NASA and the James Webb Space Telescope team have spoken for years about how the observatory, once it is in place and fully aligned and calibratated, will revolutionize astronomy and lead to a bounty of space discoveries.
The agency has now released some early images, produced before the process of fine-tuning the telescope is finished. And they visually certainly do make the case for the JWST to be precisely the ground-breaking pioneer long promised.
Its goals are to explore the earliest light in the universe, to possibly observe the first stars and galaxies being born and — for the exoplanet and astrobiology community — to study exoplanets and their atmospheres with unprecedented precision.
A sample of the extraordinary precision Webb will provide can be seen in the images above, which are of the same region of the Large Magellanic Cloud, a satellite galaxy of the Milky Way.
The image on the left was taken with one of the earliest Great Observatory telescopes — the retired Spitzer Space Telescope, and its Infrared Array Camera. The observatory was launched in 2003 and was a pioneering instrument in its time.
But on the right is the new JWST image of the Large Magellenic Cloud, taken with its Mid-Infrared Instrument, or MIRI camera. The galaxy’s wispy gases and bright stars make it apparent why astronomers are ecstatic about the new worlds that will become visible to them.
“This is a really nice science example of what Webb will do for us in the coming years,” Christopher Evans, a Webb project scientist with the European Space Agency, said of the images in at a recent NASA press conference.
“This is just going to give us an amazing view of the processes in a different galaxy for the first time, cutting through the dust,” Evans said.
Michael McElwain, a Webb observatory project scientist at NASA’s Goddard Space Flight Center, said he was “delighted to report that the telescope alignment has been completed with performance even better than we had anticipated.”
The Webb observatory can see so much better because it has a significantly larger primary mirror than on past observatories (the Hubble Space Telescope main mirror is 2.4 meters in diameter versus meters for JWST) and has improved detectors. Webb sees the cosmos in the infrared and near-infrared wavelengths, but the images will be translated into visible light
The preparation and testing of the telescope’s science instruments (a process called commissioning) will take about two months to complete. Only once the commissioning is complete can Webb begin taking the scientific images that will define its tenure in space.
Webb sits at an observational point called L2 nearly 1 million miles from Earth, where it will look further back in time than any other telescope, including the previous champion, the Hubble. The long-lasting Hubble will continue to operate alongside Webb once the latter is operational.
Klaus Pontoppidan, a Webb project scientist at the Space Telescope Science Institute, said in the briefing that the chief differences between the most recent images and the ones to come are that the former were taken to test the telescope’s ability to see clearly, whereas the latter will test the telescope’s ability to image science targets.
Pontoppidan wouldn’t elaborate on what Webb team will capture in the early release observations — the targets are a “surprise,” he said.
The Webb viewing schedule includes early release programs that will give provide images and guidance to future observers on how the telescope works.
The exoplanet early release program will focus on hot Jupiters and will study the atmospheric chemistry of several well known planets. Here is a Many Worlds story about the exoplanet early release program and here is a story about other Cycle 1 exoplanet projects.
The telescope was designed to operate for five years at minimum, but its precise launch in December left it with enough fuel to stay in position as many as 20 years.