Name: NASA's James Webb Telescope Launch Is About to Make History
Uploaded: 2021-12-03T17:41:38.000Z
Duration: 4 min 57 s
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It’s taken over two decades, thousands of  international scientists, and billions of  

dollars to get to this monumental moment. The  James Webb Space Telescope is finally ready  

for launch and could revolutionize  our understanding of the universe. 

-I've been working on this project for 11  years. I have feelings of anticipation,  

worry. And also relief that we finally get to  do what we've been practicing for years to do.  

It feels unreal. Like, it's not really happening. 

-Oh, it’s real. And it should be launching  in a matter of days...hopefully. 

-You have to build something as big as Webb to  really get that capability to address some of  

these most fundamental questions we have. Questions like…what did the first galaxies  

look like? How do stars and planets  form? What are the key ingredients  

needed to support life on another planet? Webb has been in the works since the mid-90s,  

and today is an international collaboration  between NASA, the European Space Agency,  

the Canadian Space Agency, and many other academic  and industry partners. When it was first proposed,  

the telescope had one major goal: peer back  13.5 billion years to see the first galaxies. 

Light from those far-off galaxies has been  stretched through our ever-expanding universe.  

By the time it reaches Webb’s mirrors, it’s  stretched out of our visible light spectrum  

into the infrared region, so this is why  Webb was designed to see infrared light. 

-Since then, the mission has broadened  significantly scientifically, we now have  

four science themes. The first galaxies,  galaxy evolution, the stellar life cycle,  

and other worlds. -That's a lot to tackle, so  

how exactly is Webb going to do all this? -So, the James Webb Space Telescope will  

achieve these goals by two things. First,  by being large, and second, by being cold. 

-So let’s start there. If you haven’t noticed, Webb  has a massive, eye-catching gold mirror. It’s made  

up of 18 smaller segments that will click into  place after deployment and create a total surface  

area 6.5 meters across. For comparison, Hubble’s  primary mirror is only 2.4 meters in diameter. 

able to collect a lot of light, the more light  you can collect fainter objects you can see. 

And remember the temperature of Webb is also key,  the telescope has to be kept really really cold.  

That’s because if a telescope is warm,  it can emit its own infrared wavelengths  

and disrupt observations. So to keep  Webb at a chilly 50 Kelvin engineers  

designed a tennis court-sized sunshield  to block out light and heat from the Sun,  

Earth, and moon. To do this, the shield is made  up of five layers, which insulate the telescope  

while allowing heat to escape between each layer. Then there’s the infrared instruments themselves,  

which allow the telescope to do two  things: observe objects that emit longer,  

redder wavelengths (like the earliest galaxies)  and cut through the cosmic dust to see the nebula  

where stars and planets are forming. Using all  this new and improved tech, Webb will be able  

to show us things we’ve never even seen before. -When you launch the telescope, it does all its  

science, it sends all this beautiful,  enormous amounts of science data back,  

that you can do so many things. I  mean, the amount of information that  

will be there is absolutely astounding. -So after countless hours of hard work,  

set backs, and dedication, the James Webb  Space Telescope is finally ready for liftoff. 

The telescope will blast off from ESA's spaceport in  Kourou, French Guiana. The observatory will launch  

on the reliable Ariane 5 rocket, which is built  to carry heavy payloads. Still, Webb’s mirror  

will be folded to fit into the payload fairing. After lift-off, Webb will spend about 30 days  

travelling to the second Lagrange point, where  the Webb telescope can comfortably stay on course  

with the Earth as it travels around the Sun. -Watch the launch then follow us for for about  

six months as we get everything ready.  And please have patience during this time.  

It is really necessary to take six  months to get everything cold enough,

before you you get to see all the beautiful  images that that we've all been waiting for. 

-And hopefully, we’ll be  surprised by what Webb discovers. 

-We can plan all day long the science that we're  going to do but potentially the most exciting  

Just about as long as Webb has been in  production, we’ve been covering it...or  

at least that's what it feels like. Take a look  at the experts we’ve interviewed over  

the years if you want to know about how  James Webb got to this exciting moment.  

Don’t forget to subscribe to Seeker. Thanks  for watching and I’ll see you next time.

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NASA's James Webb Telescope Launch Is About to Make History

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