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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

A group of Dorcas gazelle at dusk in Morocco.

Anass Errihani, CC BY-SA 3.0, via Wikimedia Commons. View source.

By Hugues de BUYER-MIMEURE on Unsplash

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

State boundaries can be iconic. Many were drawn by human hands, but some of the most recognizable contours were shaped by nature: the boot of southeastern Louisiana, carved by the Mississippi River, or the ocean waves sculpting the hook of Cape Cod in Massachusetts. More at The Conversation➜

Chrysomma sinense (Yellow-eyed Babbler) in Bhigwan, Maharashtra, India.

Tisha Mukherjee, CC BY-SA 4.0, via Wikimedia Commons. View source.

By Loïc Fürhoff on Unsplash

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.

Bags of organic fertiliser adorn newly-planted fields against a backdrop of the Western Catchment in the Nilgiri mountains. Tamil Nadu, India.

Timothy A. Gonsalves, CC BY-SA 4.0, via Wikimedia Commons. View source.