After successfully completing its final tests, the James Webb Telescope is being prepared for shipment to its launch site in Guyana, where it will be launched into space aboard an Arianne 5 rocket.
In the papers since the 90s, the James Webb Telescope was supposed to cost less than a billion dollars and be ready by 2010. Thirty years and almost ten billion dollars spent later, the observatory is finally ready for its launch, except for a few details. We take stock of the next deadlines.
Last test campaign completed
A few days ago, the engineering teams concluded the program of “long-term tests” at the Northrop Grumman facility to ensure that the world’s most complex telescope can go through the launch phase smoothly and that ‘it will work as expected once released into space. These operations completed, the observatory is now preparing for its trip to Guyana during which it will cross the Panama Canal. These shipping preparations will be completed in September.
In the meantime, teams from the Mission Operations Center (MOC) at the Space Telescope Science Institute (Baltimore, United States) continue to verify the complex communications network that the James Webb Telescope will use to transmit its data to Earth. Mission managers will also rely on this network to send their orders to the instruments.
Once the James Webb Telescope arrives in French Guiana, teams will need to ensure that the observatory has not been damaged during the expedition. If all goes well, they will then load the propellant tanks with hydrazine-based fuel and a nitrogen tetroxide oxidizer that the observatory will need to power its thrusters in order to maintain its orbit.
In this image, engineers spray dry ice to clean part of the telescope’s large mirror without scratching it. These operations took place at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Credit: Chris Gunn / NASA
About six months of commissioning
Next, the engineering teams will couple the observatory to its launcher, an Ariane 5 rocket supplied by ESA (European Space Agency). The launch is still officially scheduled for October 31, but there’s a good chance it will be pushed back to mid-November.
About 26 minutes after takeoff, the observatory will separate from the rocket and its solar panel will deploy automatically. It should then return to orbit about a month later. During this time, all of the observatory’s instruments, starting with its enormous sun visor, will be deployed one by one from the control center.
Note that the telescope will not orbit the Earth, as Hubble can, but around the Sun, 1.5 million kilometers from Earth on the second Lagrange point (L2). The peculiarity of this orbit is that it will allow the telescope to stay aligned with our planet, while allowing the sunshade to protect it from the light and heat of our star, as well as the Earth-Moon system. To probe the early universe, the James Webb Telescope will indeed need to be cool!
Once the observatory has cooled and stabilized at its optimum operating temperature (less than 45 ° C above absolute zero), it will undergo a commissioning period that could last up to six months during which all its instruments and optics will be calibrated. Scientific operations should then be able to begin with a single objective: to revolutionize our approach to the universe.