![]() ![]() JWST’s position in space means it’s far beyond the radiation emitted by Earth, but it still has to contend with heat from the sun. “An observation that would take an hour in space would take thousands of hours from a ground-based telescope.” But we’re fighting against this tremendously bright background,” Meyer said. Similarly, at the wavelengths that we’re talking about, everything on planet Earth glows. It’s really hard to see the star against the glare of the parking lights. ![]() “Imagine you want to see a star and you’re standing in a parking lot with lots of lights shining down. ![]() Ground-based telescopes fight against this source of noise to make observations. But it will be far more powerful than the current space-based instruments, and ground-based infrared telescopes have particular challenges: primarily, almost everything on Earth, including Earth, glows. JWST is not the world’s first infrared telescope-even in space. “This is going to be more than four weeks of terror.” Seeing unseen stars “If you remember the Mars Perseverance Rover, it was called the ‘Seven Minutes of Terror’ as they released the rover and sent it down to the planet,” Meyer said. The telescope’s tennis-court-sized sun shade, which will reduce radiation from the sun by a factor of a million, will also have slowly opened-all over the course of weeks, with the potential for something to go wrong at every step. By the time it has reached this position, its 6.5-meter mirror composed of ultra lightweight beryllium will have slowly unfurled. There, in a position called a Lagrange point, the telescope will orbit the sun in lockstep with the Earth. 24, the telescope, which will be launched on an Ariane 5 rocket from French Guiana, will travel one million miles from Earth-Hubble sits about 354 miles from Earth-and nearly 240,000 miles beyond the moon. When light is stretched enough, it shifts from visible light into the infrared.Īt Europe’s Spaceport in French Guiana, the James Webb Space Telescope will soon be encapsulated inside this 17 meter-high, 5.4-meter diameter fairing, which will provide protection from the thermal, acoustic and aerodynamic stresses during the ascent to space. ![]() This is because the earliest born celestial bodies and galaxies reside at extremely great distances from us, and as the universe expands, the wavelength of light from its outer reaches becomes stretched to longer wavelengths-similar to how the pitch of an ambulance’s siren changes as it moves away from you. And because discovering the first galaxies was a key scientific question-and still is today-it was clear this telescope would need to be an infrared telescope,” said Meyer, a professor in the U-M Department of Astronomy. “In 1997, there had been a series of high-level panel reports about how important it would be to plan for after Hubble. JWST will complement Hubble, which primarily uses visible light to make observations, but, at 30 years old, is also nearing the end of its life. The $10 billion instrument is a large, infrared telescope, a kind of telescope that captures different types of infrared light-light much redder than the reddest thing the human eye can see-on the nonvisible electromagnetic spectrum. Now, nearly 25 years later, Meyer and the astronomy community are on the cusp of JWST’s launch. As a postdoctoral researcher in 1997, Meyer began working on a committee tasked with dreaming up cutting-edge scientific applications of what was then called the Next Generation Space Telescope. It’s a launch University of Michigan astronomer Michael Meyer has been waiting for his entire career. ![]()
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