Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Six Moons of Saturn
Explanation:How many moons does Saturn have? While the total will likely continue to grow, as of June 2026 the ringed gas giant had 293 confirmed moons. That’s easily more than any other planet of the Solar System, including ruling gas giant Jupiter with a mere 115 confirmed moons. Most of Saturn’s known moons are small, irregular satellites. Many are only few kilometers to a fraction of a kilometer across and grouped in tilted outer orbits. Six of its largest satellites can be seen here, though, in this sharp telescopic Saturnian family portrait taken on August 5. Larger than Earth’s Moon and even slightly larger than inner planet Mercury, Titan, with a diameter of 5,150 kilometers, is at lower right. You can also spot icy major moons Mimas, Tethys, Enceladus, Dione, and Rhea in the frame. Saturn’s first known natural satellite, Titan was discovered in 1655 by Dutch astronomer Christiaan Huygens. During the space age Voyager and Cassini discoveries have added to the swelling ranks of Saturnian moons.
Water covers intertidal mudflats around Roebuck Bay in Western Australia, as seen in this image captured by the OLI (Operational Land Imager) on Landsat 8 on March 18, 2026.
NASA Earth Observatory / Lauren Dauphin
Editor’s Note: Today’s story is the answer to the August Puzzler.
Tides are among the clearest signs of the Moon’s pull on Earth. Just 239,000 miles (385,000 kilometers) away, the Moon’s gravity pulls on Earth’s oceans and solid crust, subtly distorting them into a more oblong shape with bulges roughly extending toward and away from the Moon.
High tides happen throughout Earth’s oceans, but in some places they leave an unusually strong fingerprint on the landscape. Among those places is Roebuck Bay, a crescent-shaped feature in the Kimberley region of Western Australia.
Roebuck Bay’s tidal range can reach a remarkable 9 meters (30 feet). Rising and falling tides repeatedly inundate and expose expansive mudflats, flood broad mangrove forests and salt marshes, and feed branching networks of tidal drainage channels. Many parts of Australia have tidal ranges of 2 meters or less. But the large range at Roebuck Bay is mostly a consequence of northwestern Australia’s unusually wide, shallow continental shelf, which helps amplify tides as they approach the coast.
The image at the top of the page shows the bay on March 18, 2026, when water levels were high. Green mangrove forests grow thickly along the shoreline and line the mouths of a network of evenly spaced, linear tidal creeks. These mangrove forests are dynamic. Analysis of decades of Landsat observations shows them expanding westward by nearly 2 meters per year as sediment from the waterways to the east accumulates in the sheltered bay.
Farther inland, branching networks of tidal drainage channels connect with the tidal creeks, giving the bay its feathered appearance. These channels, partially obscured by thick vegetation in March, were more visible earlier and later in the year, when vegetation was thinner.
Around Roebuck Bay, inland vegetation greens after monsoon rains, peaking in March, and turns brown and dry by June. The Landsat 8 and 9 satellites captured these images throughout 2026.
NASA Earth Observatory / Lauren Dauphin
Monsoonal rains, typically falling between December and March, transform the landscape around the bay into lush grasslands and seasonal wetlands. As the rains fade in May and June and the dry season takes hold, these ephemeral grasses and sedge ecosystems die back, turning the landscape shades of gold and brown. The consistent spacing of the tidal creeks is likely not a tidal effect; it appears to be influenced by the regular spacing of linear dunes in the broader region, as seen in the plains to the east.
The bay’s dramatic tidal and seasonal changes are striking from above, and they also support a bounty of life on the ground. The mangroves serve as nurseries for crustaceans and fish, and the mudflats teem with dozens of types of invertebrates, including snails, worms, crabs, clams, and cockles. Shells and snails can reach an abundance of 2,500 per square meter, according to the Australian government.
This bounty of marine life is a major draw for birds. The bay, one of the most important sites for migratory birds in Australia and a key stop on the East Asian-Australasian Flyway, regularly hosts hundreds of thousands of birds, including plovers, godwits, and knots.
NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. Geological Survey.Story by Adam Voiland.
Downloads
January 29, 2026
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March 18, 2026
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June 20, 2026
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References & Resources
Birdlife International (2026) Roebuck Bay. Accessed August 10, 2026.
Brockmann Consult (2025) Roebuck Bay. Accessed August 10, 2026.
Community College Instructors Bring Astronomy Textbook Into 21st Century
2 min read
Community College Instructors Bring Astronomy Textbook Into 21st Century
Students studying the celestial sphere at Jackson College, Michigan.
Credit: Steven Tuckey
Teaching the beautiful and inspirational science of astronomy using only the conceptual framework offered by a traditional textbook – without incorporating the wealth of incredible resources, images and activities from NASA – falls short of the more modern, active learning experience that could better serve students evolving learning strategies. Three project teams from the NASA Science Activation (SciAct) program – NASA Community College Network (NCCN, led by the SETI Institute) and five of their expert community college instructors; Infiniscope (led by Arizona State University, ASU); and NASA Treks – set out to address this challenge.
In June 2026, these teams gathered for a virtual workshop to lay the groundwork for incorporating active learning components drawn from NASA’s extensive education and visualization resource pool and the widely used but traditionally structured OpenStax Astronomy 101 textbook into Relevant Engaging Active Learning (REAL) courseware for introductory Astronomy, while preserving the core content and clear explanatory narrative of the text.
Over the following two weeks, the instructors each adopted one of the opening five chapters of OpenStax, enhancing the content with active learning modules with an emphasis on materials developed by SciAct project teams, such as NASA Treks, Universe of Learning, and Cosmic Data Stories, to name a few. The results of their efforts were presented in a wrap-up presentation in July and will be field-tested in community college classrooms in Fall 2026.
This workshop served as a proof of concept for exploring whether an existing textbook can be effectively adapted into an active learning tool that will enhance students’ understanding of fundamental astronomical concepts. Next steps will include expanding the program and diving back into OpenStax to systematically reimagine the material into an active learning tool that covers the entire book – and therefore, the entire Universe! Importantly, this effort highlights new and highly impactful possibilities for the dissemination of NASA SciAct resources.
Special thanks to the five community college instructors and their invaluable wisdom, experience, and skills: Carver Bierson (Scottsdale Community College, Scottsdale Arizona), Dan Chase (Modesto Community College, Modesto, California), Dennis Just (Pima Community College, Pima, Arizona), Steve Tuckey (Jackson College, Jackson, Michigan) and Sally Watt (Glendale Community College, Glendale, Arizona).
NCCN, Infiniscope, NASA Treks, and many of the projects that contributed learning materials are supported by NASA cooperative agreement awards and are part of the NASA Science Activation Program portfolio, which connects learners with authentic NASA science experiences through partnerships with educators and community organizations.
NASA+ Debuts on discovery+, Coming Soon to HBO Max
Credit: NASA
As NASA+ continues its expansion across multiple streaming platforms to bring space closer to home, NASA announced Monday programming is next heading to discovery+ and HBO Max. A continuous live feed of NASA+ programming is streaming on discovery+ live channels, while HBO Max will stream NASA’s special events, including the Artemis III mission in 2027.
Viewers on those platforms can stream NASA+ content in Dolby Vision on supported devices, which will bring space exploration to life with vivid colors, sharper contrast, brighter imagery, and richer detail. This enhanced streaming experience will help viewers experience space coverage in a uniquely immersive way.
Future programming may include science mission launches, a test flight for rendezvous and docking with human landing systems, robotic lunar deliveries, the first crewed mission to the Moon under Artemis, and more. As always, NASA+ also remains available for free, with no ads, through the NASA app and on the agency’s website.
“The National Aeronautics and Space Act of 1958 calls on us to share our story of space exploration with the broadest possible audience and we continue to honor that commitment,” said Rebecca Sirmons, general manager of NASA+ at the agency’s Headquarters in Washington. “Artemis II captured the hearts and minds of viewers globally, inspiring the Artemis generation. As we return to the Moon to stay, our goal is to provide transparent, engaging content coverage every step of the way.”
Earlier this year during its Ignition event, NASA shared plans for a bold path forward for the agency, including increasing its cadence of Artemis missions to the lunar surface, and building the first Moon Base, among other agency priorities. These continuous streaming agreements strengthen NASA’s promise to public engagement, making the agency’s mission and educational content available on multiple devices for viewers on their preferred channels
NASA’s James Webb Space Telescope imaged the planetary nebula NGC 2392, the Lion Nebula, using the observatory’s NIRCam and MIRI instruments. The central star’s remains are responsible for the nebula’s structure, including a lion face-shaped bubble of ionized gas and dust “mane.”
Observing across the starry “plains” of space, NASA’s James Webb Space Telescope has taken new images of NGC 2392, nicknamed the Lion Nebula. NASA’s Hubble Space Telescope previously viewed this planetary nebula in 2000, imaging the lion face-shaped target in visible light and revealing features such as the “mane” of hazy, comet-shaped objects. Now Webb has captured a clearer, more detailed view of the Lion Nebula due to its high-resolution imaging.
Lion Nebula (NIRCam and MIRI Image)
NASA’s James Webb Space Telescope imaged the planetary nebula NGC 2392, the Lion Nebula, using the observatory’s NIRCam and MIRI instruments. The central star’s remains are responsible for the nebula’s structure, including a lion face-shaped bubble of ionized gas and dust “mane.”
Image: NASA, ESA, CSA, STScI; Image Processing: Alyssa Pagan (STScI)
At first glance the nebula’s overall structure in Webb’s infrared images, with both the NIRCam (Near Infrared Camera) and MIRI (Mid Infrared Instrument) instruments, may look quite similar to Hubble’s earlier visible-light view. However, Webb’s infrared vision highlights features like compact clumps of dust and a haze of ionized gas. It’s taken several thousand years for this collection of gas and dust to reach its current shape, and the nebula’s components continue to be altered.
The source of these constant changes and the reason for the Lion Nebula’s distinct appearance is located at the center: the remains of a dying star. Though it looks like the button nose of the lion, its energy and radiation are powering the intricate structures seen here.
Lion Nebula (MIRI Image)
NASA’s James Webb Space Telescope’s mid-infrared image of planetary nebula NGC 2392, nicknamed the Lion Nebula, highlights the varying dust structures. Some dust is being destroyed by the dying central star’s radiation, while some dust filaments manage to survive.
Image: NASA, ESA, CSA, STScI; Image Processing: Alyssa Pagan (STScI)
Massive stars undergo supernova explosions at the end of their lives, but these kinds of events are few and far in between. Most of the universe’s stars have lower masses, like the one belonging to NGC 2392. When a lower-mass star can no longer sustain itself with nuclear reactions in its core, the star becomes unstable and pulsates, losing its mass by shedding its outer layers, which then turn into shells of gas and dust called a planetary nebula. (Stars at this life stage are responsible for producing much of the universe’s observable dust.) The star’s radiation drives the ejected material away, leaving behind the very hot stellar core, also known as a white dwarf.
In the Lion Nebula’s case, the death of the oxygen-rich central star has left behind a white dwarf that is “cooking” everything from the inside and producing a bubble of ionized gas as it does. The gas bubble, which forms the lion’s face, is expanding over time and destroying dust that is in its path. Understanding why the swept-up gas has a complex structure of rings and shells, a common feature in planetary nebulae, is an ongoing endeavor.
The mane of the lion is the interior of a dust shell that is being illuminated by the white dwarf at the center. The tufts of hair, which look like cometary tails of material, are compact clumps of dust that have survived the stellar core’s radiation and protect the material that lies behind them.
Webb’s imagery “freezes” this planetary nebula in time, though the star’s death, and its tumultuous effects, go on. NGC 2392 will continue to undergo changes as its gas and dust migrate away from the stellar core. Astronomers estimate the lion will eventually disperse in approximately 10,000 years — a relatively short period in astronomical terms.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
The following sections contain links to download this article’s images and videos in all available resolutions followed by related information links, media contacts, and if available, research paper and Spanish translation links.
Related Images & Videos
Lion Nebula (NIRCam and MIRI Image)
NASA’s James Webb Space Telescope imaged the planetary nebula NGC 2392, the Lion Nebula, using the observatory’s NIRCam and MIRI instruments. The central star’s remains are responsible for the nebula’s structure, including a lion face-shaped bubble of ionized gas and dust “mane.”
Lion Nebula (MIRI Image)
NASA’s James Webb Space Telescope’s mid-infrared image of planetary nebula NGC 2392, nicknamed the Lion Nebula, highlights the varying dust structures. Some dust is being destroyed by the dying central star’s radiation, while some dust filaments manage to survive.
