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NASA Astronomy Picture of the Day:

In this recent HiRISE view from the Mars Reconnaissance Orbiter, the little green dot indicated on the surface of the big Red Planet is the Perseverance Mars rover. Recorded on June 13, the car-sized, six-wheeled robot was imaged a day before completing a Martian marathon, traveling a total distance of 26.218 miles (42.195 kilometers) since it began exploring the surface of Mars. That equivalent marathon distance was achieved by Perseverance on its mission sol (Martian day) 1,890, after about 5 Earth years and 4 Earth months of driving. Perseverance is continuing to hunt for biosignatures. In the HiRISE image, the Mars rover's tracks can be seen leading to its location in an area west of its landing site in Jezero crater near an ancient river delta.

NASA Astronomy Picture of the Day:

In a cosmic vista you can never see, the Milky Way arcs through the night above Seoul, South Korea. Remarkably, this urban night skyscape reveals our galaxy's faintly luminous central region and dark obscuring dust clouds in spite of the brilliant city lights. To overcome the extreme light pollution of the metropolitan area and record faint cosmic details, an infrared filter was used to capture the night scene in a single exposure. While the filter transmits predominately infrared light, it still passes some visible light to give the scene a natural appearance. The view is from Seoul's Ttukseom Hangang Park, with the Han River and a well lit railway bridge across the foreground. The 123 story Lotte World Tower looms in the distance, the tallest building in South Korea.

Photo by Shingoo Lee

NASA Astronomy Picture of the Day:

The Sun has just set... in the opposite side of the sky. Pictured here are anticrepuscular rays apparently converging in the east in this image of the limestone plateau in the heart of the Hyblaean Mountains of southeastern Sicily, in Italy. How were these anticrepuscular rays formed, if the Sun wasn't there? After the Sun set (in the west, as usual) its light still illuminated a cloud higher up in the sky. Partially blocked by the cloud, the sunlight produced patterns of light and shadow, crossing the sky in parallel lines. Perspective makes it look like they converge in the east, in the same way that train tracks appear to meet in the distance. This effect can also happen at sunrise, only the directions are exchanged. In rare cases, both crepuscular and anticrepuscular rays can be seen at the same time.

Photo by Marcella Giulia Pace Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II)

NASA Astronomy Picture of the Day:

Why would the shadow of a space shuttle launch plume point toward the Moon? In early 2001 during a launch of Atlantis, the Sun, Earth, Moon, and rocket were all properly aligned for this photogenic coincidence. First, for the space shuttle's plume to cast a long shadow, the time of day must be either near sunrise or sunset. Only then will the shadow be its longest and extend all the way to the horizon. Finally, during a Full Moon, the Sun and Moon are on opposite sides of the sky. Just after sunset, for example, the Sun is slightly below the horizon, and, in the other direction, the Moon is slightly above the horizon. Therefore, as Atlantis blasted off, just after sunset, its shadow projected away from the Sun toward the opposite horizon, where the Full Moon happened to be.

NASA Astronomy Picture of the Day:

What would it look like to fly past Triton, the largest moon of planet Neptune? Only one spacecraft has ever done this -- and the images of this dramatic encounter have been gathered into a video. In 1989, the Voyager 2 robotic spacecraft shot through the Neptune system with cameras blazing. Triton is slightly smaller than Earth's Moon but has ice volcanoes and a surface rich in frozen nitrogen. The first sequence in the video shows Voyager's approach to Triton, which, with the exception of an overall false green tint, appears in approximately true color. The mysterious cantaloupe terrain seen under the spacecraft soon changed from light to dark, with the terminator of night crossing underneath. After closest approach, Voyager pivoted to see the departing moon, now visible as a diminishing crescent. In 2015, the robotic New Horizons spacecraft famously flew past Pluto, an orb of similar size to Triton. Almost Hyperspace: Random APOD Generator

Watch NASA's Astronomy Video of the Day

NASA Astronomy Picture of the Day:

Is this what will become of our Sun? Quite possibly. The first hint of our Sun's future was discovered inadvertently in 1764. At that time, Charles Messier was compiling a list of diffuse objects not to be confused with comets. The 27th object on Messier's list, now known as M27 or the Dumbbell Nebula, is a planetary nebula, one of the brightest planetary nebulas on the sky and visible with binoculars toward the constellation of the Fox (Vulpecula). It takes light about 1000 years to reach us from M27, featured here in colors enhanced by red for hydrogen and blue for oxygen. We now know that in about 6 billion years, our Sun will shed its outer gases into a planetary nebula like M27, while its remaining center will become an X-ray hot white dwarf star. Understanding the physics and significance of M27 was well beyond 18th century science, though. Even today, many things remain mysterious about planetary nebulas, including how their intricate shapes are created.

Photo by Francesco Antonucci

NASA Astronomy Picture of the Day:

What if you could see the entire sky -- all at once -- for an entire year? That, very nearly, is what is pictured here. Every 15 seconds during 2025, an all-sky camera took an image of the sky over the Netherlands. Central columns from these images were then aligned and combined to create the featured keogram, with January at the top, December at the bottom, and the middle of the night running vertically just left of center. What do we see? Most obviously, the daytime sky is mostly blue, while the nighttime sky is mostly black. The twelve light bands crossing the night sky are caused by the glow of the Moon. The thinnest part of the black hourglass shape occurs during the summer solstice, like today, when days are the longest, while the thickest part occurs at the winter solstice. Equinoxes can also be located in the keogram, for example the northern-spring equinox from one year ago is about three-quarters of the way up.

NASA Astronomy Picture of the Day:

Venus is now appearing on the celestial stage as Earth's brilliant evening star, performing with the Moon, other wandering planets, and bright stars in western skies. For evening sky gazers on June 17, the celestial beacon rose after sunset close by a young, slender, crescent Moon. But from some locations the Moon could be seen to occult or pass in front of Venus. And from a backyard observatory in southern British Columbia, Canada, the lunar occultation was played out in daylight. This stunning telescopic snapshot captured a scene in dramatically cloudy skies, following Venus' hour long disappearance, as the evening star emerged beyond the bright lunar limb.

Photo by Debra Ceravolo

NASA Astronomy Picture of the Day:

Does this scene look familiar? It is a modern recreation of the famous painting Starry Night by Vincent van Gogh. Both the image and the painting depict a tall tree on the left, a crescent moon on the upper right, the planet Venus just to the right of the tree, a foreground horizon rising from left to right, and clouds above the horizon. Differences include that the photograph was taken in mid-April earlier this year in Cascavel, Brazil, while the painting was composed in Saint-Rémy-de-Provence, France, in 1889. The original Starry Night is considered by many to be one of the three most famous paintings in the world today and a statement about the wonders of the night sky. Today is (roughly) the anniversary of the morning that van Gogh saw the sky that he later painted in his version of Starry Night. Night Sky Jigsaw: Astronomy Puzzle of the Day

Photo by Rodrigo Guerra, Original Painting: Vincent van Gogh

NASA Astronomy Picture of the Day:

Do you see that blue blob to the lower right of the image center? Astronomers think that it shows where a massive star exploded as a supernova whose light reached Earth 1,700 years ago. The image combines optical data from the PanSTARRS telescopes in Hawaii (background stars in red, green, and blue), radio from the MeerKAT telescope in South Africa (large red cloud) and X-rays from NASA's Chandra X-ray Observatory and ESA’s XMM-Newton (shown in blue). The large cloud is a star forming region called Sagittarius C, which is approximately 50 light-years in extent and about 26,000 light-years from Earth. It is located only about 260 light-years from the supermassive black hole in the center of the Galaxy (off to the left of the image). If the blue blob is confirmed to be a supernova remnant, it would be one of the closest ever discovered to the Galactic Center. In this dense region, the deaths of massive stars are connected to the birth of new stars through gas and magnetic fields in a complex way.

Photo by X-ray: NASA/CXC/UCLA/Z. Zhu et al.; ESA/XMM-Newton; Optical: PanSTARRS; Radio: MeerKAT; Image Processing: NASA/CXC/SAO/L. Frattare and P. Edmonds Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II)

NASA Astronomy Picture of the Day:

How did a hamster wheel get into space? The Hamster Wheel Nebula (Longmore 8) was discovered by Andrew Longmore in 1976 as a part of a larger survey of the southern sky. This survey employed several improvements in photographic technology, including the use of highly sensitive film, to capture deeper and fainter objects on plates that were examined by eye and catalogued. The featured image, taken at Observatorio El Sauce in Chile, depicts an intricate wheel structure of glowing hydrogen that was thrown out into space by a dying star and ionized by the leftover white dwarf. This structure was barely visible on the original plate, emphasizing the power of modern telescopes and cameras. Two opposing clumps of red hydrogen gas encased in the blue veil of ionized oxygen hint at the presence of a companion to the bright white dwarf at the wheel’s center!

Photo by Mazlin, Parker, Forman, Magill, Hanson Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II)

NASA Astronomy Picture of the Day:

While cruising around Saturn, be on the lookout for picturesque arrangements of moons, rings, and shadows. One such striking sight occurred in 2005 and was captured by the then Saturn-orbiting Cassini spacecraft. In the featured image, moons Mimas (left) and Tethys (right) are visible on either side of Saturn's thin rings, which are seen nearly edge-on. Across the top of Saturn are dark shadows of the wide rings, exhibiting their impressive complexity. The violet-light image brings up the texture of the backdrop: Saturn's clouds. Cassini orbited Saturn from 2004 until mid-2017, when the robotic spacecraft was directed to dive into Saturn to keep it from contaminating any moons. Explore the Universe: Random APOD Generator