Αστρονομική Εικόνα της Ημέρας από τη NASA

Προηγούμενες Αστρονομικές Εικόνες της Ημέρας από τη NASA

Hello World

04/04/2026

From pole to pole our fair planet is captured in this snapshot from space, an evocative image from a window of the Orion spacecraft Integrity. From the spacecraft's perspective the Sun is moving behind Earth's bright limb along the lower right. Africa and the Iberian peninsula are in view on the pale blue planet's surface, while aurorae crown Earth's south and north poles at top right and bottom left. Commander Reid Wiseman took the historic picture on Artemis II mission flight day 2 (April 2), after the completion of the planned translunar injection burn. That burn boosted the spacecraft out of Earth orbit, sending Integrity and crew on a trajectory that will take them around the Moon and back again. That's a journey humans last made over 50 years ago.

Caught in the Web: Visualization of a Black Hole Merger in the Tarantula Nebula

03/04/2026

How can we see what is invisible? Black holes are not easy to see in the dark cosmic night, but astronomers can find them by analyzing their gravitational effects on matter, light and spacetime. The featured image shows an illustration that combines a simulation of a black hole binary system in its final "death-dance" with an astrophotography image of the Tarantula Nebula in the background. Even though black holes don't emit light, they distort the path of light rays, acting like a gravitational lens. As a result, the nebula appears extremely distorted, forming Einstein rings and multiple images. Tarantula Nebula lies in the Large Magellanic Cloud, a dwarf galaxy that is one of the satellite galaxies of the Milky Way, 160,000 light-years away. That is more than 1,000 times closer than any of the binary black hole mergers detected so far. We'll probably never detect a merger so close to home!

Liftoff! Returning to the Moon

02/04/2026

We are one small step closer to returning to the Moon. A new chapter in human exploration began yesterday when NASA's Artemis II launched aboard the Space Launch System (SLS) from Kennedy Space Center. Carrying four astronauts, the Orion spacecraft's planned lunar flyby will be the first in over half a century. This historic test flight, echoing the legacy of Apollo while pushing beyond it, will carry its crew farther from Earth than any humans since 1972, looping around the Moon before returning home. During the approximately ten-day journey, Orion's systems--from life support to navigation--will be tested in deep space, while astronauts observe the lunar surface, including shadowed regions of the far side rarely seen with such perspective. After looping around the Moon, the astronauts will return to Earth, ending their journey with a Pacific Ocean splashdown.

The Claw and Bubble Nebulae

01/04/2026

What unexpected things do you see when you look up at the night sky? Today’s image resembles an abstract painting, with large swaths of color strewn across a cosmic canvas seemingly without design. Despite the image's abstract nature, the human mind finds patterns, identifying a large claw reaching up towards a floating bubble. Embedded within these seemingly random structures are the physical laws that govern how light and matter interact. The Claw (Sh2-157) and Bubble (NGC 7635) Nebulae glow colors that are mapped to the yellow and blue shown, indicating the presence of hydrogen and oxygen ionized by the intense light emitted from stars several times the mass of the Sun. This image depicts both the chaos and structure of astronomical processes, showing that a common thread between art and science is to look for the unexpected.

Uranus's Largest Moon: Titania

31/03/2026

Titania's tortured terrain is a mix of canyons, cliffs, and craters. NASA's interplanetary robot spacecraft Voyager 2 passed the largest moon of Uranus in 1986 and took the feature picture. That the trenches of Titania resemble those on another moon of Uranus, Ariel, indicate that Titania underwent some violent surface event possibly related to water freezing and expanding in its distant past. Although Titania is Uranus's largest moon, it is only about half the radius of Triton - the largest moon of Uranus's sister planet Neptune, which itself is slightly smaller than Earth's Moon. Titania, discovered by William Herschel in 1787, is essentially a large dirty iceball that is composed of about half water-ice and half rock. There is recent speculation that radioactive heating melts some underground ice into oceans.

Peculiar Elliptical Galaxy Centaurus A

30/03/2026

What's happened to the center of this galaxy? Dramatic dust lanes run across the center of unusual elliptical galaxy Centaurus A. These dust lanes are so thick they almost completely obscure the galaxy's center in visible light. This is particularly unusual as Cen A's older stars and oval shape are characteristic of a giant elliptical galaxy, a galaxy type typically low in dark dust. Pictured in this deep image is a complex network of foreground gas and dust, as well as shells of dim stars and a jet projecting to the upper right. Also known as NGC 5128, Cen A is surely the result of a galactic collision where many young dust-creating stars were formed. However, details of the creation of Cen A's unusually active center and iconic central dust lanes are still being researched. Cen A lies only 13 million light years away, making it the closest active galaxy. Jigsaw Galaxy: Astronomy Puzzle of the Day

Copyright: SADR Observatory Team: J-C Dalouzy, P. Bazart, M. Dherbécourt, C. Humbert, G. Leroy, J-P Quéau, H. Talbot, & E. Valin

A Message from Earth

29/03/2026

What are these Earthlings trying to tell us? The featured message was broadcast from Earth towards the globular star cluster M13 in 1974. During the dedication of an upgrade to the Arecibo Observatory - then the largest single radio telescope in the world - a string of 1's and 0's representing the diagram was sent. This attempt at extraterrestrial communication was mostly ceremonial - humanity regularly broadcasts radio and television signals out into space accidentally. Even were this message received, M13 is so far away we would have to wait almost 50,000 years to hear an answer. The featured message gives a few simple facts about humanity and its knowledge: from left to right are numbers from one to ten, atoms including hydrogen and carbon, some interesting molecules, DNA, a human with description, basics of our Solar System, and basics of the sending telescope. Several searches for extraterrestrial intelligence are currently underway. Explore the Universe: Random APOD Generator

Robert Goddard and Nell

28/03/2026

Robert H. Goddard, considered the father of modern rocketry, was born in Worcester Massachusetts in 1882. As a 16 year old, Goddard read H.G. Wells' science fiction classic "War Of The Worlds" and dreamed of space flight. By 1926 he had designed, built, and flown the world's first liquid fuel rocket. Launched 100 years ago, on March 16, 1926 from his aunt Effie's farm in Auburn Massachusetts, the rocket dubbed "Nell", rose to an altitude of 41 feet in a flight that lasted about 2 1/2 seconds. In this posed photo Goddard stands next to the 10 foot tall rocket, holding the launch stand frame. To achieve a stable flight without the need for fins, the rocket's heavy motor was located at the top, fed by lines from liquid oxygen and gasoline fuel tanks at the bottom. Widely recognized as a gifted experimenter and engineering genius, his rockets were many years ahead of their time. Goddard was awarded over 200 patents in rocket technology, most of them after his death in 1945. A liquid fuel rocket constructed on principles developed by Goddard landed humans on the Moon in 1969.

Η Αστρονομική Εικόνα της Ημέρας από τη NASA

The Retrograde Dance of Saturn and Neptune

06/05/2026