08 Sep 2021
$9 billion observatory will be shipped to French Guiana launch site via Panama Canal.
NASA and the European Space Agency (ESA) have confirmed that they now plan to launch the James Webb Space Telescope (JWST) on December 18.
The new launch date, pushed back a couple of months from October, should represent the last of the delays that have plagued the project from the outset.
An international partnership between NASA, ESA, and the Canadian Space Agency (CSA), the telescope itself is expected to arrive at ESA’s launch site in French Guiana by the end of this month - after travelling from Long Beach, California, via the Panama Canal.
During last December’s SPIE Astronomical Telescopes and Instrumentation Digital Forum, Charlie Atkinson, chief engineer for JWST at key contractor Northrop Grumman, indicated that launch should take place approximately three months after the cargo arrives at the Kourou spaceport.
Yesterday ESA confirmed that the upper stage of the Ariane 5 rocket that will carry the observatory into space had arrived safely in Kourou on September 3.
Conceived as a follow-up to the Hubble Space Telescope but with a much larger mirror and far superior infrared imaging capability, JWST’s original budget was “only” $500 million and the observatory was initially pencilled in for launch in 2007.
But after a major redesign, a ballooning budget, and, for a time, the very real threat of cancellation by US Congress, astronomers are finally set to witness the most powerful space telescope ever built fired towards its destination, the second Lagrange point (L2).
“Webb is an exemplary mission that signifies the epitome of perseverance,” commented Gregory L. Robinson, Webb’s program director at NASA’s headquarters in Washington, DC.
After separation from the Ariane 5, JWST will take four more weeks to reach L2, a point in space 1.5 million kilometers from Earth in the direction away from the sun.
L2 is not a fixed point, but instead follows Earth around the sun in a stable orbit - from where JWST’s sunshield will block light and heat from the sun on one side and look into space from the other.
From L2, the telescope and its four major instruments are expected to capture unprecedented images of the cosmos, from galaxies on the edge of the known universe and distant Earth-like exoplanets, to richly detailed views of objects that are much closer to home.
“[JWST’s] revolutionary technology will explore every phase of cosmic history - from within our solar system to the most distant observable galaxies in the early universe, and everything in between,” stated NASA.
“[It] will reveal new and unexpected discoveries, and help humankind understand the origins of the universe and our place in it.”
Critical to making those observations is JWST’s infrared imaging capability, based around a suite of state-of-the-art cameras, spectrographs and coronagraphs operating in the near-infrared and mid-infrared regions of the spectrum.
“[JWST] will cover longer wavelengths of light than the Hubble Space Telescope and has a 100 times improved sensitivity, which opens up a new window to the universe,” says ESA.
“The longer wavelengths enable [JWST] to uncover hidden parts of our solar system, peer inside dust clouds where stars and planetary systems are forming, reveal the composition of exoplanets' atmospheres in more detail, and look farther back in time to see the first galaxies that formed in the early universe.”
Built by the University of Arizona, NIRCam will cover the infrared wavelength range at 0.6-5 µm, detecting light from some of the earliest stars and galaxies in the process of formation, as well as young stars in the Milky Way, and smaller objects in the Kuiper Belt that lies just outside our solar system.
Provided by ESA but with some key components from NASA, NIRSpec will operate over the same wavelengths as NIRCam and generate spectra for thousands of galaxies during the JWST mission, partly thanks to a novel microshutter that allows it to observe 100 objects simultaneously.
Also from a NASA/ESA collaboration, MIRI features both a camera and a spectrograph operating across the mid-infrared spectrum at 5-28 µm. Those wavelengths will allow it to see the red-shifted light of some of the most distant galaxies, as well as newly forming stars, and faint comets.
Developed by CSA, the Fine Guidance Sensor (FGS) and Near Infrared Imager and Slitless Spectrograph (NIISS) instrument will operate at 0.8-5 µm and be used to detect and investigate exoplanets, among other things.