On November 30, 1609, Galileo turned his telescope towards the night sky. This singular act revolutionised astronomy. Until then, scholars held that celestial objects were without any kind of blemish. Galileo showed that the Moon had craters and mountains. All celestial objects, including stars, were thought to go around the Earth. The telescope, by observing phases of Venus firmly established that planets go around the Sun and not the Earth. The Milky Way, a haze in the dark night teemed with hundreds of stars, established that the cosmos is immense and beyond our imagination. Galileo revolutionised astronomy using a crude telescope which by today's standards is merely a toy.
The first five images released by NASA (National Aeronautics and Space Administration) on July 11, captured by the James Webb Space Telescope (JWST) is no less momentous in the history of astronomy than the day Galileo turned his telescope toward the heavens.
The deep field image of the SMACS 0723 cluster of galaxies has images that date back to times when the first stars were born. The images from Carina Nebula vividly show the birth of new stars. In contrast, the Southern Ring Nebula image details a dying star. In Stephan's quintet, the JWST has captured the cataclysmic cosmic collision of galaxies. By analysing the spectrum of the radiation from WASP-96 b, an exoplanet (a planet orbiting a distant star), the telescope has shown conclusively the presence of water vapour in the atmosphere of this hot, puffy gas giant planet orbiting a distant Sun-like star. With its sharp vision, more light-collecting area and ability to see in the invisible infrared regions, the JWST is sure to expand our understanding of the cosmos.
