A seemingly delicate bubble of gas photographed by the Hubble Space Telescope in 2006 captures the aftermath of a supernova in the Large Magellanic Cloud some 160,000 light years from Earth’s Milky Way. The remnants of the doomed star form a ring-like structure 23 light years across expanding through space at 18 million kilometres per hour (11 million mph). The remnant, known as SNR 0509, features ripples in the bubble’s surface that may be the result of density variations or collisions with debris from the original explosion. This image was captured by Hubble’s Advanced Camera for Surveys using a filter that isolates the glowing hydrogen in the expanding shell. Visible light images of the surrounding star field were taken by Hubble’s Wide Field Camera.
A study just published by University of Texas at Austin assistant professor Steven Finkelstein and colleagues reveals that galaxies were more efficient at making stars when the universe was younger. The announcement explains the team’s discovery that there are a lot more bright, highly star-forming galaxies in the early universe than scientists previously thought.
Astronomers using data from the NASA/ESA Hubble Space Telescope and other observatories have performed an accurate census of the number of galaxies in the universe. The researchers came to the surprising conclusion that the observable universe contains at least two trillion galaxies. The results also help solve an ancient astronomical paradox — why is the sky dark at night?