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Explanation: Spooky shapes seem to haunt this dusty expanse, drifting through the night in the royal constellation Cepheus. Of course, the shapes are cosmic dust clouds visible in dimly reflected starlight. Far from your own neighborhood, they lurk above the plane of the Milky Way at the edge of the Cepheus Flare molecular cloud complex some 1,200 light-years away. Over 2 light-years across and brighter than most of the other ghostly apparitions, vdB 141 or Sh2-136 is also known as the Ghost Nebula. It lies at lower right in the starry field of view. Inside the Ghost Nebula are reddish...

Explanation: That's no moon. But you could be forgiven for thinking it was a crescent Moon in the sky. It is a lesser known fact that Venus also has phases. (What about other planets?) The featured image shows Venus seen almost directly between the Sun and the Earth. This happens once every year and a half, and it is like the alignment that happens every month during a new Moon. But the new Moon is dark, while Venus' backlit atmosphere refracts and scatters the sunlight, creating a glowing crescent arc that extends beyond 180 degrees: the tips of this arc...

Explanation: Jupiter is one of the least lonely planets in the Solar System, at least when it comes to natural satellites. 115 moons have been discovered orbiting Jupiter so far! (Saturn has the most with 293, but who’s counting.) Ganymede and Io, two of Jupiter’s Galilean moons, met in the sky on October 20th, 2026. Today’s video captures the meeting, with Ganymede briefly blocking Io from view. This event, when an astronomical object passes in front of another and either completely or partially blocks it, is called a mutual occultation. The mutual occultations of Galilean moons are rare to witness...

Explanation: Sometimes it's night on the ground but day in the air. As the Earth rotates to eclipse the Sun, sunset rises up from the ground. Therefore, at sunset on the ground, sunlight still shines on clouds above. Under usual circumstances, a pretty sunset might be visible, but unusual noctilucent clouds float so high up they can be seen well after dark. Normally too dim to be seen, they may become visible just after sunset during the summer when illuminated by sunlight from below the horizon. Noctilucent clouds are the highest clouds and are known more technically as polar mesospheric...

Explanation: The Great Nebula in Orion, an immense, nearby starbirth region, is one of 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 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...

Explanation: Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters so fast, why gravitational lenses so strongly deflect light, and how visible matter is distributed. The featured image from the American Museum of Natural History's Hayden Planetarium Space Show, Dark Universe, highlights one example of how pervasive dark matter might haunt our universe. In this frame from a detailed computer simulation, complex filaments of dark matter, shown in black, are strewn about the universe like...

Explanation: This Rosetta spacecraft selfie was snapped on October 7th, 2014. At the time the comet-chasing spacecraft was about 472 million kilometers from planet Earth, but only 16 kilometers from the surface of comet 67P/Churyumov-Gerasimenko. Looming beyond the spacecraft near the top of the frame, dust and gas stream away from the comet's curious double-lobed nucleus. Bright sunlight glints off one of Rosetta's 14 meter long solar arrays. In fact, two exposures, one short and one long, were combined to record the dramatic high contrast scene using the CIVA camera system on Rosetta's still-attached Philae lander. Its chosen primary landing...

Explanation: Looking toward the north from Mullion, New South Wales, Australia, the Andromeda Galaxy never gets more than a few degrees above the horizon. During the southern hemisphere spring, Andromeda is highest in the sky around midnight though. And in this telephoto scene from October 10/11, multiple exposures were used to reveal the spiral galaxy in tantalizing detail as it climbed above rolling Australian hills. Also known as M31, the Andromeda Galaxy is one of the brightest objects in the Messier catalog, but is only visible to the unaided eye as a small, faint, fuzzy patch. Digitally tracked and stacked...

Explanation: Star light, star bright: is there a green star out tonight? Other than the Sun, all stars are so far from Earth that they appear as points in the sky. They are mostly white, but sometimes noticeably red or blue. This color typically relates to the temperature: blue stars are hotter than red stars. What about other colors? The featured image is an illustration showing WD J1330+6435, a white dwarf star, surrounded by an accretion disk with gas and rocks orbiting the star. White dwarfs are small, faint stars that are left over when a star like the Sun...

Explanation: Jinkies, look at all those ghosts! It took 100 hours of observation and a special oxygen filter for today’s image to capture three faint nebulas hidden in the Cassiopeia constellation. IC 59 and IC 63, the original Ghosts of Cassiopeia, haunt the region near multi-star system γ Cassiopeia. Energetic light from γ Cassiopeia causes the hydrogen gas in IC 59 and 63 to glow red. Their dust reflects and scatters some blue-ish white starlight. Newly discovered Objects 1, 2, and 3 appear as blue phantoms, revealing the presence of ionized oxygen. But ionized by what? Like at the bow...

Explanation: This is an unusual rainbow. For one thing, the rainbow is not complete, appearing only in a sunlit fan -- but that by itself is not very unusual. What is most unusual is the fake location of the Sun. The Sun appears to be toward the front, just below those hills -- but it is not. That is not how rainbows work. Rainbows involve a backward reflection from falling rain, so that the Sun must really be behind you. In this case, gaps between clouds near the setting Sun allowed rays to cross the entire sky and appear to...

Explanation: Explanation : What is Treble Clef? This unusual radio structure extends over 2 million light-years and resembles a common musical symbol -- but has its visible light hidden by our own Milky Way Galaxy. Examined in 2004, the nature of VLSS J0318.9+5755, dubbed Treble Clef, remained unknown. Recent observations by the Chandra X-ray Observatory and eROSITA, however, have led to the hypothesis that the Treble Clef central cloud of charged particles was originally expelled by a supermassive black hole at the center of a galaxy. After the radio emission from those particles faded, they may have been reinvigorated by...

Explanation: Yes, but have you ever experienced the Eagle Nebula with your ears? The famous nebula M16 is best known for the feast it gives your eyes, highlighting bright young stars forming deep inside dark towering structures. These light-years long columns of cold gas and dust are some 6,500 light-years distant toward the constellation of the Serpent (Serpens). Sculpted and eroded by the energetic ultraviolet light and powerful winds from M16's cluster of massive stars, the cosmic pillars themselves are destined for destruction. But the turbulent environment of star formation within M16, whose spectacular details are captured in this combined...

Explanation: Put on your red/blue glasses and float next to the jagged and double-lobed nucleus of Churyumov-Gerasimenko, also known as Comet 67P . The stereo anaglyph was created by combining two images from the Rosetta spacecraft's narrow angle OSIRIS camera taken on July 25, 2015 from a distance of 184 kilometers. Numerous jets are emanating from the small solar system world's active surface near its closest approach to the Sun. The larger lobe is around 4 kilometers in diameter, joined to a smaller, 2.5 kilometer diameter lobe by a narrow neck. Rosetta's mission to the comet ended in September 2016...

Explanation: Blasting into the predawn sky on Tuesday, October 13, a Falcon 9 rocket and Dragon spacecraft are headed for low Earth orbit in this stunning timelapse video captured from Indian Harbour Beach, Florida. Starting with a launch from Space Launch Complex 40 at Cape Canaveral Space Force Station, Falcon and Dragon are chasing the International Space Station on NASA's 35th Commercial Resupply Services mission. On cue, the space station itself enters the frame from the top. Almost 8 seconds into the 30 second timelapse. the bright streak of the ISS appears heading "down" toward the horizon. The first and...

Explanation: The city lights outshine the stars in the City That Never Sleeps. Who would have thought that the Milky Way could be visible in this sky? This image was taken with a filter that blocks most visible light, capturing instead only light in the near-infrared region of the electromagnetic spectrum (with lower energy than visible light). The astrophotographer's clever setup blocks most of the light pollution from the city: old incandescent light bulbs and some neon lights are still bright in the near-infrared, but fluorescent and LED light bulbs are not. Of course, stars are also bright in the...

Explanation: What a cosmic coincidence! In today’s image, Mars joins the Beehive cluster (M44 or Praesepe) below an auroral curtain and above a horizon of happy little trees near Lansjärv, Sweden. An eruption off the Sun reached Earth on October 10th, 2026 causing strong disturbances in Earth’s magnetic field. Energetic particles from the eruption collide with and energize the molecules in Earth’s atmosphere, which release that extra energy as the colorful aurora captured here. Auroras, or guovssahasat in North Sámi, is traditionally viewed with respect by the Sámi people indigenous to Sweden and other Arctic regions. Coincidentally, Mars appeared closest...

Explanation: This stairway in Chile brings you only a little bit closer to heaven. But ooh, the sky above it makes you wonder. For example, you may wonder about the dark lane of our own Milky Way galaxy rising behind the expansive Atacama Desert in Chile, the band of zodiacal light on the upper left, the green and red airglow just above the horizon, the star Spica in the zodiacal light stripe, and, at the very top on the right, the Small Magellanic Cloud galaxy. The Desert Staircase sculpture is in the foreground, and this image was timed to catch...

Explanation: How many moons can you see? The best answer is five: four orbiting Jupiter and Luna orbiting Earth. This multi-moon picture was possible because Earth's Moon moved directly in front of Jupiter last week. The featured image is a series of exposures near alignment taken from Westchester, New York, USA. The sunlit crescent of Earth's Moon, on the lower left, is overexposed, while the Moon's night side, on the upper right, is faintly illuminated by Earthshine. Lined up nearly vertically above our Moon, listed from bottom to top, are Jupiter's bright Galilean satellites: Ganymede, Io, Callisto, and Europa. Callisto,...

Explanation: Scientists are melting holes in the bottom of the world. In fact, almost 100 holes melted near the South Pole are now being used as an astronomical observatory. Astronomers with the IceCube Neutrino Observatory lowered a long string knotted with basketball-sized light detectors into each vertical lake. The water in each hole soon refreezes. The detectors attached to the strings are sensitive to blue light emitted in the surrounding clear ice. Such light results from fast-moving secondary particles liberated when high-energy neutrinos emitted by powerful processes out in the universe collide with ice molecules. IceCube has now detected many...