Astrophysicist Eric Lagadek explains why these images are “extraordinary.”

5:00 pm, July 13, 2022

The first image of the James-Webb Telescope, the most powerful space telescope ever designed, has already orbited the Earth. These color shots, fully published by NASA on Tuesday, were eagerly awaited by the scientific community. Six months ago, the James-Webb telescope was launched into space via an Aryan 5 rocket from French Guiana. In the project from the 1990s, 20,000 people were required to participate in its implementation. Located 1.5 million kilometers from Earth, it should have enough fuel to work for twenty years. Astrophysicist Eric Lagadek, very active on the social network Twitter, did not fail to publicize this scientific fact. He sees this as a great step, which will allow us to better understand the universe.

Read more – James Webb Space Telescope will be back in time

What do these pictures tell us?
Here are five pictures that have been published. In the first, as Joe Biden showed during a press conference, we see galaxies forming right after the Big Bang. In addition to images, we have spectra, so we know what they are made of and how they were made 13 billion years ago. You have to imagine: in a tiny part of the sky, you can see a huge part of the universe.

What makes this image represent such an event?
We knew we were going to get this kind of picture, because it’s designed for this telescope, it’s not a surprise. We will be able to explore the universe with its infrared power. It is the largest telescope sent into space. As expected in these first pictures, they remain remarkable. What’s new is that the Hubble Space Telescope needs a few weeks to do it. Today, with the help of this national telescope, it is much faster and more precise. It’s taller, so it takes on light more quickly.

Read more – A first image of the James Webb Telescope has been unveiled

What does infrared bring?
First, you need to know that it is not new. The first infrared satellite was launched into space in the 1980s. There, however, the telescope is larger than ever. Infrared has different interests, but the main one is to go through the dust, which is not opaque to infrared. Also, distant galaxies have a light that tends to red. The problem is that sky observations are very difficult to manage from the ground up. Everything emits infrared, even our body temperature. Going above the atmosphere therefore allows the telescope to see more distant objects.

Why do we say it is a time machine?
In fact, if I look at you, I can see you in the recent past because light is spreading at a speed of more than 300,000 kilometers per second. If I could see anyone in New York, it would be a more distant past. When, from Earth, we look at Andromeda, we see what this galaxy was like millions of years ago. The problem is that for very distant objects, it needs to be managed in order to capture the light needed to see them. With James-Webb, the interesting thing is being able to observe objects that are in a different state today, or even that no longer exist.

Astronomy is wonderful, so it is a great entry into the scientific method

What can we expect in the years to come with such a telescope?
The goal is to better understand the structure of galaxies, exoplanets, and to see the first stars in the universe, as well as to follow the cycle of matter. We will be able to observe more precisely how they survive and die. This is a new way of exploring the universe. We could never observe some things.

When we see the media coverage of these images, the desire of Thomas Pesquet or even Elon Musk to go to Mars, can we talk about a new frenzy for space?
In recent years, astronomy has made many discoveries that allow us to dream. But we should not dream that we will go to another planet, so that we can save ourselves. On Twitter, I share the discoveries of astronomy and I see that it arouses some interest. It is important to see and understand. It’s not enough to just look at the photos shown by Joe Biden, you have to explain, that’s why I’m very present on Twitter. We are facing big scientific challenges: epidemics, climate crisis… even though we do not have enough scientific culture. Astronomy is amazing, so it’s a great entry into the scientific method.

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