![]() Rather, it is positioned 1.6 million km (one million mi.) from the planet, where it station-keeps in what’s known as a Lagrange point-a spot in space where the gravity of the Earth and the sun cancel each other out, allowing objects to circle around the invisible point as if they were orbiting a solid body like a planet. It also does not orbit the Earth, where the constant day-night cycle of every orbit would cause its own disruptive temperature changes. The mirror remains exposed to space, since placing it in a housing like Hubble’s main mirror would trap heat. ![]() The Webb’s main mirror measures 6.5 m (21.6 ft.) across, and is made of 18 hexagonal segments, each of which can be adjusted in seven different axes with a precision down to the nanometer-or a billionth of a meter-allowing the overall mirror to be focused for maximum detail and clarity. That makes for some unusual architecture. For that reason, the telescope must be kept ultra cold. In order to work, then, Webb needs to be protected from stray heat, which would blur its infrared optics just as stray light would blur Hubble’s visible-spectrum mirrors. Infrared light cuts right through that interference. The disks are tilted face-on to Earth and so give astronomers a bird's-eye view of what's happening around the star. Hubble could never see the 13.6 billion light years distant that Webb can, because visible light from so far away is obscured by dust and gas in deep space. Release Date Caption Comparison images from the Hubble Space Telescope, taken several years apart, have uncovered two eerie shadows moving counterclockwise across a gas-and-dust disk encircling the young star TW Hydrae. The Webb telescope operates instead in the infrared spectrum, a wavelength of light beyond the visible spectrum that is a measure more of heat than of light. Until now, exoplanets, or planets circling other stars, were detectable in only one of two ways: The transit method, in which astronomers discern the small dimming of light in a parent star as an orbiting planet passes in front of it and the radial velocity method-in which they look for the small wobble in the position of the star as the gravity of the orbiting planet tugs on it. Hubble is looking at the Galaxy NGC-3783 with Wide Field Camera 3 (WFC3/UVI) for Prof. Still, it was in some ways, the smallest object the telescope imaged-the exoplanet WASP-96b-that will likely cause the greatest excitement. Read More: These 5 Photos From the James Webb Space Telescope Are Mind-Blowing. We’re made of the same stuff that in this beautiful landscape.” We humans really are connected to the universe. It just reminds me that our sun and our planets, and ultimately us, were formed out of the same kind of stuff that we see here. “You know, every light we see here is an individual star, not unlike our sun, and many of these likely also have planets. ![]() “I can’t help but think about scale,” said deputy project manager Amber Straughn, as she showed off the Carina image.
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