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Explanation: In 1716, English astronomer Edmond Halley noted, "This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent." Of course, M13 is now less modestly recognized as the Great Globular Cluster in Hercules, one of the brightest globular star clusters in the northern sky. Sharp telescopic views like this one reveal the spectacular cluster's hundreds of thousands of stars. At a distance of 25,000 light-years, the cluster stars crowd into a region 150 light-years in diameter. Approaching the cluster core, upwards of 100 stars could be contained...

Explanation: What lies in the heart of Orion? Trapezium: four bright stars, that can be found near the center of this sharp cosmic portrait. Gathered within a region about 1.5 light-years in radius, these stars dominate the core of the dense Orion Nebula Star Cluster. Ultraviolet ionizing radiation from the Trapezium stars, mostly from the brightest star Theta-1 Orionis C powers the complex star forming region's entire visible glow. About three million years old, the Orion Nebula Cluster was even more compact in its younger years and a dynamical study indicates that runaway stellar collisions at an earlier age may...

This view of tracks trailing NASA’s Curiosity was captured July 26, 2025, as the rover simultaneously relayed data to a Mars orbiter. Combining tasks like this more efficiently uses energy generated by Curiosity’s nuclear power source, seen here lined with rows of white fins at the back of the rover. Credit: NASA/JPL-Caltech Thirteen years into its mission, Curiosity is smarter and more efficient than ever. New multitasking abilities, self-managed naps, and clever engineering fixes are keeping it powered and mobile as it investigates ancient Martian landscapes for signs of past habitability. Thirteen years after touching down on the Martian surface,...

Explanation: Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Perseus. That is why the meteor shower that peaks tonight is known as the Perseids -- the meteors all appear to come from a radiant toward Perseus. In terms of parent body, though, the sand-sized debris that makes up the Perseids meteors come from Comet Swift-Tuttle. The comet follows a well-defined orbit around our Sun, and the part of the orbit that approaches Earth is superposed in front of Perseus. Therefore, when Earth crosses this orbit, the...

Explanation: Everybody sees the Sun. Nobody's been there. Starting in 2018, though, NASA launched the robotic Parker Solar Probe (PSP) to investigate regions near to the Sun for the first time. The featured time-lapse video shows the view looking sideways from behind PSP's Sun shield in December during the closest approach of any human-made spacecraft to the Sun, looping down to only about five solar diameters above the Sun's hot surface. The PSP's Wide Field Imager for Solar Probe (WISPR) cameras took these images over seven hours, but they are digitally compressed here into about 5 seconds. The solar corona,...

Explanation: What's that strange light down the road? Dust orbiting the Sun. At certain times of the year, a band of sun-reflecting dust from the inner Solar System appears prominently just after sunset -- or just before sunrise -- and is called zodiacal light. Although the origin of this dust is still being researched, a leading hypothesis holds that zodiacal dust originates mostly from faint Jupiter-family comets and slowly spirals into the Sun. Recent analysis of dust emitted by Comet 67P, visited by ESA's robotic Rosetta spacecraft, bolsters this hypothesis. Pictured when climbing a road up to Teide National Park...

A SpaceX Dragon spacecraft carrying NASA astronauts Anne McClain and Nichole Ayers along with mission specialists JAXA (Japan Aerospace Exploration Agency) astronaut Takuya Onishi, and Roscosmos cosmonaut Kirill Peskov splashed down in the Pacific Ocean on Aug. 9, 2025. Credit: SpaceX Splashdown! SpaceX Crew-10 astronauts and cosmonaut back on Earth | 12:06 VideoFromSpace | 2.02M subscribers | 47,832 views | August 9, 2025

Explanation: Discovered on July 1 with the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, 3I/ATLAS is so designated as the third known interstellar object to pass through our Solar System. It follows 1I/ʻOumuamua in 2017 and the comet 2I/Borisov in 2019. Also known as C/2025 N1, 3I/ATLAS is a comet. A teardrop-shaped cloud of dust, ejected from its icy nucleus warmed by increasing sunlight, is seen in this sharp image from the Hubble Space Telescope captured on July 21. Background stars are streaked in the exposure as Hubble tracked the fastest comet ever recorded...

Lovell was part of a total of four space missions: Gemini VII, Gemini XII, Apollo 8 and Apollo 13. NASA Astronaut Jim Lovell, who famously led the historic Apollo 13 moon mission, died on Thursday at the age of 97, his family announced Friday.Lovell was part of a total of four space missions: Gemini VII, Gemini XII, Apollo 8 and Apollo 13. Lovell was most known for his calm leadership during Apollo 13's tragic flight, which experienced a major oxygen tank explosion far away from Earth.The astronaut's family highlighted Lovell's "legendary leadership in pioneering human space flight," and observed that...

In 1968, the Apollo 8 crew of Lovell, Frank Borman and William Anders was the first to leave Earth's orbit and the first to fly to and circle the moon. They could not land, but they put the U.S. ahead of the Soviets in the space race. During the harrowing Apollo 13 flight in April 1970, Lovell was supposed to be the fifth man to walk on the moon. But Apollo 13's service module, carrying Lovell and two others, experienced a sudden oxygen tank explosion on its way to the moon. The astronauts barely survived, spending four cold and clammy...

Explanation: One of the all-time historic skyscapes occured in July 1054, when the Crab Supernova blazed into the dawn sky. Chinese court astrologers first saw the Guest Star on the morning of 4 July 1054 next to the star Tianguan (now cataloged as Zeta Tauri). The supernova peaked in late July 1054 a bit brighter than Venus, and was visible in the daytime for 23 days. The Guest Star was so bright that every culture around the world inevitably discovered the supernova independently, although only nine reports survive, including those from China, Japan, and Constantinople. This iPhone picture is from...

Explanation: This stunning starfield spans about three full moons (1.5 degrees) across the heroic northern constellation of Perseus. It holds the famous pair of open star clusters, h and Chi Persei. Also cataloged as NGC 869 (right) and NGC 884, both clusters are about 7,000 light-years away and contain stars much younger and hotter than the Sun. Separated by only a few hundred light-years, the clusters are both 13 million years young based on the ages of their individual stars, evidence that both clusters were likely a product of the same star-forming region. Always a rewarding sight in binoculars or...

Explanation: What's that green streak in front of the Andromeda galaxy? A meteor. While photographing the Andromeda galaxy in 2016, near the peak of the Perseid Meteor Shower, a small pebble from deep space crossed right in front of our Milky Way Galaxy's far-distant companion. The small meteor took only a fraction of a second to pass through this 10-degree field. The meteor flared several times while braking violently upon entering Earth's atmosphere. The green color was created, at least in part, by the meteor's gas glowing as it vaporized. Although the exposure was timed to catch a Perseid meteor,...

Explanation: Why is this nebula so complex? The Webb Space Telescope has imaged a nebula in great detail that is thought to have emerged from a Sun-like star. NGC 6072 has been resolved into one of the more unusual and complex examples of planetary nebula. The featured image is in infrared light with the red color highlighting cool hydrogen gas. Study of previous images of NGC 6072 indicated several likely outflows and two disks inside the jumbled gas, while the new Webb image resolves new features likely including one disk's edge protruding on the central left. A leading origin hypothesis...

Two of NASA's historic data-collecting missions — used by scientists and earthbound agriculturalists to track carbon dioxide and crop health — may be permanently grounded as the Trump administration looks to shrink the agency's spending. When they launched over a decade ago, the satellites known as the Orbiting Carbon Observatories (OCOs) revolutionized the collection of carbon data and greenhouse gas science. To put it simply, the OCOs changed how we understand our impact on the planet. Experts rely on the data for studies on greenhouse gases and severe weather and climate disasters, as well as other practical uses, including modeling...

President Donald Trump has people doing a double-take with the latest news about plans to not only get us back to the Moon, but build a nuclear reactor on the lunar surface and soon. According to documents obtained by Politico, interim NASA administrator and Transportation Secretary Sean Duffy will announce expedited plans with a definitive timeline to get a reactor built and take significant steps to improve U.S. efforts in the second space race. The report noted that NASA previously revealed plans, but no timeline was put in place. "It is about winning the second space race," a NASA senior...

The Trump administration aims to accelerate the construction of a nuclear reactor on the moon, Transportation Secretary and acting NASA Administrator Sean Duffy wrote in a memo distributed internally on Monday. The space agency has previously explored the possibility of installing an electricity-generating nuclear reactor on the lunar surface capable of powering a sustained human presence, but Duffy intends to fast-track the project and more than double the reactor’s power output, according to documents obtained by The Post. “To properly advance this critical technology to be able to support a future lunar economy, high power energy generation on Mars, and...

Explanation: What are these gigantic blue arcs near the Andromeda Galaxy (M31)? Discovered in 2022 by amateur astronomers, the faint arcs -- dubbed SDSO 1 -- span nearly the same angular size as M31 itself. At first, their origin was a mystery: are they actually near the Andromeda Galaxy, or alternatively near to our Sun? Now, over 550 hours of combined exposure and a collaboration between amateur and professional astronomers has revealed strong evidence for their true nature: SDSO 1 is not intergalactic, but a new class of planetary nebula within our galaxy. Dubbed a Ghost Planetary Nebula (GPN), SDSO...

Explanation: In about a week the Perseid Meteor Shower will reach its maximum. Grains of icy rock will streak across the sky as they evaporate during entry into Earth's atmosphere. These grains were shed from Comet Swift-Tuttle. The Perseids result from the annual crossing of the Earth through Comet Swift-Tuttle's orbit, and are typically the most active meteor shower of the year. Although it is hard to predict the level of activity in any meteor shower, in a clear dark sky an observer might see a meteor a minute. This year's Perseids peak just a few days after full moon,...

The fresh crew includes NASA astronauts Zena Cardman and Mike Fincke, Kimiya Yui of the Japan Aerospace Exploration Agency (JAXA), and Oleg Platonov of Roscosmos. SpaceX delivered a new crew to the International Space Station on Saturday in a 15-hour trip from NASA's Kennedy Space Center. The astronauts will be in space for at least six months. The current crew is expected to return to Earth by Wednesday, .