, while 科学観測衛星 specifically refers to those used for scientific observation.
気き象しょう衛えい星せい
気象衛星 is a weather satellite, a type of satellite focused on meteorological observation, whereas 科学観測衛星 covers a broader range of scientific research.

Compound of 科学 (science), 観測 (observation), and 衛星 (satellite).