ePrivacy and GPDR Cookie Consent by Cookie Consent

Η Αστρονομική Εικόνα της Ημέρας από τη NASA

Long Shadows of the Montes Caucasus

Long Shadows of the Montes Caucasus

19/12/2025

When the Moon is at its first quarter phase, the Sun rises along the Montes Caucasus as seen from the lunar surface. The lunar mountain range casts the magnificent, spire-like shadows in this telescopic view from planet Earth, looking along the lunar terminator or the boundary between lunar night and day. Named for Earth's own Caucasus Mountains, the rugged lunar Montes Caucasus peaks, up to 6 kilometers high, are located between the smooth Mare Imbrium to the west and Mare Serenitatis to the east. Still mostly in shadow in this first quarter lunarscape, at the left (west) impact craters reflect the light of the rising Sun along their outer, eastern crater walls.

Copyright: When the Moon

Προηγούμενες Αστρονομικές Εικόνες της Ημέρας από τη NASA

Comet Tsuchinshan-Atlas over the Dolomites

Comet Tsuchinshan-Atlas over the Dolomites

06/11/2024

Comet Tsuchinshan-Atlas is now headed back to the outer Solar System. The massive dusty snowball put on quite a show during its trip near the Sun, resulting in many impressive pictures from planet Earth during October. The featured image was taken in mid-October and shows a defining visual feature of the comet -- its impressive anti-tail. The image captures Comet C/2023 A3 (Tsuchinshan–ATLAS) with impressively long dust and ion tails pointing up and away from the Sun, while the strong anti-tail -- composed of more massive dust particles -- trails the comet and points down and (nearly) toward the recently-set Sun. In the foreground is village of Tai di Cadore, Italy, with the tremendous Dolomite Mountains in the background. Another comet, C/2024 S1 (ATLAS), once a candidate to rival Comet Tsuchinshan-Atlas in brightness, broke up last week during its close approach to our Sun. Growing Gallery: Comet Tsuchinshan-ATLAS in 2024

Copyright: Alessandra Masi

Milky Way over Easter Island

Milky Way over Easter Island

05/11/2024

Why were the statues on Easter Island built? No one is sure. What is sure is that over 900 large stone statues called moais exist there. The Rapa Nui (Easter Island) moais stand, on average, over twice as tall as a person and have over 200 times as much mass. It is thought that the unusual statues were created about 600 years ago in the images of local leaders of a vibrant and ancient civilization. Rapa Nui has been declared by UNESCO to a World Heritage Site. Pictured here, some of the stone giants were imaged last month under the central band of our Milky Way galaxy. Previously unknown moais are still being discovered. Alternative Multi-APOD Front Page: MyUniverseHub.com

Copyright: Josh Dury

M42: The Great Nebula in Orion

M42: The Great Nebula in Orion

04/11/2024

The Great Nebula in Orion, an immense, nearby starbirth region, is probably the most famous of all astronomical nebulas. Here, glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1500 light-years away. In the featured deep image in assigned colors highlighted by emission in oxygen and hydrogen, wisps and sheets of dust and gas are particularly evident. The Great Nebula in Orion can be found with the unaided eye near the easily identifiable belt of three stars in the popular constellation Orion. In addition to housing a bright open cluster of stars known as the Trapezium, the Orion Nebula contains many stellar nurseries. These nurseries contain much hydrogen gas, hot young stars, proplyds, and stellar jets spewing material at high speeds. Also known as M42, the Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun.

Copyright: Fényes Lóránd

Jupiter Abyss

Jupiter Abyss

03/11/2024

What's that black spot on Jupiter? No one is sure. During one pass of NASA's Juno over Jupiter, the robotic spacecraft imaged an usually dark cloud feature informally dubbed the Abyss. Surrounding cloud patterns show the Abyss to be at the center of a vortex. Since dark features on Jupiter's atmosphere tend to run deeper than light features, the Abyss may really be the deep hole that it appears -- but without more evidence that remains conjecture. The Abyss is surrounded by a complex of meandering clouds and other swirling storm systems, some of which are topped by light colored, high-altitude clouds. The featured image was captured in 2019 while Juno passed only about 15,000 kilometers above Jupiter's cloud tops. The next close pass of Juno near Jupiter will be in about three weeks.

Copyright: NASA

Saturn at Night

Saturn at Night

02/11/2024

Saturn is bright in Earth's night skies. Telescopic views of the outer gas giant planet and its beautiful rings often make it a star at star parties. But this stunning view of Saturn's rings and night side just isn't possible from telescopes in the vicinity of planet Earth. Peering out from the inner Solar System they can only bring Saturn's day side into view. In fact, this image of Saturn's slender sunlit crescent with night's shadow cast across its broad and complex ring system was captured by the Cassini spacecraft. A robot spacecraft from planet Earth, Cassini called Saturn orbit home for 13 years before it was directed to dive into the atmosphere of the gas giant on September 15, 2017. This magnificent mosaic is composed of frames recorded by Cassini's wide-angle camera only two days before its grand final plunge. Saturn's night will not be seen again until another spaceship from Earth calls.

Copyright: NASA

Spiral Galaxy NGC 6744

Spiral Galaxy NGC 6744

01/11/2024

Big, beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across, larger than our own Milky Way. It lies some 30 million light-years distant in the southern constellation Pavo but appears as only a faint smudge in the eyepiece of a small telescope. We see the disk of the nearby island universe tilted towards our line of sight in this remarkably deep and detailed galaxy portrait, a telescopic image that spans an area about the angular size of a full moon. In it, the giant galaxy's elongated yellowish core is dominated by the light from old, cool stars. Beyond the core, grand spiral arms are filled with young blue star clusters and speckled with pinkish star forming regions. An extended arm sweeps past smaller satellite galaxy NGC 6744A at the upper left. NGC 6744's galactic companion is reminiscent of the Milky Way's satellite galaxy the Large Magellanic Cloud.

Copyright: John Hayes

Rigel and the Witch Head Nebula

Rigel and the Witch Head Nebula

31/10/2024

By starlight, this eerie visage shines in the dark with a crooked profile evoking its popular name, the Witch Head Nebula. In fact, this entrancing telescopic portrait gives the impression that a witch has fixed her gaze on Orion's bright supergiant star Rigel. More formally known as IC 2118, the Witch Head Nebula spans about 50 light-years and is composed of interstellar dust grains reflecting Rigel's starlight. The color of the Witch Head Nebula is caused not only by Rigel's intense blue light, but because the dust grains scatter blue light more efficiently than red. The same physical process causes Earth's daytime sky to appear blue, although the scatterers in Earth's atmosphere are molecules of nitrogen and oxygen. Rigel and this dusty cosmic crone are about 800 light-years away. You may still see a few witches in your neighborhood tonight though, so have a safe and Happy Halloween!

Copyright: Simone Curzi

NGC 7635: The Bubble Nebula

NGC 7635: The Bubble Nebula

30/10/2024

What created this huge space bubble? Blown by the wind from a star, this tantalizing, head-like apparition is cataloged as NGC 7635, but known simply as the Bubble Nebula. The featured striking view utilizes a long exposure to reveal the intricate details of this cosmic bubble and its environment. Although it looks delicate, the 10 light-year diameter bubble offers evidence of violent processes at work. Seen here above and right of the Bubble's center, a bright hot star is embedded in the nebula's reflecting dust. A fierce stellar wind and intense radiation from the star, which likely has a mass 10 to 20 times that of the Sun, has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The intriguing Bubble Nebula lies a mere 11,000 light-years away toward the boastful constellation Cassiopeia. Your Sky Surprise: What picture did APOD feature on your birthday? (post 1995)

Copyright: Chad Leader

Η Αστρονομική Εικόνα της Ημέρας από τη NASA (NASA Astronomy Picture of the Day) είναι μια δωρεάν υπηρεσία που παρέχει καθημερινά μια εντυπωσιακή εικόνα από το σύμπαν, την λήψη της οποίας έχει πραγματοποιήσει κάποιος από τους αστρονόμους της NASA ή από κάποιον από τους δορυφόρους ή τα τηλεσκόπια που η NASA λειτουργεί. Οι εικόνες που εμφανίζονται καλύπτουν μια ευρεία γκάμα από θέματα, συμπεριλαμβανομένων των αστερισμών, των γαλαξιών, των πλανητικών συστημάτων, των κομητών, των αστρικών σωμάτων και των παρατηρητηρίων. Κάθε εικόνα συνοδεύεται από μια σύντομη εξήγηση και πληροφορίες σχετικά με το τι παρατηρείται στην εικόνα.