The James Webb Space Telescope has now unfolded its sophisticated mirror system. Find out why its program manager called this “a remarkable feat for our team, NASA, and the world.”
These days, we tend to think that stargazing and telescopes are inseparable. Of course, that wasn’t always the case.
The earliest astronomers used nothing but their own two eyes. Yet they made remarkable discoveries by using their ingenuity and powers of observation. Likewise, amateur stargazers can still learn a lot about the Universe by just taking in the night sky with no gear at all, provided they have a good teacher.
Galileo didn’t invent the telescope, but, as far as we know, he was the first person to aim one at the night sky to study the heavens. Seeing the rings of Saturn, the moons of Jupiter, and the phases of Venus helped him to realize that Copernicus was right. The Sun is at the centre of the solar system, and the planets, including Earth, revolve around it.
Newton Improved Telescope Design Using Mirrors
Isaac Newton improved the telescope’s design by using mirrors instead of lenses. In his design, the light from the stars is reflected and focused using a parabolic mirror at the back of the tube, providing more light-gathering power.
The trouble with telescopes of any kind has always been looking through the atmosphere. The air around us is dynamic, which causes optical distortions, affecting what astronomers call the “seeing.”
The Orbiting Solar Observatory was Humanity’s first attempt to get around this age-old limitation. It was launched into space between 1962 and 1975 and consisted of a series of X-Ray telescopes mainly meant to study the Sun.
Most Famous Orbital Spyglass is the Hubble Telescope
The most famous orbital spyglass of them all is the Hubble Space Telescope. Launched in 1990, it got off to a rocky start because of what people came to call the “Hubble Trouble.”
The Hubble uses Newton’s design principle. The problem was that technicians ground the 2.4-metre mirror incorrectly. So astronauts installed a set of corrective lenses on it in 1993, after which it was flawless.
Sadly, the Hubble Space Telescope’s mission is drawing to a close. Its equipment is starting to fail, and its orbit is slowly decaying.
James Webb Space Telescope Launched on Christmas Day
Its replacement is called the James Webb Space Telescope. Launched on Christmas Day, its flagship mission is to look back in time for the light from the first galaxies in the early Universe.
It will also be exploring our solar system and exoplanets, planets orbiting other stars in our galaxy. It’s a joint project of NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA).
Yesterday, we learned that the Webb Telescope successfully deployed its 6.4-metre gold-plated primary mirror. This is the broadest diameter telescope mirror ever launched into space.
Largest Telescope Mirror Ever Launched into Space
The mirror consists of two wings, which the Webb team had folded up into the nose cone of an Ariane 5 rocket for launch. Once they had deployed several other critical systems, the team was ready to unfold the mirror consisting of 18 hexagonal segments.
This complex and delicate procedure took two days to complete. The Webb Telescope unfurled its first wing on January 7, and the second wing released on January 8. With both wings latched into position, the team has completed all major launch deployments.
Gregory L. Robinson is NASA’s program director for the James Webb Space Telescope. He expressed these thoughts once the team had completed the deployment.
“Remarkable Feat for Our Team, NASA, and the World”
“The successful completion of all of the Webb Space Telescope’s deployments is historic. This is the first time a NASA-led mission has ever attempted to complete a complex sequence to unfold an observatory in space — a remarkable feat for our team, NASA, and the world.”
The Webb Telescope is the largest and most complex space science telescope in history. It will explore every phase of cosmic history – from within our solar system to the most distant observable galaxies in our Universe.
Because the speed of light is constant, looking out into space is also looking back into time. That’s how the Webb Telescope will be able to look back 13.5 billion years and observe the Universe’s earliest galaxies, offering new explanations for how our cosmos began.
Look Back 13.5 Billion Years and Observe Earliest Galaxies
The next step is to align the telescope’s sophisticated optics. Those 18 hexagonal segments have 128 actuators on their reverse sides.
The ground team will use those actuators to flex each mirror and bring them into overall alignment to create one focused primary mirror. This will take a few months to complete.
Also, the Webb Telescope needs to change course to move into its final orbital position. This will be almost a million miles from Earth.
Everyone Loves a Hero’s Journey Story
Projects like the James Webb Space Telescope are vital to Humanity for at least two reasons. The first is that everyone loves a hero’s journey story.
Lately, our space exploration heroes tend to be machines like the Mars Rovers or our space telescopes. But, of course, we need to remember that heroic people here on Earth design and deploy all of those machines and make their journeys possible.
The other value the Webb will deliver is that Humanity needs a new story. We’ve always told each other meaningful stories that explain how the world began and our place within it.
Unearthing New, Factual, Meaningful Story
Modern science has made most of those stories obsolete. Even so, it’s been a fair exchange. We’re now unearthing a new, factual tale that promises to be even more meaningful than any of our traditional myths.
Thomas Zurburchen, the associate administrator for NASA’s Science Mission Directorate, summed it up this way. “Webb’s successful deployment exemplifies the best of what NASA has to offer: the willingness to attempt bold and challenging things in the name of discoveries still unknown.”
We always have more to learn if we dare to know.
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