Image of the Week

9 June 2021: Vera C. Rubin Observatory basks under a cloudless sky in this image. The observatory is currently under construction atop Cerro Pachón in Chile. If you look closely, you can see a sliver of the teal-blue steel of the telescope structure within the nearly finished dome. Further sheets of the same blue steel are neatly stacked in the building site nearby. Beyond Cerro Pachón, the domes of Cerro Tololo Inter-American Observatory are visible on a nearby summit, and other ridges of the Andean foothills fade into blue in the distance. When complete, Rubin Observatory will use its 8.4-meter telescope and 3200-megapixel camera to conduct an unprecedented, multi-color, decade-long survey of the optical sky called the Legacy Survey of Space and Time (LSST). The camera will be the largest ever constructed for astronomy and will weigh almost 2800 kilograms — more than a rhinoceros!

2 June 2021: The night sky overflows with light and color in this long-exposure image from Kitt Peak National Observatory, a Program of NSF’s NOIRLab. The starry band of the Milky Way spans the upper left of the image, and the subtle reddish colors of airglow tint the sky in scarlet. The long exposure time allows the camera to collect sufficient light that the stars are picked out in sharp detail. However, that long exposure time also means that the lights from both the interior of the WIYN 0.9-meter Telescope’s dome and the distant city of Tucson in the far left appear to be very bright. In reality, artificial lights around the telescopes are tightly controlled, and the observatory is intentionally located far enough from human dwellings that there is limited light pollution. As well as producing a vibrant skyscape, this long exposure time has also stretched the stars at the top of …

26 May 2021: This image shows the planetary nebula Sh2-42 in the constellation Sagittarius, and was captured by using the SMARTS 0.9-meter Telescope at Cerro Tololo Inter-American Observatory, a Program of NSF’s NOIRLab. Despite the name, planetary nebulae have nothing to do with planets — they are spectacular funeral pyres formed by red giant stars at the end of their lives. As these giant stars expand and throw their outer gaseous layers into space, the hot exposed core of the star ionizes the surrounding material, causing it to glow in a range of vivid colours. As it reaches the end of its life, our own Sun is expected to form a planetary nebula — but not for another 5 billion years!

19 May 2021: In this image, one of the Maunakea observatories appears to be hanging by a golden thread. In reality, the thread is a beam of light, and it is not descending from the sky, but is pointing upwards from the telescope itself. It originates from Gemini North, part of the international Gemini Observatory, a Program of NSF’s NOIRLab. The light beam is a laser guide star , and its purpose is to form an artificial constellation of stars in the atmosphere, 90 kilometers (56 miles) from the Earth’s surface. Intuitively it seems that the laser beam must be extraordinarily powerful. Remarkably, however, the laser guide star produces about as much energy as a bedside lamp. The reason why light with so little energy can beam so far into the atmosphere is because laser beams are incredibly focused, with all the energy concentrated in a single direction. The laser beam is …

12 May 2021: This snapshot captures the towering Víctor M. Blanco 4-meter Telescope and one of the four SMARTS Consortium telescopes, both set against the spectacular backdrop of the early evening sky. The dome of the SMARTS 1.5-meter Telescope — which is actually gleaming white — has been illuminated in scarlet light, giving the observatory an unusually vivid appearance. This image was captured at Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF’s NOIRLab. The observatory’s high-altitude desert location — it lies 2200 meters (7200 feet) above sea level at the edge of Chile’s Atacama Desert — provides astronomers with the pristine conditions needed to observe the Universe.

5 May 2021: A beam of light shining into the night sky illuminated by moonlight. Its origin is Gemini North, one of the twin telescopes that make up the international Gemini Observatory, a Program of NSF’s NOIRLab. The light is in fact a laser guide star, and it serves a remarkable purpose. The laser guide star’s light encounters a layer of sodium high in the Earth’s atmosphere (about 90 kilometers (56 miles overhead) where it creates an artificial star. This artificial star is used as a reference by Gemini North, to allow the telescope to correct for much of the turbulence of Earth’s atmosphere. The artificial star is too faint to be seen by human eyes. The laser beam itself is visible, but not at large distances. So as striking as this image is, the inhabitants of Hawai‘i are not disturbed by a night sky filled with bright laser beams!

28 April 2021: In this striking image light from the Sun breaks over the craggy ridge at Kitt Peak National Observatory, a Program of NSF’s NOIRLab, silhouetting the 4-meter Nicholas U. Mayall Telescope and the tops of other telescope domes. Located at an altitude of 2096 meters (6877 feet) in southern Arizona, Kitt Peak hosts more than 20 telescopes for nighttime astronomy and daytime solar studies — making it one of the largest collections of astronomical instruments in the northern hemisphere. The eighteen-story Nicholas U. Mayall Telescope jutting above the ridge is a distinctive feature of the Kitt Peak skyline. It is the largest telescope at the observatory, and its tower and dome can be seen from over 80 kilometers (50 miles) away.

21 April 2021: This image of the week features the Telescope Mount Assembly of the 8.4-meter Simonyi Survey Telescope at Vera C. Rubin Observatory, currently under construction atop Cerro Pachón in Chile. This image shows the telescope frame prior to the mounting of the Top-End Assembly, a 28-metric tonne (31-ton) steel structure which was installed last month. Once the telescope is completed, the Top-End Assembly will support the telescope’s secondary mirror and the Rubin Observatory LSST Camera — the largest digital camera ever constructed for astronomy. The Simonyi Telescope will carry out the Rubin Observatory Legacy Survey of Space and Time (LSST), a 10-year observing campaign that will address some of the most pressing questions about the structure and evolution of the Universe.

14 April 2021: This image is so beautiful that it could almost be a painting, but it is real. It has been produced using observations made at the SMARTS 0.9-meter Telescope at the Cerro Tololo Inter-American Observatory (CTIO), which is a Program of NSF’s NOIRLab. It features a reflection nebula known as NGC 2626, which lies 3300 light-years from Earth. Reflection nebulae are not luminous themselves, but they reflect light from a nearby star or stars. The light scatters off the dust particles in the nebulae, which often results in reflection nebulae having a blue tint, because blue light scatters more efficiently. This is the same phenomenon that makes the sky on Earth appear blue — the laws of physics are the same throughout our Universe! The red nebulosities are glowing hydrogen gas.

7 April 2021: It looks as though the stars are falling through the sky above Gemini North, the northern-hemisphere-based half of the international Gemini Observatory, a Program of NSF’s NOIRLab. The stars, however, have not suddenly all shifted across the Universe. The trails of starlight are due to the movement of the Earth itself. We know that the Earth rotates once on its own axis every 24 hours, giving us daytime and nighttime, but it is still strange to see such a visual reminder. The photographer, Jason Chu, took a very long exposure in order to capture the changing view of the stars as the Earth rotated. The result is this spectacular image with the faint red glow of the Gemini North laser guide star system emanating from its open dome, the taillight of a passing car crossing the dark road below and sweeping star trails in the background.

31 March 2021: This gorgeous image resembles an inky patch of space that has been smudged by a giant celestial thumbprint. Actually the object is a planetary nebula named PN M 2-53. It was imaged using the Gemini North telescope of the international Gemini Observatory, a Program of NSF’s NOIRLab. Planetary nebulae have a wildly misleading name, as they have nothing to do with planets — or even exoplanets. The misnomer originates from the late 1700s, when astronomers thought that the gaseous structures resembled planets. Planetary nebulae are actually formed by some dying stars, right at the end of their lives. The layers of gas and dust shed by the dying stars are lit by their remaining cores, creating a planetary nebula. Despite its inaccuracy, the name has stuck!

24 March 2021: A gathering of telescopes perch near the summit of Maunakea, a dormant volcano on Hawai‘i Island with an elevation of 4207 meters (13,803 feet), making it an ideal location for astronomical observations. Nearly centered under the rising full Moon is Gemini North, the northern member of the international Gemini Observatory, a Program of NSF’s NOIRLab. Its twin telescope, Gemini South, has its home in Chile. The two telescopes are practically identical, each with an impressive 8-meter primary mirror to collect light. Whilst the twin telescopes will never meet, their separation serves a purpose — between them, they can observe almost the entirety of the night sky. The skies of the northern hemisphere are the realm of Gemini North.

17 March 2021: The three buildings featured in this image house an important trio of telescopes: the SMARTS 1.0-meter Telescope, the Curtis Schmidt Telescope, and the Víctor M. Blanco 4-meter Telescope (far right). They are situated at the Cerro Tololo Inter-American Observatory, a Program of NSF’s NOIRLab. Clustered under the extraordinarily vivid sky, this telescope team is poised for action. The Blanco has actually been active since 1976. It is an optical telescope, which means that it collects light with similar wavelengths to that seen by the human eye. The lens in a human eye only has a diameter of about 1 cm, but the 4-meter primary mirror in the Blanco collects a whopping 160,000 times as much light as the human eye does.

10 March 2021: The blackness of space is punctuated by bright dots. This image could almost be mistaken for a particularly detailed shot of the night sky as seen from Earth, full of stars. Appearances, however, can be deceptive. This image was taken from Earthʻs southern hemisphere, but the bright dots are not stars — they are galaxies. In fact, the distinctive, ring-shaped galaxy on the right is LEDA 14884. This image was built up using data from the Dark Energy Survey, an ambitious project which mapped hundreds of millions of galaxies across the Universe. This was done using the Dark Energy Camera (DECam), an instrument built by the Department of Energy and mounted at the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF’s NOIRLab. Looking at this incredible image, with its thousands of wildly diverse galaxies, it is mind-boggling to recall that only about 100 …

3 March 2021: On 2 March 2021 at Vera C. Rubin Observatory in Chile, the top-end assembly for the telescope was lowered through the observatory enclosure by a giant, 500-ton capacity crane. The top-end assembly holds the 3.5-meter convex secondary mirror and the giant 3-ton LSST Camera. The camera optics consist of three large fused-silica lenses and a set of astronomical filters. The installation of the top-end is an important step in the completion of the Telescope Mount Assembly, which will hold and precisely position the 8.4-meter diameter main mirror called M1M3 (which doubles as both primary and tertiary mirror) and the top end assembly. Rubin’s innovative optical design is needed to deliver a whopping 3.5-degree field of view on the sky which illuminates the huge 60-centimeter (2 feet)-diameter flat focal plane filled with sensors totaling 3200 megapixels. Rubin Observatory and its 10 year survey of the sky will shed light on some …

24 February 2021: The telescopes at Maunakea sit calmly beneath a sky filled with extraordinary light. Amongst these telescopes is Gemini North, the northern member of the international Gemini Observatory, a Program of NSF’s NOIRLab. Gemini North sits at an altitude of around 4200 meters (13,800 feet). Not only does this altitude facilitate world-class astronomical observations, but Gemini North’s nighttime Cloudcams were able to capture the extraordinary light phenomena seen on the right side of the image. The column of blue and red lights surrounded by a bright blaze of white light appears so otherworldly that it looks like it must be a special effect. This breathtaking image, however, is entirely real. It features the lightning phenomena named a red sprite. Red sprites are distinctive because of their color, and also the direction in which they strike. The red and blue lights are shooting down from 50-90 kilometers toward the top of the …

17 February 2021: A crack team, each with their own remarkable abilities, are gathered together in a remote spot in the Chilean Andes. Together, they will help uncover some of the Universe’s biggest secrets. It sounds like the premise for an exciting superhero movie! But it’s just another day at the Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF’s NOIRLab, where a collection of remarkable telescopes are situated. The Víctor M. Blanco 4-meter Telescope (far left) is a reflecting telescope, and it has the biggest primary mirror at CTIO. The primary mirror in a reflecting telescope is used to collect light from the night sky, which is then reflected onto another surface inside the telescope. In addition to the team of telescopes surrounding it, the Blanco has a nearly identical twin, the Nicholas U. Mayall 4-meter Telescope. The Mayall is located at Kitt Peak National Observatory, another NOIRLab Program.

10 February 2021: In this Image of the Week the sunrise lights up a snow-capped Maunakea, home to the Maunakea Observatories that include the northern member of the international Gemini Observatory, a Program of NSFʻs NOIRLab. When most people think of Hawai‘i, what comes to mind is a warm and sunny climate. However, during the northern winter months, snow sometimes blankets the two largest mountains on Hawaiʻi Island, Maunakea and Maunaloa, creating captivating winter scenes. Gemini North on Maunakea saw snow on 25 January 2021 and the snow remains even now on 10 February, 2021.

3 February 2021: We typically see photographs of telescopes at night, juxtaposed against a sky full of stars. In this gorgeous sun-drenched image, we glimpse a different side of the Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF’s NOIRLab. The early morning Sun bathes the observatory in a warm light. The locale might look inviting, but it actually is not a very friendly environment for humans. Modern observatories are typically built at locations that are “high and dry”. This is because the atmosphere needs to be as thin and arid as possible in order to get the best possible observations. Furthermore, the telescopes must be located far from highly developed areas, in order to avoid light pollution. Therefore observatories such as the CTIO represent concentrations of highly technical buildings in otherwise relatively deserted landscapes.

27 January 2021: The emission nebula Sh2-54 glows brightly in this image from the SMARTS 0.9-meter Telescope at Cerro Tololo Inter-American Observatory, a Program of NSF’s NOIRLab. Gathering the fine details of this particular image required almost twenty minutes of observations and three different wavelength filters. Situated within the constellation of Serpens (The Serpent), Sh2-54 forms part of a much wider nebulosity which includes the famous Eagle Nebula. Serpens is a unique constellation, the only one of the official 88 used today that is split into two unconnected parts: Serpens Caput — the Serpent’s Head — and Serpens Cauda — The Serpent’s Tail.