Αστρονομική Εικόνα της Ημέρας από τη NASA

Προηγούμενες Αστρονομικές Εικόνες της Ημέρας από τη NASA

NanoSail-D2

02/01/2026

In 2011, on January 20, NASA's NanoSail-D2 unfurled a very thin and very reflective 10 square meter sail becoming the first solar sail spacecraft in low Earth orbit. Often considered the stuff of science fiction, sailing through space was suggested 400 years ago by astronomer Johannes Kepler, who had observed comet tails blown by the solar wind. But modern solar sail spacecraft designs, like NanoSail-D2, Japan's interplanetary spacecraft IKAROS, or the Planetary Society's Lightsail A, rely on the small but continuous pressure from sunlight itself for thrust. Glinting in the sunlight as it circled planet Earth, NanoSail-D2's solar sail was periodically bright and visible to the eye. These remarkably detailed images were captured by manually tracking the orbiting solar sail spacecraft with a small telescope.

Auroral Corona

01/01/2026

Cycle 25 solar maximum made 2025 a great year for aurora borealis (or aurora australis) on planet Earth. And the high level of solar activity should extend into 2026. So, while you're celebrating the arrival of the new year, check out this spectacular auroral display that erupted in starry night skies over Kirkjufell, Iceland. The awesome auroral corona, energetic curtains of light streaming from directly overhead, was witnessed during a strong geomagnetic storm triggered by intense solar activity near the March 2025 equinox. This northland and skyscape captures the evocative display in a 21 frame panoramic mosaic.

HH-222: The Waterfall Nebula

31/12/2025

What created the Waterfall Nebula? The origin is still being researched. The structure, officially designated Herbig-Haro 222, appears in the region of NGC 1999 in the Great Orion Molecular Cloud complex. The elongated gaseous stream stretches about ten light years but appears similar to a long waterfall on Earth. Recent observations indicate that HH-222 is likely a gigantic gaseous bow shock, similar to a wave of water caused by a fast-moving ship. The origin of this shock wave is thought to be a jet outflow from the multiple star system V380 Orionis off the lower left of the frame. Therefore, gas does not flow along the waterfall, but rather the entire structure moves toward the upper right. The Waterfall Nebula lies about 1,500 light years away toward the constellation of Orion. The featured image was captured earlier this month from El Sauce Observatory in Chile. Jigsaw Nebula: Astronomy Puzzle of the Day

An Artificial Comet

30/12/2025

Yes, but can your comet tail do this? No, and what you are seeing is not the tail of a comet. The picture features a cleverly overlayed time-lapse sequence of a group of satellites orbiting Earth together in June. Specifically, these are Starlink communications satellites in low Earth orbit reflecting back sunlight before sunrise to Inner Mongolia, China. Although the satellites appear to the human eye as points, the 20-second-long camera exposures caused them to appear as short streaks. Currently there are over 9000 Starlinks in orbit, with more being launched nearly every week. Other satellite constellations are also being planned. Explore the Universe: Random APOD Generator

M1: The Crab Nebula

29/12/2025

This is the mess that is left when a star explodes. The Crab Nebula, the result of a supernova seen in 1054 AD, is filled with mysterious filaments. The filaments are not only tremendously complex but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The featured image was taken by an amateur astronomer in Leesburg, Florida, USA over three nights last month. It was captured in three primary colors but with extra detail provided by specific emission by hydrogen gas. The Crab Nebula spans about 10 light years. In the Nebula's very center lies a pulsar: a neutron star as massive as the Sun but with only the size of a small town. The Crab Pulsar rotates about 30 times each second. Explore the Universe: Random APOD Generator

NGC 1898: Globular Cluster in the Large Magellanic Cloud

28/12/2025

Jewels don't shine this bright -- only stars do. And almost every spot in this jewel-box of an image from the Hubble Space Telescope is a star. Now, some stars are more red than our Sun, and some more blue -- but all of them are much farther away. Although it takes light about 8 minutes to reach Earth from the Sun, NGC 1898 is so far away that it takes light about 160,000 years to get here. This huge ball of stars, NGC 1898, is called a globular cluster and resides in the central bar of the Large Magellanic Cloud (LMC) -- a satellite galaxy of our Milky Way Galaxy. The featured multi-colored image includes light from the infrared to the ultraviolet and was taken to help determine if the stars of NGC 1898 all formed at the same time or at different times. There are increasing indications that most globular clusters formed stars in stages, and that, in particular, stars from NGC 1898 formed shortly after ancient encounters with the Small Magellanic Cloud (SMC) and our Milky Way Galaxy. Space Telescopes Live: Where are Hubble and Webb looking right now?

Apollo 17's Moonship

27/12/2025

Awkward and angular looking, Apollo 17's lunar module Challenger was designed for flight in the near vacuum of space. Digitally enhanced and reprocessed, this picture taken from Apollo 17's command module America shows Challenger's ascent stage in lunar orbit. Small reaction control thrusters are at the sides of the moonship with the bell of the ascent rocket engine underneath. The hatch that allowed access to the lunar surface is seen at the front, with a round radar antenna at the top. Mission commander Gene Cernan is clearly visible through the triangular window. This spaceship performed gracefully, landing on the Moon and returning the Apollo astronauts to the orbiting command module in December of 1972. So where is Challenger now? While its descent stage remains at the Apollo 17 landing site in the Taurus-Littrow valley, the ascent stage pictured was intentionally crashed nearby after being jettisoned from the command module prior to the astronauts' return to planet Earth.

3I/ATLAS Flyby

26/12/2025

Attention grabbing interstellar visitor 3I/ATLAS made its not-so-close flyby of our fair planet on December 19 at a distance of 1.8 astronomical units. That's about 900 light-seconds. Still, this deep exposure captures the comet from another star system as it gently swept across a faint background of stars in the constellation Leo about 4 days earlier, on the night of December 15. Though faint, colors emphasized in the image data, show off the comet's yellowish dust tail and bluish ion tail along with a greenish tinged coma. And even while scrutinized by arrays of telescopes and spacecraft from planet Earth, 3I ATLAS is headed out of the Solar System. It's presently moving outward along a hyperbolic trajectory at about 64 kilometers per second relative to the Sun, too fast to be bound the Sun's gravity.

Η Αστρονομική Εικόνα της Ημέρας από τη NASA

Full Moonlight

03/01/2026