Space and astronomy are related but distinct concepts. Astronomy is the scientific study of space; it focuses on observing and understanding celestial objects and phenomena. Space, on the other hand, is the vast expanse beyond Earth's atmosphere, encompassing all celestial bodies and the matter and energy within it. Essentially, astronomy studies space.
Astronomy: The Science of the Cosmos
Astronomy uses telescopes and other instruments to observe and analyze celestial objects like planets, stars, galaxies, nebulae, and comets. Astronomers study their properties, origins, evolution, and interactions. This involves a wide range of sub-disciplines including:
- Astrophysics: Applying physics principles to understand celestial objects and processes.
- Cosmology: Studying the origin, evolution, and large-scale structure of the universe.
- Planetary science: Focusing on planets and other bodies within our solar system and beyond.
As noted in several sources like Astronomy WA and this Quora answer, astronomy primarily relies on observation, often using specific wavelengths of light to gather data. The Cornell University graduate school program even lists "Astronomy - The general field of natural science..." as a focus of study within their Astronomy and Space Sciences program. (https://gradschool.cornell.edu/academics/fields-of-study/field/astronomy-and-space-sciences/)
Space: The Environment of Study
Space encompasses everything outside Earth's atmosphere. This includes:
- Celestial bodies: Planets, stars, galaxies, moons, asteroids, comets, etc.
- Matter and energy: Interstellar gas, dust, radiation, dark matter, dark energy.
- Physical phenomena: Gravity, magnetism, radiation, expansion of the universe.
Space is the arena in which astronomers conduct their research. It's also the focus of space science, which encompasses the exploration and utilization of space through technology, including space travel and satellite technology. Homework.Study.com explicitly states that "Astronomy is the scientific study of space," differentiating it from space science. (https://homework.study.com/explanation/is-space-science-the-same-as-astronomy.html)
In short, astronomy is the science that studies space. Space itself is the subject of study.
