Long awaited by scientists, the launch of the orbital observatory had already had to be postponed for a few days, from December 18 to 22, after an incident during the preparations for take-off which had required additional tests.
This time, the mission teams must resolve a communication problem between the observatory and the launch vehicle. A new launch date is expected to be announced no later than December 17.
The result of a collaboration between NASA, the European Space Agency and the Canadian Space Agency, Webb was placed on top of the rocket on Saturday, December 11. This is when the malfunction was detected.
The largest and most powerful orbital observatory to ever launch into space, will take off aboard an Ariane 5 rocket from the European spaceport in Kourou, French Guiana.
The assembly process was carried out in a strict framework of cleanliness. It was one of the most delicate stages of the launch of the 6,200 kg telescope which must explore with unparalleled precision all the phases of the cosmos, up to the first ages of the Universe and the formation of the first galaxies.
The telescope will be placed in orbit around the Sun, 1.5 million kilometers from Earth, well beyond the limits of its big brother Hubble, which has been operating at an altitude of 590 km since 1990.