* Early Astronomers: Many cultures, including the Babylonians, Egyptians, and Chinese, developed systems for observing and cataloging stars. However, these systems were often based on naked-eye observations and less rigorous than modern mappings.

* Hipparchus (2nd century BC): Hipparchus is often credited with the first systematic star catalog. He measured the positions of about 850 stars and established a system for measuring their brightness.

* Tycho Brahe (16th century): Brahe was a Danish astronomer known for his precise naked-eye observations of the stars and planets. He compiled a detailed star catalog containing over 777 stars, which was later used by Johannes Kepler to develop his laws of planetary motion.

* Modern Telescopes: The invention of the telescope revolutionized astronomy and enabled much more precise mapping. Over time, many astronomers have contributed to mapping the sky, including:

* William Herschel (18th century): He conducted systematic surveys of the Milky Way, discovering thousands of new stars and nebulae.

* John Herschel (19th century): He continued his father's work, producing a catalog of nearly 2400 nebulae.

* The Harvard College Observatory (19th and 20th centuries): This observatory played a significant role in mapping the sky, particularly in the field of stellar classification.

* Space-based Telescopes: The launch of space telescopes like the Hubble Space Telescope has allowed us to map the sky with unparalleled detail and precision.

So, while Hipparchus may be considered the first to systematically map the sky, many other astronomers and projects have made significant contributions throughout history.