Star birth in the early universe
Star birth in the early universe, artwork. This 1- billion-year-old universe is based on deep field observations by the Hubble Space Telescope. Deep field observations reveal the remotest objects in the universe. Because light has taken billions of years to reach Earth from these distances, these observations look back to the early history of the universe. Observations from 1995 and 1998 showed intense knots of bright blue-white stars, thought to be part of these primordial starburst galaxies that are too faint to be seen. The next generation of space telescopes will look further back in time to try and reveal this epoch of star formation.
© Nasa/Esa/Stsci/R.schaller/Science Photo Library
Big Bang and galaxies, artwork
Big Bang and galaxies. Artwork showing the galaxies that formed following the Big Bang (centre), the initial expansion of all the matter in the universe from an infinitely compact state some 13.7 billion years ago. The initial conditions are not known, but less than a second after the universe formed temperatures were trillions of degrees Celsius and the primordial universe was much smaller than an atom. As expansion occurred, matter formed and coalesced into the galaxies (around 500 million years later). The continuing recession of the galaxies from each other is a key piece of evidence for the Big Bang theory.
© VICTOR DE SCHWANBERG/SCIENCE PHOTO LIBRARY
Formation of the solar system
Formation of the solar system. Artwork showing the different sizes of objects (right-hand column) in the solar system at different stages (left-hand column) during its formation. Some 5 billion years ago (top), the primordial solar nebula, a cloud of gas and dust particles began to gravitationally accrete to form larger particles that orbited the newly formed Sun. The particles sizes, from top, are: 0.0001 millimetres; 0.001 millimetres; 0.01 millimetres; 50 kilometres (protoplanets); and 10, 000 kilometres (planet-sized objects). The Earth formed about 4.5 billion years ago. The composition of the particles varied, from icy particles (top) to rocky planets with metallic cores (bottom).
© GARY HINCKS/SCIENCE PHOTO LIBRARY