How the Golden Eye of the James Webb Space Telescope Will See the Edge of the Universe

[Music] this is the golden eye of the james webb space telescope unparalleled in scope and scale webb is the largest telescope to ever launch into space it's a little bit like our generations apollo in that it was very challenging to build but the payoff is also very large i mean this is about as powerful as it gets this is an extremely ambitious project we developed all these new technologies that didn't even exist but we needed it to carry out the science an international project like this that has countless firsts takes time but the painstaking effort to design construct and test webb's optical system will be worth the wait overnight the eye of the telescope will revolutionize our understanding of the cosmos and be set loose on the biggest questions in astronomy well i've been working on the james webb space telescope for 20 years and when i first started you know we really didn't even know exactly what the design would look like what materials we would make the mirrors out of how many segments the telescope would be we actually had to invent multiple technologies that's because the astronomical community was after something that had never been observed before the early universe the first stars and galaxies started to form 100 to 250 million years after the big bang around 13.6 billion years ago because the universe is expanding the visible light from the early universe gets stretched into the infrared and that's called a cosmological redshift it's this cosmological redshift that webb's optics will be hunting for to uncover the story of the early universe infrared light can pass through dust in the universe and so it allows us to peer through dust clouds and see for example stellar nurseries no other telescope today has the collecting power and sensitivity that nasa's jwst has to lift the veil on the universe's secrets the james webb space telescope is sensitive enough that if there were a bumblebee at the distance of the moon we would be able to detect it the telescope's core superpowers come from its advanced optical system james webb's eye otherwise known as the optical telescope element consists of four ultra-reflective golden mirrors and dozens of sub-systems to support the massive optics the first thing you recognize is the gold mirrors there's a reason why we chose gold is because it has a very high reflectivity in the infrared out of the four mirrors it's the primary one that really stands out that's the first mirror that light hits and in this case we have 18 segments they're hexagonal shaped which means each mirror actually acts as a separate telescope until they're aligned in space to work as one all of the 18 hexagonal segments and additional mirrors are made of beryllium a strong and lightweight metal that holds its shape at cryogenic temperatures remember space is a balmy negative 270 degrees celsius the other subtlety of it all is because it's infrared the mirrors have to be cooled to very cold temperatures so that they don't produce heat in the form of infrared light that would contaminate the images and lastly a large telescope gives you resolution the resolution goes with the diameter of the primary mirror webb's primary mirror is 6.5 meters in diameter which gives the telescope more than six times the collecting area of the hubble space telescope it's a lot like collecting raindrops and the bigger the bucket the more raindrops you collect and when you're trying to see the very early universe which is very dim you need to collect a lot of photons for the engineering team it's easier to look back at what was achieved when you're at the finish line so many aspects of the telescope needed to be invented before manufacturing began years ago from the segmented beryllium mirrors to the large sun shield for keeping the system cold to algorithms lots and lots of brand new algorithms for keeping the mirrors aligned 1.5 million kilometers away in terms of you know a science mission like this this is the largest most ambitious one that nasa has ever taken on and it's arguably one of the most complicated but also powerful ones that's because to see the universe like never before it requires a new type of observatory for the jwst team building that observatory meant constructing a complex cascade of mirrors that can focus light down like no other telescope before it the first mirror is the primary mirror that's what initially collects the light from the distant universe the light then converges down to a secondary mirror and the secondary mirror continues to focus the light and then that reflects light to what we call the tertiary mirror and then finally the light is sent to a fourth mirror which is the fine steering wheel and the purpose of that mirror really is to correct slow drifts between the telescope and the spacecraft after all that an image is created as the light enters the four science instruments we call them science instruments but you can think of them as cameras they each have their own detector which actually collects the light like the detector on your camera the light photons get converted into electrons they get recorded onto a data recorder on the telescope and then data actually gets sent back down to the earth using the deep space network and once we have the first completed images the long wait will have ended so space telescopes are like time machines in a sense they can take us back and collect these photons that were created at the very beginning of the universe that light is always there it's always coming down we just haven't had the capability until now in the first year of operations webb's mirrors will collect light from early galaxies and stars the environment around black holes supernovae and other space phenomena with greater sensitivity than ever before and of all the highly anticipated observations one is a personal favorite for michael i'm really excited about the exoplanet discoveries we know of over four 000 exoplanets orbiting other stars we don't really have an understanding of what their compositions are and that's one of the key aspects of the web mission the first time we'll really get a good understanding of their properties and those are very fundamental features for understanding how they formed how they evolved and also will give us some insight as to the habitability of these exoplanets whether there might be liquid water where life should exist by searching for the building blocks of life elsewhere it can give us insight into how life began on our own pale blue dot web science mission touches on so many fundamental questions in cosmology that it holds the promise of rewriting and expanding our textbooks for years to come so every time we have a transformative increase in observing capability like web there's just tremendous scientific discovery you know we used to use the phrase early when we were developing public expect the unexpected and i think here you can almost say expect the unexpected square the jam flip space telescope is a new kind of telescope it's never been done before this is really new terrain for nasa and for the world and setting a stage for future telescopes that are scalable to larger sizes which means if we ever want to see a pale blue dot around another star the foundation has been set [Music] you

Channel: Seeker

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Keywords: focal point, seeker, documentary, interview, short doc, science news, explainer, technology, tech, seeker documentary, full documentary, NASA, James Webb Space Telescope, JWST, James Webb, space telescope, telescope, Optical Telescope Element, big bang, early universe, black holes, exoplanets, trappist-1, beryllium, galaxy, alien life, infrared light, planet, universe, space, astrophysics, cosmos, cosmology, astronomy, time machine, golden eye, forefront, new frontier, science, scientists, discovery

Id: st-iyZsgpic

Length: 7min 47sec (467 seconds)

Published: Sun Dec 19 2021