You can watch the launch broadcast on December 25, 2021 here: • En güçlü teleskop...
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December 25, 2021 made history as the beginning of the days when the definition of the universe will change! Because the world's most advanced telescope is
being sent into space. The James Webb Space Telescope, which is 100 times more powerful than the Hubble telescope, will let us to see things we have never seen before. It will observe the earliest times when the universe was born. Working like a time machine, it will enable us to learn things we never knew, about how galaxies, stars and planets were formed.
Let's review what we know about space in order to better understand how important this event is. Even on a clear night, when you look up, you can see up to 5000 stars with the naked eye. Until the 2000s, no human being on earth could see more than this.Because the small size of our eyes and the atmosphere of the earth limit our vision. That's why, in the 90s, a new eye 100 times the size of the
human eye was made and sent into space: Hubble. The famous telescope that recorded most of the amazing cosmic images we've ever seen.
Hubble can capture this image which covers an area as large as Moon in the sky. There are 200,000 galaxies even in such a small area. But what could be in the spaces
in between?
Curious about this, scientists did an experiment. On September 24, 2003, the Hubble space telescope covered a dark area for a total of 11 days. It successfully captured lights that are one ten-billionth fainter than the human eye can see, Even in a tiny space that seems to contain nothing, hundreds of thousands of galaxies... Each one containing hundreds of billions of stars.
This image, called "Hubble Deep Field," not only changed the books on astronomy, it also wiped out all our estimates of the size of the universe.
This is the difference
that emerges when looking at the universe, 500 km above the ground with a 2.4 meter diameter eye. which was previously only visible from Earth with a 2.5 cm diameter
human eye. So you know what is next? A much larger eye, some 6.5 meters in diameter, will be sent into outer space to a distance of 1.5 million kilometers away.
It's really difficult to seize the size of the James Webb Space Telescope. When people are near, you realize that the telescope mirror is the size of a basketball court
together with the shields. These shields are to protect it from the sun. And when I say shield, it merely consists of 5 layers whic are thick as paper. When it is up in space, the outermost layer will face a temperature of 110°C/230°F. Right In the area where the telescope is located 5 layers
below, the temperature will drop below -200°C/-392°F. Because it needs to work at a constant -267°C/512.6°F in order to capture the faintest lights and infrared waves
from the farthest points of the universe. Otherwise, it begins to detect its own signature, it is that delicate!
Do you know what -267°C/512.6°F means? That's slightly hotter than absolute zero! And the absolute zero is considered the very bottom of the thermodynamic scale, where the enthalpy and entropy of a substance's molecules reach their theoretical minimum value, and it is taken as −273.15°C/-523.67°F. In order for the instruments and cameras on the telescope to operate at such cold temperatures, they have designed a special cooling system that works on helium gas, which they call a "cryocooler".18 gold-plated hexagonal mirrors are arranged into a honeycomb shape, acting as a single mirror. Therefore, each mirror must be guided by very sensitive motors. The mirrors can move independently and with a precision of 1/10 of the thickness of human hair! This way the heat will be captured just like in night vision devices. Infrared light. Because that is what left from the galaxies from the beginning of the universe and time. And it is such a dim light that it requires looking at the same spot continuously for days and collecting it. Thus, it will not orbit the Earth, like Hubble did but will be sent to a special region four times farther than the Moon.
In my previous videos, I told you about some special areas, the Lagrangian points, that surround celestial bodies. The telescope will be positioned at 1.5 million km from the Earth in a special region called the L2 point for short which is formed by the Earth and the Sun. In this way, the light of the Earth and the Moon will not disturb it, because it will move in an orbit that always remains behind it and the Sun. But in order to reach that special region, it needs to be sent about 4 times further than the Moon! Looking at the beginning of a 14 billion-year-old story, the first page of the book, can illuminate this darkness. Not only will a telescope be sent into space in the coming days. An eye will be placed that can illuminate our past and who we are. And that day will go down in history as the day the universe changed as we know it.