Picture of the Month

23 September 2022
This MIRI test image (at 7.7 microns) shows part of the Large Magellanic Cloud. This small satellite galaxy of the Milky Way provided a dense star field to test Webb’s performance. Here, a close-up of the MIRI image is compared to a past image of the same target taken with NASA’s Spitzer Space Telescope’s Infrared Array Camera (at 8.0 microns). The retired Spitzer was the first observatory to provide high-resolution images of the near- and mid-infrared Universe. Webb, by virtue of its significantly larger primary mirror and improved detectors, will allow us to see the infrared sky with improved clarity, enabling even more discoveries. For example, Webb’s MIRI image shows the interstellar gas in unprecedented detail. Here, you can see the emission from ‘polycyclic aromatic hydrocarbons’ – molecules of carbon and hydrogen that play an important role in the thermal balance and chemistry of interstellar gas. When Webb is ready …

27 June 2022
This spectacular image features the spiral galaxy IC 5332, shown here in unprecedented detail thanks to observations from the Mid-InfraRed Instrument (MIRI), which is mounted on the NASA/ESA/CSA James Webb Space Telescope. IC 5332 lies over 29 million light-years from Earth, and has a diameter of roughly 66 000 light-years, making it about a third smaller than the Milky Way. It is notable for being almost perfectly face-on with respect to Earth, allowing us to admire the symmetrical sweep of its spiral arms. MIRI is the only Webb instrument that is sensitive to the mid-infrared region of the electromagnetic spectrum (specifically in the 5 µm – 28 µm wavelength range); Webb’s other instruments all operate in the near-infrared. One of MIRI’s most remarkable features is that it operates 33 °C below the rest of the observatory at the frosty temperature of –266 °C. That means that MIRI operates in an …

9 May 2022
This MIRI test image (at 7.7 microns) shows part of the Large Magellanic Cloud. This small satellite galaxy of the Milky Way provided a dense star field to test Webb’s performance. Here, a close-up of the MIRI image is compared to a past image of the same target taken with NASA’s Spitzer Space Telescope’s Infrared Array Camera (at 8.0 microns). The retired Spitzer was the first observatory to provide high-resolution images of the near- and mid-infrared Universe. Webb, by virtue of its significantly larger primary mirror and improved detectors, will allow us to see the infrared sky with improved clarity, enabling even more discoveries. For example, Webb’s MIRI image shows the interstellar gas in unprecedented detail. Here, you can see the emission from ‘polycyclic aromatic hydrocarbons’ – molecules of carbon and hydrogen that play an important role in the thermal balance and chemistry of interstellar gas. When Webb is ready …

28 April 2022
Alignment of the NASA/ESA/CSA James Webb Space Telescope is now complete. After full review, the observatory has been confirmed to be capable of capturing crisp, well-focused images with each of its four powerful onboard science instruments. Upon completing the seventh and final stage of telescope alignment, the team held a set of key decision meetings and unanimously agreed that Webb is ready to move forward into its next and final series of preparations, known as science instrument commissioning. This process of setting up and testing the instruments will take about two months before scientific operations begin in the summer. The alignment of the telescope across all of Webb’s instruments can be seen in a series of images that captures the observatory’s full field of view. Engineering images of sharply focused stars in the field of view of each instrument demonstrate that the telescope is fully aligned and in focus. For …

16 March 2022
On 11 March 2022, the NASA/ESA/CSA James Webb Space Telescope (Webb) team completed the stage of mirror alignment known as "fine phasing". Although there are months to go before Webb ultimately delivers its new view of the cosmos, achieving this milestone means the team is confident that Webb’s first-of-its-kind optical system is working as well as possible. At this key stage in the commissioning of Webb’s Optical Telescope Element, every optical parameter that has been checked and tested is performing at, or above, expectations. The team also found no critical issues and no measurable contamination or blockages to Webb’s optical path: the observatory is able to successfully gather light from distant objects and deliver it to its instruments without issue. At this stage of Webb’s mirror alignment, each of the primary mirror segments has been adjusted to produce one unified image of the same star using only Webb’s primary imager, …

11 February 2022
The NASA/ESA/CSA James Webb Space Telescope is nearing completion of the first phase of the months-long process of aligning the observatory’s primary mirror using the Near Infrared Camera (NIRCam) instrument. The team’s challenge was twofold: confirm that NIRCam was ready to collect light from celestial objects, and then identify starlight from the same star in each of the 18 primary mirror segments. The result is an image mosaic of 18 randomly organised dots of starlight, the product of Webb’s unaligned mirror segments all reflecting light from the same star back at Webb’s secondary mirror and into NIRCam’s detectors. What looks like a simple image of blurry starlight now becomes the foundation to align and focus the telescope in order for Webb to deliver unprecedented views of the universe this summer. Over the next month or so, the team will gradually adjust the mirror segments until the 18 images become a …

3 January 2022
The NASA/ESA/CSA James Webb Space Telescope lifted off on an Ariane 5 rocket from Europe’s Spaceport in French Guiana, at 13:20 CET on 25 December on its exciting mission to unlock the secrets of the Universe. Following launch and separation from the rocket, Webb’s mission operations centre in Baltimore, USA confirmed Webb deployed its solar array and is in good condition, marking the launch a success. In the coming month, Webb, an international partnership between NASA, ESA and the Canadian Space Agency (CSA), will travel to its destination: the second Lagrange point (L2), where it will study the Universe in infrared.