History

An astronaut (or cosmonaut) is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft.

Although generally reserved for professional space travelers, the terms are sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and tourists.
 

An astronaut (or cosmonaut) is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft.

Although generally reserved for professional space travelers, the terms are sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and tourists.

An astronomer is a scientist in the field of astronomy who studies stars, planets, moons, comets, and galaxies, as well as many other celestial objects.

A related but distinct subject, cosmology, is concerned with studying the universe as a whole. An astronomer researches the world beyond Earth.

A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and carefully describe the properties in terms of quantities, with detail on the level of molecules and their component atoms. In addition, chemists carefully measure substance proportions, chemical reaction rates, and other chemical properties.

A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and carefully describe the properties in terms of quantities, with detail on the level of molecules and their component atoms. In addition, chemists carefully measure substance proportions, chemical reaction rates, and other chemical properties.

A computer scientist is a person who has acquired the knowledge of computer science, the study of the theoretical foundations of information and computation and their application. Computer scientists typically work on the theoretical side of computer systems instead of the hardware side on which computer engineers mainly focus (although there is overlap). 

A computer scientist is a person who has acquired the knowledge of computer science, the study of the theoretical foundations of information and computation and their application. Computer scientists typically work on the theoretical side of computer systems instead of the hardware side on which computer engineers mainly focus (although there is overlap). 

The Irish are an ethnic group and nation native to the island of Ireland, who share a common history and culture. Ireland has been inhabited for about 33,000 years, according to archaeological studies. For most of Ireland's recorded history, the Irish have been primarily a Gaelic people.

The Irish are an ethnic group and nation native to the island of Ireland, who share a common history and culture. Ireland has been inhabited for about 33,000 years, according to archaeological studies. For most of Ireland's recorded history, the Irish have been primarily a Gaelic people.