The “James-Webb” space telescope, a record-breaking machine, launched by an Ariane rocket on December 25, arrived at its destination on Monday after a first stage. But the telescope will not yet begin its observations, it still has a lot of preparation work to do.
We had to fire the engines one last time, and that’s the end of a journey of a million and a half kilometers covered in a month. the space telescope James Webb arrived at destination on Monday 24 January. It orbits around L2, the Lagrange point 2.
Lagrange points are places of gravitational equilibrium. Just park there to stay on a stable trajectory. There are five in the Earth-Sun relationship. The second is in the alignment of our star and our planet.
Mirror settings
If L2 was chosen, it is precisely for this reason. At this location, the Sun and the Earth will always be in the back of the telescope. Well protected behind its huge sun visor, its instruments will therefore benefit from perpetual shade, necessary for their proper functioning since they must be cooled to temperatures between -240 and -266 degrees.
Even if Webb has arrived safely, we will still have to wait before his first observations. The coming weeks and months will be devoted to final adjustments to the mirror. The telescope will fix a star to focus and avoid blurry images. It is thus only in June that his first snapshot will be made public.
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