Image of the Week

30 September 2020: The Milky Way resembles a waterfall rushing down the colorful night sky above Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF NOIRLab. The green-tinged light on the horizon is airglow, originating from the naturally occurring gases in Earth’s atmosphere. Airglow is present at all latitudes but is incredibly dim at visible wavelengths, making it difficult to spot with the naked eye but vivid and bright with long exposure photography. While the horizon softly glows with light, the skies above the telescopes remain awash with stars.

23 September 2020: Last week, on the night of Thursday 17 September 2020 10:52 pm, a very bright meteor was reported by more than 25 eyewitnesses in and around Tucson and Phoenix, Arizona. The phenomenon, also known as a fireball or bolide, was also spotted by one of the robotic cameras at Kitt Peak National Observatory (KPNO), a Program of NSF NOIRLab: an all-sky camera operated by the University of Arizona’s Spacewatch who operates the Spacewatch 0.9-meter Telescope and the Spacewatch 1.8-meter Telescope (seen in the image as the white dome near the top of the image respectively on the left). The image shows the fireball, brighter than the full Moon, entering from the south (bottom) of the image and moving north. Its color is a clear blue. The aim of Spacewatch’s telescopes is very relevant: to observe Near-Earth Asteroids which have been found to pose an impact hazard to Earth. KPNO remains …

16 September 2020: The glowing light suffusing the night sky in this photograph is due to two fascinating effects — zodiacal light and airglow. The first effect, zodiacal light, is due to sunlight scattered by interplanetary dust in our Solar System, and causes the dim white vertical gleam dominating the left hand side of this image. Airglow, on the other hand, originates in Earth’s own atmosphere. It is visible as bands of colored light along the horizon to the right of the Víctor M. Blanco 4-meter Telescope of Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF NOIRLab.

9 September 2020: The full Moon rises behind the heliostat of the McMath-Pierce Solar Telescope at Kitt Peak National Observatory (KPNO), a Program of NSF NOIRLab. The heliostat has a 2.03-meter (80-inch) mirror that reflects sunlight into the optical path of the telescope. The McMath-Pierce Solar Telescope was the largest solar telescope in the world upon its completion in 1962, a title it held until the first light of the National Solar Observatory’s Daniel K. Inouye Solar Telescope in December 2019. The interior of the McMath-Pierce Solar Telescope is currently being renovated to become the Windows on the Universe Center for Astronomy Outreach.

2 September 2020: Momentarily lit by the lights of a passing vehicle, this road leads to Gemini North, perched near the summit of Maunakea on Hawaiʻi Island. It is the northern member of the twin Gemini telescopes, which together comprise the international Gemini Observatory, a Program of NSF NOIRLab. There are no artificial lights present at the summit. However, the occasional wandering visitor will illuminate the domes with their headlights while in search of the world-famous views of Maunakea’s dark skies.

26 August 2020: This stunning image features NGC 3198, a galaxy that lies about 47 million light-years away in the constellation Ursa Major. This image was taken with the Mosaic instrument on the 4-meter Nicholas U. Mayall Telescope at Kitt Peak National Observatory, a Program of NSF NOIRLab, and shows the full extent of the galaxy, from the bright central bulge to the tenuous outer reaches of the tightly-wound spiral arms. Almost all the objects lurking in the background are galaxies or galaxy clusters — a sea of distant galaxies of all shapes, sizes, and orientations. Accurately measuring the distance to an astronomical object — everything from our own Sun to galaxies such as NGC 3198 — is an age-old challenge for astronomers, and requires a combination of measurements and methods. The galaxy at the heart of this image has played a part in this astronomical undertaking by allowing astronomers to calibrate astronomical …

19 August 2020: The Milky Way appears to be trapped in a crystal ball in this fisheye image taken at the Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF NOIRLab. Thanks to its remote location atop Cerro Tololo in northern Chile, CTIO enjoys a breathtaking panoramic view of the southern hemisphere’s night sky, and a spectacular perspective on the heart of the Milky Way. Though the dusty band of our Milky Way dominates this image, several of CTIO’s telescopes can also be seen along the edges. With more than 20 telescopes operating at the site, CTIO is fully equipped to take advantage of the pristine Chilean skies.

12 August 2020: Although this appears to be a daytime scene, star trails circle and illuminate the night sky in this long-exposure photo of Kitt Peak National Observatory (KPNO), a Program of NSF NOIRLab. The telescope visible at the highest peak is the Nicholas U. Mayall 4-meter Telescope and almost directly above it, at the center of the concentric star trails, sits the North Star, Polaris. As the Earth turns and the stars appear to move through the sky, Polaris remains stationary at the north celestial pole, our planet’s axis of rotation. The lights of Tucson, Arizona, glow yellow on the horizon about 89 kilometers (55 miles) to the northeast. The NOIRLab citizen science campaign Globe at Night enables stargazers of all ages to help monitor their city’s light pollution no matter where they are in the world.

5 August 2020: Pictured here is Gemini South, sitting on the summit of Cerro Pachón in Chile. It is the southern member of the pair of 8.1-meter telescopes, which together comprise the international Gemini Observatory, a Program of NSF NOIRLab. Gemini North saw its first light in 1999, and — appropriately for twin telescopes — Gemini South followed quickly behind with its first light in 2000. Since then, the united Gemini twins have provided a wealth of scientific observations. In this image, Gemini South is framed by the spectacular Milky Way, which — thanks to the photographic technique used — appears as a celestial arch, curving across the sky.

29 July 2020: This image shows an immersive view from inside the dome of the Víctor M. Blanco 4-meter Telescope at the Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF NOIRLab. The rotating dome is an impressive feat of engineering — designed to protect the delicate telescope from the elements. It weighs in at 430 tonnes (475 tons) and was built to withstand Chilean earthquakes. In addition to the Blanco’s dome, this photograph shows some of the equipment needed to run an astronomical observatory, ranging from calibration targets to good old-fashioned ladders! Glimpses of the mountains surrounding CTIO can be seen through the openings on the side of the dome, and a star-studded sky is visible overhead.

22 July 2020: The spiral galaxy NGC 2541 is shown in extravagant detail in this astronomical snapshot from the Nicholas U. Mayall 4-meter Telescope at Kitt Peak National Observatory, a Program of NSF NOIRLab. Astronomers recognize a variety of galaxy types, and NGC 2541 is classified as an unbarred spiral galaxy. These galaxies possess spectacular spiral arms like the ones shown here, but lack the central bar-shaped structure displayed by galaxies such as the Milky Way. NGC 2541 lies 37 million light-years from Earth in the constellation of Lynx (The Lynx). Sandwiched between the constellations of Ursa Major, Gemini, and Leo, Lynx is one of 10 new constellations established by the 17th century astronomer Johannes Hevelius. The constellation is composed of very faint stars, leading Hevelius to claim that only the lynx-eyed — people with exceptionally keen eyesight — would be able to spot this unobtrusive constellation.

15 July 2020: Comet NEOWISE — technically known as C/2020 F3 (NEOWISE) — is visible in this spectacular image of the pre-dawn sky to the right (East) of the Gemini North telescope on Maunakea in Hawai‘i, one of the pair of telescopes of the international Gemini Observatory, a Program of NSF NOIRLab. First discovered by the NEOWISE project using the Wide-field Infrared Survey Explorer space telescope in March 2020, the comet is a dirty snowball of gas, dust and ice roughly 5 km (3 miles) across. The curving golden tail of C/2020 F3 visible in this image is composed of gas and dust left behind as the comet swept through the inner Solar System. While creating a spectacle for stargazers, the comet’s passage close to the Sun will not happen again for another 6,800 years. Fortunately, there is still a chance to enjoy the show — Comet NEOWISE should be visible in the …

8 July 2020: Cameras allow us to see things which our eyes cannot! This atmospheric light painting was captured at Kitt Peak National Observatory (KPNO), a Program of NSF NOIRLab. The composition is framed by an inky sky and the spectacular arch of the McMath-Pierce Solar Telescope serves as a backdrop. Light painting — where a moving light source is captured with a long camera exposure — has been practiced for well over a century. It has both scientific and artistic applications. NOIRLab’s Colors of Nature Summer Academy explores the science of color and the role color plays in art and nature. Colors of Nature students learned about light painting and had the opportunity to practice the art on a trip to Kitt Peak with their families.

1 July 2020: The Milky Way spills across the night sky above the Víctor M. Blanco 4-meter Telescope at the Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF NOIRLab. Commissioned in 1974, the telescope was once the largest optical telescope south of the equator and remains an astronomical powerhouse to this day. This photograph captures the open dome of the telescope as it gazes upwards at the luminous band of stars and dust lanes making up our galaxy. Like all telescopes at CTIO, the Blanco benefits from the crystal-clear observing conditions in northern Chile — as you can see from this star-filled image!

24 June 2020: This image of the Gemini South telescope is so full of light that it is difficult to believe that it was captured at night. Gemini South is the southern half of the international Gemini Observatory, a Program of NSF NOIRLab. The wedge-shaped light on the right side of the photo is not from an artificial source (although there are city lights below it), but is a natural phenomenon known as zodiacal light. This occurs when sunlight is scattered off dust particles in the plane of our Solar System, causing part of the sky to become illuminated either after Sun-down or before Sun-up. The zodiac itself is a belt-shaped region on the sky, as seen from Earth, and is the apparent path of the planets in the sky. Gemini Observatory is named after one section of the zodiacal belt: Gemini, the constellation of the Twins.

17 June 2020: These whirling lines in the sky are the trails of stars after an hour-long exposure above Kitt Peak National Observatory (KPNO), a Program of NSF NOIRLab. The trails are shortest around the North Star, Polaris, a star that happens to coincide almost directly with the celestial north pole. The different colors in the trails reflect the different temperatures of the stars, with blue being the hottest stars and yellow/red the coolest. The telescope visible above the horizon is the Nicholas U. Mayall 4-meter Telescope, and the red glow on the mountain is caused by red lights used to ensure the eyes of visitors and staff remain dark adapted at night. The yellow glow on the horizon comes from Tucson, AZ, about 89 kilometers (55 miles) to the northeast. Over the past decade, light pollution like this has increased by 2% a year from many medium-sized and larger cities. To help …

10 June 2020: A shooting star streaks above Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF NOIRLab. Silhouetted against the night sky and the faint glow of Earth’s atmosphere are (from left to right) the Víctor M. Blanco 4-meter Telescope, the SMARTS 1.0-meter Telescope, the former University of Chile telescope, Las Cumbres Observatory 1-meter Telescope, and the KMTNet 1.6-meter Telescope. This image also features scattered boulders and desert plants (left) of Cerro Tololo. Before being purchased in 1967 to create an astronomical observatory, the land upon which CTIO stands supported a handful of subsistence farmers and goat herders. As the site’s old inhabitants voluntarily left for better prospects in nearby towns, much of the desert surrounding Cerro Tololo slowly returned to its natural state. Native species of desert plants and animals once in danger of extinction have returned to the area, and CTIO now hosts not only cutting-edge astronomical telescopes but also …

3 June 2020: The Silver Sliver Galaxy — more formally known as NGC 891 — is shown in this striking image from the Mosaic instrument on the 4-meter Nicholas U. Mayall Telescope at Kitt Peak National Observatory, a Program of NSF NOIRLab. NGC 891 is a spiral galaxy that lies almost perfectly edge-on to us, leading to its elongated appearance and its striking resemblance to our home galaxy, the Milky Way, as seen from the Earth. Since NGC 891 is oriented edge-on, it’s great for investigating the galactic fountain model. When stellar winds and supernovae from the disk of a galaxy eject gas into the surrounding medium, it can create condensation that rains back down onto the disk. The condensed gas then provides new fuel for star formation. In addition to the portrait of NGC 891, this image is littered with astronomical objects near and far — bright foreground stars from our own …

27 May 2020: We are so accustomed to skies full of light pollution that this photograph of the Milky Way appears almost unreal in its vividness. It was taken at the site of the KPNO 2.1-meter Telescope of the Kitt Peak National Observatory, a Program of NSF NOIRLab. The locations for advanced telescopes are chosen based on several key criteria: the lack of artificial light sources nearby, an arid environment, and clear skies. Not only do these conditions facilitate science-quality telescopic observations, but they make for extraordinary astrophotography.

20 May 2020: If you took only a quick glance at this image, you might think that the dark patches occulting the stars were smoke, rising from the ground. In fact this dazzling image — taken on Maunakea, Hawai’i at the northern site of the international Gemini Observatory (right), a program of NSF NOIRLab — shows the Milky Way in vivid detail, allowing us to see not only the stars, but the dusty regions which block their light. Tiny flecks mostly inorganic matter make up cosmic dust which in turn forms enormous obscuring clouds. The dark, smoke-like trail through the heart of the Milky Way is one such cloud, known as the Great Rift, containing more mass than 1 million suns