Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry to explain their origin and their overall evolutio
Megaliths from Nabta Playa, constructed by Neolithic populations, located in Aswan, Upper Egypt.
The Nebra sky disc found on Mittenberg hill in Germany and dated to c. 1800–1600 BCE.
A Babylonian planisphere (7th century BCE) was an early astronomical instrument. Its use of sexagesimals (e.g. 12, 24, 60, 360) is still being used today through having been broadly adopted for timekeeping and astrometry.
Portrait of Alfraganus in the Compilatio astronomica, 1493. Islamic astronomers collected and translated Indian, Persian and Greek texts, adding their own work.
The universe comprises all of existence: all forms of matter and energy, and the structures they form, from sub-atomic particles to entire galactic filaments. Since the early 20th century, the field o
The Hubble Ultra-Deep Field image shows some of the most remote galaxies visible to present technology (diagonal is ~1/10 apparent Moon diameter)
The three possible options for the shape of the universe
The formation of clusters and large-scale filaments in the cold dark matter model with dark energy. The frames show the evolution of structures in a 43 million parsecs (or 140 million light-years) box from redshift of 30 to the present epoch (upper left z=30 to lower right z=0).
3rd century BCE calculations by Aristarchus on the relative sizes of, from left to right, the Sun, Earth, and Moon, from a 10th-century AD Greek copy