Astronomers study the fundamental processes at play in the cosmos at the level of stars and planets. They further their understanding by using ground base and space telescope observations. There are many areas where astronomy and astrophysics intersect, and astrophysics aims to connect what physics says about how the Universe works with what we see in the universe around us.
Astrophysicists investigate the cosmos and offer justifications for its existence. University researchers and government agencies conduct the majority of astrophysics research. As teachers at colleges, astronomers—among whom astrophysicists are sometimes included—often divide their time between research using data from observatories, constructing models, and teaching.
Even though some astronomers visit observatories to collect their data, they frequently only do so for a few weeks a year, leaving the rest of the year to interpret it. In general, theoretical astronomers will never conduct observations but rather compare their models with existing ones. Astrophysicists conduct research that is subsequently published in academic journals.
Astrophysicists are highly educated and skilled in a variety of fields but usually work only in one of them. As you would guess from the name, they heavily rely on physics in their work. According to NASA, the mission of an astrophysicist is to "understand how the universe functions, examine how it began and evolved, and hunt for life on planets surrounding other stars."