Artist’s impression of the James Webb Space Telescope as seen in space. Credit: ESA/ATG medialab After six months of testing and testing, NASA’s James Webb Space Telescope is finally ready to open a new window on the universe, capturing the faint light of the first stars and galaxies, probing the mysteries of black holes and studying the atmospheres of alien worlds. On Tuesday, NASA will unveil the first color images from the $10 billion observatory, pictures expected to rival or surpass the first spectacular images from the refurbished Hubble Space Telescope nearly three decades ago. “We’re going to give humanity a new view of the universe, and it’s a view we’ve never seen before,” NASA Administrator Bill Nelson told reporters during a media preview. “One of these images… is the deepest image of our universe ever taken. And we’re just beginning to understand what Webb can and will do.” Hubble has become one of the most iconic instruments in astronomical history, helping astronomers pinpoint the age of the universe, confirming the presence of supermassive black holes, capturing the deepest views of the universe ever collected, and providing images of the class of planets in our solar system. Earth. But Webb, operating just a few degrees above absolute zero behind a tennis-court-sized sunshade, promises to push the limits of human knowledge even deeper with a 21.3-foot-wide segmented primary mirror capable of detecting the faint, stretched infrared light from the first generation of stars to light up after the Big Bang. Launched on Christmas Day, Webb is in a gravitationally stable orbit nearly a million miles from Earth. Over the past six months, engineers and scientists have been working through a complex series of deployments, activations and checks, fine-tuning the telescope’s focus and optimizing the performance of its four science instruments. This image of the Carina Nebula, one of the James Webb Space Telescope’s first observation targets, was taken with the Hubble Space Telescope’s Wide Field Camera 3 instrument in 2010. Credit: NASA, ESA, Mario Livio (STScI), Hubble 20th Anniversary Team (STScI) The images released Tuesday, selected by an international team of astronomers, will “show the world that Webb is actually ready for science and that it is producing excellent and spectacular results,” said Webb Space Program scientist Klaus Pontoppidan. Telescope Science Institute. “And it’s also to emphasize the breadth, the sheer breadth of science that can be done with Webb and to emphasize all four science instruments,” he added. “And last but not least, to celebrate the start of normal science operations.” Targets for Webb’s first public images include: –The Carina Nebula: A vast star-forming region in the constellation Carina about 7,600 light-years from Earth that is four times the size of the Orion Nebula. The Carina Nebula is home to the brightest known star in our Galaxy as well as the Eta Carinae binary system, which includes a massive sun that is expected to explode in a supernova explosion in the near future (astronomically speaking). – Southern Ring Nebula: An expanding cloud of gas half a light-year in diameter ejected from a dying star. Relatively low-mass stars like Earth’s sun will end their lives by blowing away their outer layers, forming so-called “planetary nebulae” while their cores shrink and cool slowly. –Stephen’s Quintet: A collection of five galaxies in the constellation Pegasus, 290 million light-years from Earth discovered in 1877, the first such group of galaxies to be detected nearby. Four of the five galaxies are gravitationally interacting in a slow-motion merger. –WASP-96b: An unusual cloudless exoplanet 1,150 light-years away that is about half the size of Jupiter, orbiting its sun every 3.4 days. By spectroscopically analyzing the light from the parent star as it passes through the exoplanet’s atmosphere on its way to Earth, astronomers can reveal details about its chemical composition. –SMACS J0723.3-7327: The combined gravity of countless stars in massive galaxy clusters like this one can be a powerful lens if the alignment is right, magnifying light from more distant objects into the distant background to provide a deeper look back into space and time than would otherwise be possible. The Stephano Quintet, a group of five galaxies in the constellation Pegasus. Four of the galaxies interact gravitationally. Credit: NASA, ESA and the Hubble SM4 ERO team “The first images will include observations that cover the breadth of Webb’s science topics,” Pontoppidan said. “From the early universe, the deepest infrared view of the Universe to date. We will also see an example of how galaxies interact and grow, and how these cataclysmic collisions between galaxies drive the star formation process. “We will look at some examples of the life cycle of stars, starting with the birth of stars, where Webb can reveal new, young stars emerging from their natal cloud of gas and dust, to the death of stars, as a dying star sows the galaxy with new elements and new dust that may one day become part of new planetary systems.” Last but not least, he said, the team will demonstrate the first chemical fingerprints from an exoplanet’s atmosphere. One of the Hubble Space Telescope’s most stunning images was its initial “deep-field” look at a tiny patch of seemingly empty sky over a 10-day period in 1995. To the surprise of professionals and the public alike, this long-exposure image revealed more than 3,000 galaxies of all shapes, sizes and ages, some of them the oldest, most distant ever seen. Hubble’s subsequent deep fields pushed even further back in time, detecting the faint light of galaxies that shone within about 500 million years of the Big Bang. How stars formed and organized so quickly into galactic structures is still a mystery, as is the growth of supermassive black holes at their cores. Webb’s four instruments are expected to push the limits even closer to the beginning of galaxy formation. A test image from the telescope’s Canadian-made Fine Guidance Sensor, which was not optimized for detecting extremely faint objects, nevertheless revealed thousands of galaxies. Webb’s look at SMACS 0723 is expected to demonstrate the observatory’s massive reach. “This is really just the beginning, we’re just scratching the surface,” Pontoppidan said. “We have in the first images, observations of a few days. Looking ahead, we have many years of observation, so we can only imagine what that will be.”
