Picture of the Month

28 February 2023
This observation from the NASA/ESA/CSA James Webb Space Telescope features the massive galaxy cluster RX J2129. Due to Gravitational lensing, this observation contains three different images of the same supernova-hosting galaxy, which you can see in closer detail here. Gravitational lensing occurs when a massive celestial body causes a sufficient curvature of spacetime to bend the path of light travelling past or through it, almost like a vast lens. In this case, the lens is the galaxy cluster RX J2129, located around 3.2 billion light-years from Earth in the constellation Aquarius. Gravitational lensing can cause background objects to appear strangely distorted, as can be seen by the concentric arcs of light in the upper right of this image. Astronomers discovered the supernova in the triply-lensed background galaxy using observations from the NASA/ESA Hubble Space Telescope, and they suspected that they had found a very distant Type Ia supernova. These supernovae …

31 January 2023
A crowded field of galaxies throngs this Picture of the Month from the NASA/ESA/CSA James Webb Space Telescope, along with bright stars crowned with Webb’s signature six-pointed diffraction spikes. The large spiral galaxy at the base of this image is accompanied by a profusion of smaller, more distant galaxies which range from fully-fledged spirals to mere bright smudges. Named LEDA 2046648, it is situated a little over a billion light-years from Earth, in the constellation Hercules. One of Webb’s principle science goals is to observe distant galaxies in the early universe to understand the details of their formation, evolution, and composition. Webb’s keen infrared vision helps the telescope peer back in time, as the light from these distant galaxies is redshifted towards infrared wavelengths. Comparing these systems with galaxies in the local universe will help astronomers understand how galaxies grew to form the structure we see today. Webb will also …

21 December 2022
This image is dominated by NGC 7469, a luminous, face-on spiral galaxy approximately 90 000 light-years in diameter that lies roughly 220 million light-years from Earth in the constellation Pegasus. Its companion galaxy IC 5283 is partly visible in the lower left portion of this image. This spiral galaxy has recently been studied as part of the Great Observatories All-sky LIRGs Survey (GOALS) Early Release Science program with the NASA/ESA/CSA James Webb Space Telescope, which aims to study the physics of star formation, black hole growth, and feedback in four nearby, merging luminous infrared galaxies. Other galaxies studied as part of the survey include previous ESA/Webb Pictures of the Month II ZW 096 and IC 1623. NGC 7469 is home to an active galactic nucleus (AGN), which is an extremely bright central region that is dominated by the light emitted by dust and gas as it falls into the galaxy’s …

30 November 2022
A merging galaxy pair cavort in this image captured by the NASA/ESA/CSA James Webb Space Telescope. This pair of galaxies, known to astronomers as II ZW 96, is roughly 500 million light-years from Earth and lies in the constellation Delphinus, close to the celestial equator. As well as the wild swirl of the merging galaxies, a menagerie of background galaxies are dotted throughout the image.The two galaxies are in the process of merging and as a result have a chaotic, disturbed shape. The bright cores of the two galaxies are connected by bright tendrils of star-forming regions, and the spiral arms of the lower galaxy have been twisted out of shape by the gravitational perturbation of the galaxy merger. It is these star-forming regions that made II ZW 96 such a tempting target for Webb; the galaxy pair is particularly bright at infrared wavelengths thanks to the presence of the …

25 October 2022
This image from the NASA/ESA/CSA James Webb Space Telescope depicts IC 1623, an entwined pair of interacting galaxies which lies around 270 million light-years from Earth in the constellation Cetus. The two galaxies in IC 1623 are plunging headlong into one another in a process known as a galaxy merger. Their collision has ignited a frenzied spate of star formation known as a starburst, creating new stars at a rate more than twenty times that of the Milky Way galaxy. This interacting galaxy system is particularly bright at infrared wavelengths, making it a perfect proving ground for Webb’s ability to study luminous galaxies. A team of astronomers captured IC 1623 across the infrared portions of the electromagnetic spectrum using a trio of Webb’s cutting-edge scientific instruments: MIRI, NIRSpec, and NIRCam. In so doing, they provided an abundance of data that will allow the astronomical community at large to fully explore …

27 September 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 …

29 August 2022
This image from the NASA/ESA/CSA James Webb Space Telescope shows the heart of M74, otherwise known as the Phantom Galaxy. Webb’s sharp vision has revealed delicate filaments of gas and dust in the grandiose spiral arms which wind outwards from the centre of this image. A lack of gas in the nuclear region also provides an unobscured view of the nuclear star cluster at the galaxy's centre. M74 is a particular class of spiral galaxy known as a ‘grand design spiral’, meaning that its spiral arms are prominent and well-defined, unlike the patchy and ragged structure seen in some spiral galaxies. The Phantom Galaxy is around 32 million light-years away from Earth in the constellation Pisces, and lies almost face-on to Earth. This, coupled with its well-defined spiral arms, makes it a favourite target for astronomers studying the origin and structure of galactic spirals. Webb gazed into M74 with its …

12 July 2022
Webb's Mid-InfraRed Instrument (MIRI) shows never-before-seen details of Stephan’s Quintet, a visual grouping of five galaxies, in this image. MIRI pierced through dust-enshrouded regions to reveal huge shock waves and tidal tails, gas and stars stripped from the outer regions of the galaxies by interactions. It also unveiled hidden areas of star formation. The new information from MIRI provides invaluable insights into how galactic interactions may have driven galaxy evolution in the early universe. This image was released as part of the first set of images from the NASA/ESA/CSA James Webb Space Telescope on 12 July 2022 (for a full array of Webb’s first images and spectra, including downloadable files, please visit this page). This image contains one more MIRI filter than was used in the NIRCam-MIRI composite picture. The image processing specialists at the Space Telescope Science Institute in Baltimore opted to use all three MIRI filters and the …

27 June 2022
Webb’s Fine Guidance Sensor (FGS) – developed by the Canadian Space Agency – has captured a special view of stars and galaxies that provides a tantalising glimpse at what the telescope’s science instruments will reveal in the coming weeks, months, and years. The FGS has always been capable of capturing imagery, but its primary purpose is to enable accurate science measurements and imaging with precision pointing. When it does capture imagery, the imagery is typically not kept: Given the limited communications bandwidth between L2 and Earth, Webb only sends data from up to two science instruments at a time. But during a week-long stability test in May, it occurred to the team that they could keep the imagery that was being captured because there was available data transfer bandwidth. The resulting engineering test image has some rough-around-the-edges qualities to it. It was not optimised to be a science observation; rather, …

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.