Αστρονομική Εικόνα της Ημέρας από τη NASA

Προηγούμενες Αστρονομικές Εικόνες της Ημέρας από τη NASA

Anticrepuscular Rays over Sicily

25/06/2026

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.

M27: The Dumbbell Nebula

22/06/2026

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.

Starry Night II

19/06/2026

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

Longmore 8: The Hamster Wheel Nebula

17/06/2026

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!

Moons, Rings, Shadows, Clouds: Saturn (Cassini)

16/06/2026

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

Triple Shockwave from Sun Crossing Rocket

15/06/2026

What's happening to this Sun-crossing rocket? The SpaceX Falcon 9 rocket, visible on the upper left, launched only about one minute before this amazing image was captured. As it rose to low Earth orbit from Cape Canaveral, Florida, USA, in late May, the rocket became supersonic before it crossed the disk of the distant Sun -- from the perspective of the well-placed photographer. The spacecraft's high speed caused bow-shaped compressed-air shockwaves to form across leading surfaces, with at least three visible even outside the Sun's disk because they refract sunlight. The trailing exhaust caused turbulence visible on the lower right. None of this was damaging to the robotic Starlink 10-53 mission, which delivered 29 communications satellites to low Earth orbit as planned. And if that isn't amazing enough - the Sun had spots! Sky Surprise: What picture did APOD feature on your birthday? (after 1995)

10 Days of Venus and Jupiter

14/06/2026

Venus and Jupiter may have caught your attention lately. The recent close conjunction of the two brightest planets in recent evening skies has been hard to miss. With Jupiter at the top, starting on May 30 and ending on June 8, their close approach was chronicled daily, left to right, in the featured panels from Maharashtra, India. Near the western horizon, the evening sky colors and exposures used for each panel depend on the local conditions near sunset. At their closest on June 9, the celestial pair appeared to be only about three times the width of a full moon apart. Of course, on that date, the two planets were physically separated by over 600 million kilometers in their orbits around the Sun. In the coming days, Jupiter will slowly settle into the sunset glare, but Venus will continue to move farther from the Sun in the western sky to excel in its current role as the brilliant evening star. Gallery: Venus - Jupiter Conjunction of 2026 June

Interplanetary Earth

13/06/2026

In an interplanetary first, on July 19, 2013 Earth was photographed on the same day from two other worlds of the Solar System, innermost planet Mercury and ringed gas giant Saturn. Pictured on the left, Earth is the pale blue dot just below the rings of Saturn, as captured by the robotic Cassini spacecraft then orbiting the outermost gas giant. On that same day people across planet Earth snapped many of their own pictures of Saturn. On the right, the Earth-Moon system is seen against the dark background of space as captured by the sunward MESSENGER spacecraft, then in Mercury orbit. MESSENGER took its image as part of a search for small natural satellites of Mercury, moons that would be expected to be quite dim. In the MESSENGER image, the brighter Earth and Moon are both overexposed and shine brightly with reflected sunlight. Destined not to return to their home world, both Cassini and MESSENGER have since retired from their missions of Solar System exploration.

Η Αστρονομική Εικόνα της Ημέρας από τη NASA

Buck Moon and Belt of Venus

01/08/2026