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James Webb Telescope captures thousands of galaxies in first photo The first image released by NASA from the James Webb Telescope shows thousands of galaxies, including the faintest objects ever observed. From cosmic cliffs to the birthplace of stars, the James Webb Space telescope is stunning stargazers and non-stargazers alike with its breathtaking views of a universe never glimpsed before. The world's largest and most powerful space telescope is capturing images of thousands of galaxies – some of which formed billions of years ago after the Big Bang – and some of the faintest objects ever observed. The telescope will explore every phase of cosmic history, NASA says. Here's what you should know: What do the images show?The first pictures from the telescope, released Monday and Tuesday, show thousands of galaxies, some of which formed nearly 13.2 billion years ago. They are seen in part because the James Webb Telescope targeted a cluster called SMACS 0723, which has a gravitational field so strong it magnifies the light of older, more distant galaxies. NASA also plans to release imagery of a “stellar nursery” where the Carina Nebula, the Southern Ring Nebula and Stephan’s Quintet formed. See first images: What the James Webb Space Telescope has captured Where is the James Webb Telescope now?The Webb telescope is pretty far away – 1 million miles from Earth to be exact. It launched in December 2021 from French Guiana. What is the James Webb Telescope?The James Webb Space Telescope was built through an international partnership between the Canadian, European and American space agencies. It has been in development since the 1990s and, according to NASA, aims to explore cosmic history, taking a deeper look at our own galaxy and the many that came before it. Read more NASA News: NASA 'strongly rebukes' pro-Russian separatist flag display on International Space Station How does the telescope look back in time?The telescope looks back in time using gravitational lensing. The latest image from the Webb telescope looks much bigger than it is: The picture is about the size of a grain of sand held at arm’s length and shows only an infinitesimally small bit of our vast universe, NASA says. But the galaxy cluster captured in the image, known as SMACS 0723, serves as a gravitational lens, bringing to light more distant galaxies. Its gravity is so strong that it distorts the light coming from other galaxies, making them appear brighter and therefore visible to us. How long will the James Webb telescope last?The Webb facility is expected to operate for five years but is not capped at that, and it has the materials to operate for more than 10 years, according to NASA. Is James Webb much better than Hubble?The James Webb telescope is the most powerful space telescope in history. It is better in resolution and detail than its predecessor, the Hubble Telescope. It has a larger collecting area and can capture longer wavelengths in infrared. Both of these space photographers take “deep field” images, pictures with long exposure times (12½ hours in Webb's case) that allow even the most faint form of incoming light to be seen. The Hubble Telescope, which had its own dramatic reveal in the 1990s, is now second fiddle. The James Webb telescope is designed to capture light 100 times fainter than that captured by Hubble. Check out Hubble Telescope's discoveries: 'Needle-in-a-haystack' search finds possible phantom-like black hole roaming the Milky Way Can the James Webb Telescope see planets?Yes! New images show a distant gas giant planet. Evidence of water, clouds and haze gave scientists an unprecedented observation point for planets hundreds of light-years beyond Earth that would be habitable. As for the planets in our own solar system – the Webb telescope can see those too, of course. "Because it is so powerful, it has capabilities that we can apply everywhere in the cosmos, even in our local neighborhood, the solar system," said Heidi Hammel, an interdisciplinary scientist working on Webb, in an interview with Space.com. What is the temperature of the James Webb Space Telescope?The Mid-Infrared Instrument (MIRI)) employed by the telescope is cooled to below 7 kelvins, or minus 447 degrees Fahrenheit, according to NASA. Since the operation of the telescope produces heat, a cryocooler of gaseous helium is required to offset that and maintain temperature stability. Who funded the James Webb Telescope?The Webb telescope cost $10 billion. About $9.7 billion is from the U.S.; $810 million came from the European Space Agency; and $160 million came from the Canadian Space Agency. JWST isn't only funding recipient: Scientists are searching the universe for signs of alien civilizations: 'Now we know where to look' Who was the James Webb Telescope named after?The James Webb Telescope was named after James E. Webb, who was NASA's administrator from February 1961 to October 1968. NASA's website describes Webb as the government official who did more for science than perhaps any other and a fitting recipient to be the namesake of the Next Generation Space Telescope.
The James Webb Space Telescope (JWST) is the most advanced and most expensive telescope ever built. It has often been referred to as the 'successor' to the Hubble Space Telescope, which was launched in 1990. But how similar are they really? Find out how the James Webb Space Telescope and Hubble Space Telescope compare with astronomers from the Royal Observatory Greenwich, and get ready to see the very first images from JWST...
Light travels in a range of frequencies along the electromagnetic spectrum. Our eyes have evolved to detect the band of the spectrum which is known as ‘visible light’, which is unsurprising given that our atmosphere blocks out many of the other wavelengths. However, there are many other forms of light we cannot see, both inside and outside our atmosphere. Infrared light has a longer wavelength and can pass through objects in space that visible light is blocked by, such as gas and dust. This is why images taken using telescopes which detect infrared frequencies can pick out objects beyond these clouds, and appear clearer than those taken using other telescopes. So is the James Webb Space Telescope replacing the Hubble Space Telescope?Because JWST doesn't cover the same types of light that Hubble is capable of, it isn't truly 'replacing' the same capabilities that Hubble has. However, while we will lose out on the ability to see in ultraviolet light in the same way that Hubble did, by expanding the range of wavelengths out to infrared light, JWST will provide access to a part of the spectrum that Hubble never had.
Light plays a key part in us being able to understand more about about the Universe – but what actually is it? Join Royal Observatory Greenwich astronomers to find out. Find more videos like this
JWST will have a vast sunshield used to help keep the telescope cool. This is important for all space telescopes but is particularly true for infrared telescopes like JWST as 'warm' objects radiate lots of infrared light. If the telescope itself isn't kept cool, then the telescope risks blinding itself to the light of any object it is attempting to observe. The main improvement here though is the telescope aperture. This is effectively the size of the hole at the end of the telescope, or, in the case of telescopes like these, the size of the mirror that is used to collect the light. It's the equivalent of the pupil at the centre of our eye, the dark 'hole' that lets in light. The larger the aperture, the more light the telescope can gather in one go and so the fainter an object it can see. Hubble, with its 2.4 metre aperture, can see objects at least 60,000 times fainter than the human eye (which is then greatly extended by using cameras to take long exposure photographs). With a mirror almost three times wider, JWST will be able to see objects almost nine times fainter than Hubble, allowing us to peer even further into space.
Space-based telescopes have a huge advantage over ground-based ones. By being above the atmosphere they don't have to peer through the shifting air to see into deep space, granting them a clearer view than most ground-based telescopes can achieve. They are also unaffected by the weather, which can be a big problem for astronomers. However, being in space makes fixing things that go wrong considerably more difficult. Hubble famously had a small flaw in its mirror upon launch that required a mission into space to fix. JWST will have no such rescue. At 1.5 million kilometres away, far further than any human has ever travelled, if something goes wrong it won't be possible to head into space and fix it. It is being placed in such a remote place for several reasons. It keeps the telescope far from the reflected radiation of the Earth, one of many choices designed to keep this highly sensitive telescope cool. It will also be in a place where the gravity of the Sun and Earth work together, making it easier to keep the satellite in place. How far back in time can JWST see?The further away an object is, the further back in time we are looking. This is because of the time it takes light to travel from the object to us. With JWST's larger mirror, it will be able to see almost the whole way back to the beginning of the Universe, around 13.7 billion years ago. With its ability to view the Universe in longer wavelength infrared light, JWST will be capable of seeing some of the most distant galaxies in our Universe, certainly with more ease than than the visible/ultraviolet light view of Hubble. This is because light from distant objects is stretched out by the expansion of our Universe - an effect known as redshift - pushing the light out of the visible range and into infrared. Why has JWST been delayed so long?Space projects often take longer than expected, but JWST has been more unlucky than most. It was originally planned to be launched in 2007, but a major redesign, escalating costs and delays led to it being pushed back to around 2018. However, the testing period from 2016 onwards also suffered from long delays, and a further delay was imparted by the global pandemic of 2020. The telescope finally launched on Christmas Day 2021 at 12.20pm GMT (7.20am EST). Over the next six months, the telescope performed a series of complex deployment operations, including the unfurling of its huge sunshield. Watch the successful launch back via the NASA live stream below.
Launch date: 25 December 2021 Launch time: 12.20pm GMT (7.20am EST) Launch location: Europe's Spaceport, French Guiana
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What will the James Webb telescope see
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