
"I want to know why the universe exist, why there is something greater than nothing."

Steven Hawking
Scientist, Space Lover

What would it be like to visit the Moon? The first major fictional cinematic film exploring this enduring transcultural fantasy was titled Le voyage dans la lune (A Trip to the Moon) and made in 1902, becoming one of the most popular movies of the early years of the twentieth century. The silent film starred the filmmaker Georges Melies himself and portrayed a club of astronomers voyaging to the Moon and back. Pictured above is a frame from the movie that has become an enduring icon for both film and space. Alluding to a bullseye trajectory, the Man in the Moon is caricatured as being struck by the human-built spaceship. The entire 14-minute film is now freely available. Visiting the Moon remained a very popular topic even 67 years later in 1969 when humans first made an actual voyage.
What does the Milky Way look like in radio waves? To better find out, GLEAM surveyed the central band of our galaxy in high resolution radio light as imaged by the Murchison Widefield Array in Australia. As the featured video slowly scrolls, radio light (71 - 231 MHz) is seen on the left and visible light -- from the same field -- on the right. Differences are so great because most objects glow differently in radio and visible light, and because visible light is stopped by nearby interstellar dust. These differences are particularly apparent in the direction toward the center of our galaxy, seen about a third of the way through. Among the many features that appear in the radio, bright red patches are usually supernova remnants of exploded stars, while areas colored blue are stellar nurseries filled with bright young stars. Did you know: APOD is available from numerous sites, including social media?

What if you could see out to the edge of the observable universe? You would see galaxies, galaxies, galaxies, and then, well, quasars, which are the bright centers of distant galaxies. To expand understanding of the very largest scales that humanity can see, a map of the galaxies and quasars found by the Sloan Digital Sky Survey from 2000 to 2020 -- out to near the edge of the observable universe -- has been composed. Featured here, one wedge from this survey encompasses about 200,000 galaxies and quasars out beyond a look-back time of 12 billion years and cosmological redshift 5. Almost every dot in the nearby lower part of the illustration represents a galaxy, with redness indicating increasing redshift and distance. Similarly, almost every dot on the upper part represents a distant quasar, with blue-shaded dots being closer than red. Clearly shown among many discoveries, gravity between galaxies has caused the nearby universe to condense and become increasingly more filamentary than the distant universe. More Detailed Maps: Related to Today's APOD