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Explanation: The Southern Crown (Corona Australis) dazzles with young and ancient celestial jewels. The Corona Australis Cloud is a collage of reflection and emission nebulae on the left of today’s image. At 430 light years away, this cloud is one of the closest star-forming regions to Earth. It contains gas cool enough (-260 Celsius or -440 Fahrenheit) to collapse into protostars. Recently formed stars paint blue hues across the cloud as their light reflects off surrounding material. The waltz of the R Coronae Australis binary system stirs up the nebula NGC 6729. The younger of the pair ionizes nearby gas...

Explanation: Is this a fossilized turtle on Mars? No. Although resembling a large Earth tortoise, this is a layered rock outcrop on Mars that is estimated to span about 15 meters, making it much larger than turtles on Earth. NASA’s robotic Curiosity rover came across this unusual mound, dubbed Miraflores, last month during its 4922nd Martian day exploring Mars. The small butte may survive because it was somehow more resistant to erosion than surrounding rock. More recent wind has now covered its top with orange Martian sand. Below the top shell, many layers of stratified rock are visible, possibly indicating...

Explanation: What's happening in the Statue of Liberty nebula? Bright stars and interesting molecules are forming and being liberated. The complex nebula resides in the star forming region called RCW 57, and besides the iconic monument, to some looks like a flying superhero or a weeping angel. This re-assigned color image showcases dense knots of dark interstellar dust, fields of glowing hydrogen gas ionized by these stars, and great loops of gas expelled by dying stars. A detailed study of NGC 3576, also known as NGC 3582 and NGC 3584, uncovered at least 33 massive stars in the end stages...

Explanation: A flying saucer from outer space crash-landed in the Utah desert after being tracked by radar and chased by helicopters. The year was 2004, and no space aliens were involved. The saucer, pictured here, was the Genesis sample return capsule, part of a human-made robot Genesis spaceship launched in 2001 by NASA itself to study the Sun. The unexpectedly hard landing at over 300 kilometers per hour occurred because the parachutes did not open as planned. The Genesis mission had been orbiting the Sun collecting solar wind particles that are usually deflected away by Earth's magnetic field. Despite the...

Explanation: At sunset, an alignment of rainbow and mountain shadow was captured in this remarkable snapshot. The stunning view was recorded from a fire lookout on Smith Peak in the Plumas National Forest near Portola, California on July 13. Still, near sunset it's no accident that the majestic mountain shadow seems to point to the center of the graceful rainbow arc. Due to perspective and the long line of sight the mountain shadow naturally forms a tapering triangular shape, its apex positioned at the point opposite the Sun on the horizon. Following thunderstorms in the region, the rainbow arched across...

Explanation: Comet 10P/Tempel 2 orbits the Sun once every 5.4 years. Currently visible in binoculars or small telescopes toward the constellation Capricornus, the periodic comet is captured in this sharp telescopic image from July 11 sporting a bright nuclear region and pretty greenish coma. Remarkably, a thin dust trail, not a typical dust tail, is also seen extending both east and west of the Tempel 2 nucleus. Unlike a comet dust tail, which tends to temporarily fan out in a direction away from the Sun, this dust trail is due to the residual dust shed during many past orbits along...

Explanation: This sparkling, colorful gemstone is a spiral galaxy, NGC 300. It is one of the closest spiral galaxies to Earth, only about 6 million light-years away. But does it really look like this? Here is a more standard portrait of it. This unusual image combines the light from the stars and dust within the galaxy with the light from ionized clouds of interstellar gas shown in red (Sulphur), green (Hydrogen) and blue (Oxygen). Combining red and green light in different proportions makes yellow or orange light, most visible in the image. Light from other ionized gases is also at...

A groundbreaking mission that explored Pluto and distant solar system objects in unprecedented detail has awakened from its longest sleep ever — and it’s 5.9 billion miles (9.5 billion kilometers) from Earth. NASA’s New Horizons spacecraft went into a planned hibernation mode on August 7, 2025, and woke up on June 23 using commands stored on its main computer. The mission’s flight controllers at the Johns Hopkins University’s Applied Physics Laboratory in Laurel, Maryland, confirmed that New Horizons is in great shape and ready to transmit a stream of science data gathered during hibernation from its location in the region...

Explanation: Is there an angry Sith using force lightning in the Tatacoa Desert? This is not science fiction, but a red sprite with multiple streamers! Ordinary lightning occurs when thundercloud particles collide, lose their electrons, and build up negative charge at the cloud bottom. The cloud’s negative charge repels negative charge deeper into the Earth, leaving Earth’s surface positively charged. The opposite charges attract, reaching towards each other and superheating the air into a white strike of plasma. Red sprites are millisecond events triggered by positive cloud-to-ground lightning. They extend up into the mesosphere where the air is too thin...

Ancient mathematical texts discovered at the Maya city of Xultun in Guatemala have revealed the name of a Maya astronomer for the first time, offering rare evidence of the scholars behind one of the ancient world’s most advanced systems of mathematics and astronomy. Researchers reconstructed and transcribed dozens of tiny inscriptions found on the plaster walls of a small building at the site. Their work uncovered a unique mathematical formula and identified its author, marking the first known case of a Classic Maya mathematician-astronomer being directly credited for his work. The findings were published in the journal Antiquity. Wall writings...

From the web: SpaceX is targeting Thursday, July 16, 2026, for the 13th test flight of its Starship megarocket. The 90-minute launch window opens at 6:45 p.m. EDT (5:45 p.m. CT / 22:45 GMT) at the company's Starbase facility in Boca Chica, Texas. Launch Details & Objectives: Mission: Starship Flight 13Vehicle: Version 3 (V3) Starship Key Milestone: The test flight aims to test fixes to anomalies from the previous flight and will attempt to deploy the first batch of upgraded Starlink Version 3 satellites. Viewing: SpaceX will host a live webcast of the flight test beginning about 30 minutes before...

The space between stars just got a little sweeter. Astronomers have detected a type of sugar in space that's also found in raspberries and self-tanners. The sugar, called erythrulose, lurks in what's called the interstellar medium: thin clouds of gas and dust littered between stars. Sugar does more than sweeten tea and powder doughnuts. Different varieties fuel our cells and even make up DNA. Scientists are itching to know how sugars form because they're a key ingredient for life as we know it. Using two dish-shaped radio telescopes in Spain, researchers collected data from a large gas cloud near the...

Explanation: Why is this asteroid a double? Earlier this month the Japanese robotic spacecraft Hayabusa2 shot past asteroid 98943 Torifune and captured pictures. Although previous observations from distant Earth indicated that Torifune was oblong, Hayabusa2 found that Torifune actually has two joined lobes. With a length of about four soccer fields, this space rock frequently comes near the Earth as it orbits the Sun, although it is not a threat. Besides the two lobes, Torifune shows many large boulders, but, surprisingly, no obvious craters, likely because its surface is a pile of rubble. Like asteroid Arrokoth, it appears that each...

Explanation: What do auroras look like from above? Behold! From the ground, auroras dance high above clouds, frequently causing spectacular displays. From space, they look a bit different. As the International Space Station (ISS) circles the Earth every 90 minutes, it sometimes sees auroras below that are active on the night side. A one-hour time-lapse video showing auroras from above was captured about two weeks ago from the orbiting ISS. The ISS -- and all objects in low Earth orbit -- will pass well above green auroras but just a bit above red glowing auroras. The auroras' electron and proton...

A detailed view of Halley's Comet in the Bayeux Tapestry. Image credit: Unknown author via Wikimedia Commons (public domain) ============================================================================ The Bayeux Tapestry is one of the most famous textile works in the world, and for the first time in more than 900 years it has returned to England to be exhibited at the British Museum. The work of art depicts the events leading up to the Battle of Hastings of 1066 and the Norman conquest of England. It also depicts an important astronomical event, the return of Halley’s comet. Although not in the right place. First of all, despite...

Satellites don't always stay in orbit. As they get closer to Earth, atmospheric drag can pull them lower and lower until they burn up, with solar activity speeding up the process. NASA's Swift Space Observatory is facing that fate -- its orbit is decaying, and if left alone, it will be destroyed in a matter of months. But in a first-of-its-kind mission, Katalyst Space, a startup, is teaming up with NASA to try and rescue Swift using the company's newly developed robotic spacecraft, LINK. "This is a historic mission, you know, some would call it the first of its kind,...

NASA is racing to save an aging telescope from falling back to Earth with a daring rescue mission. The $30 million salvage operation gets underway as soon as this week with the planned launch of a robotic lifesaver. NASA hired startup Katalyst Space Technologies to boost the Swift Observatory to a higher orbit where it can continue hunting for some of the universe’s biggest explosions. A three-armed spacecraft built by Katalyst will chase after Swift once it takes off from an atoll in the Pacific’s Marshall Islands aboard an airplane-launched Pegasus rocket. Liftoff could occur as early as Tuesday. Scanning...

"A robotic spacecraft built in nine months by Arizona-based startup Katalyst Space Technologies is set to launch no earlier than Tuesday, June 30, from Kwajalein Atoll in the Marshall Islands on a first-of-its-kind mission to grab NASA's sinking Neil Gehrels Swift Observatory and push it back to a safe orbit — the first time any commercial vehicle has attempted to capture an operational government satellite that was never designed to be serviced. "

Explanation: What's happening to galaxy NGC 474? The multiple layers of emission appear strangely complex given the relatively featureless appearance of the elliptical galaxy in less deep images. The cause of the shells is a topic of research, but they are possibly tidal tails related to debris left over from absorbing numerous small galaxies in the past billion years. Alternatively, the shells may be like ripples in a pond, where the ongoing collision with the spiral galaxy just to the right of NGC 474 is causing density waves to ripple through the galactic giant. Regardless of the actual cause, the...

Explanation: Unlike most entries in Charles Messier's famous catalog of deep sky objects, M24 is not a bright galaxy, star cluster, or nebula. It's a gap in nearby, obscuring interstellar dust clouds that allows a view of the distant stars in the Sagittarius spiral arm of our Milky Way galaxy. Direct your gaze through this gap with binoculars or a small telescope and you are looking through a window over 300 light-years wide at stars some 10,000 light-years or more from Earth. Sometimes called the Small Sagittarius Star Cloud, M24's luminous stars stretch across this gorgeous interstellar scene. Spanning over...