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Explanation: 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...

“Our test facilities can’t reach the combination of heat flux, pressure, shear stresses, etc., that an actual reentering spacecraft does. We’re always having to wait for the flight test to get the final certification that our system is good to go.”—Jeremy VanderKam, deputy manager for Orion’s heat shield, speaking in 2022 On Wednesday, NASA will attempt to send four astronauts around the moon on a mission called Artemis II. This will be second flight of NASA’s SLS rocket, and the first time the 20-year-old Orion capsule flies with people on board. The trouble is that the heat shield on Orion...

Explanation: 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...

Explanation: 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...

Join us as the Artemis II crew answers questions from NASA's Kennedy Space Center, where they're in protective quarantine ahead of their upcoming flight around the Moon. NASA's Artemis II Q&A from Quarantine | 53:49 NASA | 12.8M subscribers | 20,828 views | March 29 2026(Streamed live 2 hours ago)

The astronaut who prompted NASA’s first medical evacuation earlier this year said Friday that doctors still don’t know why he suddenly fell sick at the International Space Station. Four-time space flier Mike Fincke said he was eating dinner on Jan. 7 after prepping for a spacewalk the next day when it happened. He couldn’t talk and remembers no pain, but his anxious crewmates jumped into action after seeing him in distress and requested help from flight surgeons on the ground. ... Fincke, 59, a retired Air Force colonel, said the episode lasted roughly 20 minutes and he felt fine afterward....

NASA Might Be Able to Reboost the Hubble Space Telescope After All... | 10:37> Ellie in Space | 222K subscribers | 34,141 views | March 25, 2026 [link to the report from Ars Technica]

Explanation: 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...

Explanation: Scanning the skies for galaxies, Canadian astronomer Paul Hickson and colleagues identified some 100 compact groups of galaxies, now appropriately called Hickson Compact Groups. The four prominent galaxies seen in this intriguing telescopic skyscape are one such group, Hickson 44. The Hickson 44 galaxy group is about 100 million light-years distant, far beyond the foreground Milky Way stars, toward the northern springtime constellation Leo. The two spiral galaxies in the center of the image are edge-on NGC 3190 with distinctive, warped dust lanes, and S-shaped NGC 3187. Along with the bright elliptical, NGC 3193 (left) they are also known...

In 2002, a part-time single mother at a small rocketry consultancy was driving on an LA freeway when she decided she was being an idiot for not taking a job at a startup with zero successful launches and seven employees. Gwynne Shotwell joined SpaceX as employee number seven. Her job: convince governments and corporations to buy rides on rockets that didn't exist yet. The Falcon 1 failed three times. On the fourth attempt, September 2008, it reached orbit. Two months later, Shotwell negotiated a $1.6 billion NASA contract that saved the company from bankruptcy. She was promoted to President the...

NewsNation) — The White House Instagram and X account has sparked questions after two mysterious videos were posted to the page on Wednesday night, with one of them later deleted. The first video, a four-second clip posted shortly after 9 p.m. EST, had the camera pointed towards a person’s feet with shoes on, with a female voice heard asking, “It’s launching soon, right?” Another voice could then be heard answering “yes,” according to Newsweek. Across the video, on-screen text could be seen that read “sound on.”

Explanation: In the words of today's astrophotographer, Rositsa Dimitrova, "What have these silent sentinels watched pass across the sky?" The volcanic mo'ai (meaning statue) of Ahu Tongariki stand guard over Rapa Nui (Isla de Pascua, Easter Island), a Polynesian island (annexed by Chile in 1888) located thousands of kilometers off the coast of South America in the Pacific Ocean. Due to the island's remoteness, the mo'ai, with their backs to the dark ocean, are able to gaze upon a clear and vibrant night sky. Pictured, these larger-than-life statues stare at the bright band of the Milky Way, partly obscured by...

NASA is cancelling plans to deploy a space station in ‌lunar orbit and will instead use its components to construct a $20 billion base on the moon’s surface over the next seven years, its new chief Jared Isaacman ​said on Tuesday. Isaacman, who was sworn in at the agency ​in December, made the announcement at the opening of a ⁠day-long event at NASA’s Washington headquarters at which he outlined a ​raft of changes he is making to the agency’s flagship moon program ​Artemis. “It should not really surprise anyone that we are pausing Gateway in its current form and focusing...

Explanation: Is gravity the same over the surface of the Earth? No -- in some places you will feel slightly heavier than others. The featured Earth map video shows in colors and exaggerated highs and lows where the gravitational field of Earth is relatively strong and weak. A low spot, where you would feel slightly lighter, can be seen just off the coast of India, in blue, while a relative high occurs in the mountains of Chile in South America. The cause of these irregularities does not always follow present surface features. Scientists hypothesize that other important factors lie in...

Explanation: What's happening at the end of that street? Pictured here are not auroras but light pillars, a phenomenon typically much closer. In most places on Earth, a lucky viewer can see a Sun pillar, a column of light appearing to extend up from the Sun caused by flat fluttering ice-crystals reflecting sunlight from the upper atmosphere. Usually, these ice crystals evaporate before reaching the ground. During freezing temperatures, however, flat fluttering ice crystals may form near the ground and are sometimes known as a crystal fog. These small ice crystals may then reflect not the Sun but ground lights....

Explanation: What would it look like to leave planet Earth? Such an event was recorded visually in great detail by the MESSENGER spacecraft as it swung back past the Earth in 2005 on its way in toward the planet Mercury. Earth can be seen rotating in this time-lapse video, as it recedes into the distance. The sunlit half of Earth is so bright that background stars are not visible. The robotic MESSENGER spacecraft orbit around Mercury from 2011 to 2015 has conducted the first complete map of the surface. On occasion, MESSENGER peered back at its home world. MESSENGER is...

Explanation: Spiral NGC 1300 and elliptical NGC 1297 are galaxies that lie on the banks of the southern constellation Eridanus (The River). At 70 million light-years distant or more, both are members of the Eridanus Galaxy Cluster. About 100,000 light-years across, at lower left in this sharp, galaxy group photo NGC 1300 is seen face-on with a prominent central bar and grand, sweeping spiral arms. Like other spiral galaxies, including our own barred spiral Milky Way Galaxy, NGC 1300 is thought to have a supermassive central black hole. A contrast in appearance and slightly more distant, NGC 1297 is the...

Explanation: The defining astronomical moment of the equinox today is at 14:46 UTC (March 20). That's when the Sun crosses the celestial equator moving north in its yearly journey through planet Earth's sky, marking the beginning of spring for our fair planet in the northern hemisphere and fall in the southern hemisphere. Then, day and night are nearly equal around the globe. In fact, both day and nighttime exposures from a spring equinox at the Observatorio del Teide in Tenerife, Canary Islands, Spain, are used in this composited skyscape. Over 1,000 images were taken with a fisheye lens and merged...

Explanation: Even if you live with your head in the clouds, you won’t find a jellyfish like this one very often. The featured image shows a SpaceX Falcon 9 rocket launch from Cape Canaveral in Florida on March 4. The launch happened 52 minutes before sunrise, and the second stage rocket exhaust plume was high enough in the sky to catch the light of the rising sun, while the photographer was still in the dark. This combination of light and shadow, possible at dawn or dusk, makes the exhaust, mostly water vapor and carbon dioxide, appear as a glowing cloud....

Explanation: A lone tree stands in a quiet meadow in Guadalajara, Spain, silhouetted against the Cygnus region rising above like flames in the night sky. This deep night skyscape is a composite of exposures that reveals a range of brightness and color human eyes can't quite see on their own. Spanning over a thousand times the angular size of the full moon, Cygnus sets the sky afire with active star formation where clouds of gas and dust collapse under gravity until nuclear fusion ignites and new stars are born. These stars ionize the surrounding hydrogen gas, causing it to glow...