On June 17th, much of North America can watch the Moon occult Venus in the daytime sky. All you need are binoculars.
The post See Venus Disappear in Broad Daylight on June 17th appeared first on Sky & Telescope.
The hunt for Planet Nine continues as new discoveries make the Solar System’s biggest mystery even harder to solve. Is there a massive undiscovered planet on the outer reaches of the Solar System? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers had put [...]
A rare meteorite recovered from the Sahara Desert could be a fragment of a Moon-size body that met a violent end in the earliest days of the solar system.
The post Did A Moon-Size Planet Grow Fast and Die Young in the Early Solar System? appeared first on Sky & Telescope.
NASA pushed its Deep Space Network beyond its limits during the Artemis I mission nearly four years ago. The global array of deep space communications antennas couldn't keep up with the routine demands of 40 robotic science missions and the extraordinary surge required by NASA's Orion space capsule as it flew around the Moon.
The experience in late 2022 reduced or delayed downlinks from several high-profile science missions, including the James Webb Space Telescope and Mars rovers, as the data-hungry Artemis I mission took priority on NASA's communications network. And that was before the first Artemis mission with astronauts onboard. When Artemis II launched April 1, NASA called upon the Deep Space Network (DSN) again to connect Mission Control to the Orion capsule as it soared more than a quarter of a million miles from Earth.
With a crew of four flying inside the spacecraft, the agency's appetite for data from Orion on Artemis II was even higher than it was on Artemis I. But at a little more than nine days, the Artemis II mission was shorter than the 25 days Artemis I spent in space, helping alleviate the communications overload. Artemis I also launched 10 small CubeSats into deep space, many of which required tracking and telecom services from the DSN. Artemis II carried fewer CubeSats.
© NASA/JPL-Caltech
NASA pushed its Deep Space Network beyond its limits during the Artemis I mission nearly four years ago. The global array of deep space communications antennas couldn't keep up with the routine demands of 40 robotic science missions and the extraordinary surge required by NASA's Orion space capsule as it flew around the Moon.
The experience in late 2022 reduced or delayed downlinks from several high-profile science missions, including the James Webb Space Telescope and Mars rovers, as the data-hungry Artemis I mission took priority on NASA's communications network. And that was before the first Artemis mission with astronauts onboard. When Artemis II launched April 1, NASA called upon the Deep Space Network (DSN) again to connect Mission Control to the Orion capsule as it soared more than a quarter of a million miles from Earth.
With a crew of four flying inside the spacecraft, the agency's appetite for data from Orion on Artemis II was even higher than it was on Artemis I. But at a little more than nine days, the Artemis II mission was shorter than the 25 days Artemis I spent in space, helping alleviate the communications overload. Artemis I also launched 10 small CubeSats into deep space, many of which required tracking and telecom services from the DSN. Artemis II carried fewer CubeSats.
© NASA/JPL-Caltech
Planetary scientists analyzing a lunar meteorite known as Northwest Africa (NWA) 12593 have uncovered evidence of an asteroid impact that occurred 3.5 billion years ago on the Moon, helping to reconstruct a period of intense bombardment that left lasting marks across the inner Solar System.
The post Lunar Meteorite Preserves Evidence of Colossal Asteroid Strike appeared first on Sci.News: Breaking Science News.
Eugene Parker, pioneer of theoretical solar and plasma astrophysics, was born June 10, 1927. Parker revolutionized the field of heliophysics, notably by first proposing the existence of the solar wind — a stream of charged particles ejected from the Sun — in 1958. His theory was confirmed by Mariner II in 1962. Among many otherContinue reading "June 10, 1927: The birth of Eugene Parker"
The post June 10, 1927: The birth of Eugene Parker appeared first on Astronomy Magazine.
A rare meteorite found in the Sahara Desert has revealed evidence of a giant ancient world that once existed in our solar system but later disappeared. Scientists believe this lost world formed about 4.5 billion years ago, during the early days of the solar system. It may have been as large as the Moon or […]
The post Rare Sahara meteorite uncovers a hidden planet from the early solar system appeared first on Knowridge Science Report.
Using the SETI Institute’s Allen Telescope Array, a 42-element radio interferometer at Hat Creek Radio Observatory in Hat Creek, California, astronomers probed 3I/ATLAS for artificial radio transmissions but found only human-made interference.
The post Astronomers Scan Interstellar Object 3I/ATLAS for Alien Radio Signals appeared first on Sci.News: Breaking Science News.
NASA has ended its attempts to reconnect with the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft and begun decommissioning the orbiter, closing the book on a mission that spent over a decade studying how Mars lost its atmosphere. At a June 3 media conference, NASA officials announced that an anomaly review board — which wasContinue reading "NASA fails to reestablish contact, decommissions MAVEN"
The post NASA fails to reestablish contact, decommissions MAVEN appeared first on Astronomy Magazine.
A new study finds that Uranus' moons almost certainly didn't survive the solar system's violent early chaos intact.
Editor’s Note: Astrobites is a graduate-student-run organization that digests astrophysical literature for undergraduate students. As part of the partnership between the AAS and astrobites, we occasionally repost astrobites content here at AAS Nova. We hope you enjoy this post from astrobites; the original can be viewed at astrobites.org.
Title: Dynamics of Planetary Rings Under Thermal Forces
Authors: Wen-Han Zhou et al.
First Author’s Institution: The University of Tokyo
Status: Published in ApJL
If you ask anyone what their favourite planet is, the answer you’ll most likely hear is Saturn. Why? Why else than the beautiful and intricate ring system surrounding the gas giant. The other gas and ice giants in our solar system — Jupiter, Uranus, and Neptune — have ring systems themselves but none quite as striking as Saturn’s. Would it surprise you to learn that astronomers’ best models have not yet totally explained why Saturn’s rings look the way they do?
In contrast, it may not surprise you to hear that people have been trying to explain the rings for as long as we have seen them with telescopes. We now know that planetary rings are collections of relatively small particles (think micrometre up to metre sized), most likely having once been the material of a larger body that was disrupted either by collisions or tidal forces. This material, due to the gravity of its local planet, is sculpted into a flat disc where more subtle interactions then lead to substructure forming within the disc such as gaps and ringlets. Many of these substructures are explained by well-understood physics — for example gaps being carved by embedded moonlets or resonances sculpting ring edges — though there remain some outstanding problems in our understanding.
The authors of today’s article set their sights on the problematic inner edge of Saturn’s A ring (Figure 1). They describe some mechanisms — namely the collisions of micrometeoroids within the rings — by which a sharp ring edge can be maintained, but there exists a gap in the understanding of how such an edge can form in the first place. All hope is not lost, though, as today’s authors reintroduce a physical process they call the “eclipse–Yarkovsky” effect, which seems to explain these phenomena.
Figure 1: A horizontally sliced image of Saturn’s rings shows the rich substructure and gaps within the various rings. Saturn, which is not shown here, would be to the left of the image. The authors of today’s article are particularly concerned with the bright and sharp inner (left side) edges of the A and B rings. Click to enlarge. [NASA/JPL/Space Science Institute]
The idea behind this process revolves entirely around light. When sunlight hits a particle within a planetary ring, non-absorbed sunlight imparts a little “bump” onto a particle, ever so slightly altering its trajectory. At the same time, some of the sunlight is absorbed into the particle, which heats it up; light is soon re-emitted via thermal radiation, which, again, can slightly change the trajectory of these tiny particles. From a point on the surface of each ring particle (see rightmost side of Figure 2), the photons from this thermal radiation are all emitted in random directions; however, across the whole surface of the particle there is a net force! These tiny particles are spinning, and so the side just near “sunset” is hottest and emitting the most thermal photons. In this way, the pressure from the sunlight plus the thermal radiation of each particle imparts a net torque on the ring itself which changes the angular momentum of the ring.
Figure 2: Starlight is the main source of light onto the particles that make up a planetary ring (right panel) though reflected light from the planet’s surface hits it too. This light “heats up” the ring and forms an asymmetry as the ring is eclipsed by the planet, which produces a net force. [Zhou et al. 2026]
After today’s authors detailed all of the math involved in this process (and there is a lot), they put it into practice to try to help explain Saturn’s curious rings. Including the eclipse–Yarkovsky effect together with other known effects that drive ring evolution allowed them to reproduce the optical depth profile (how thick the ring looks) of Saturn’s A ring better than ever before (notably the sharp inner edge in Figure 3). On top of this, the effect provides another avenue for moonlet formation in the outer edges of ring systems as the positive torque from the effect drives material out toward and away from the Roche limit.
Figure 3: The authors try to explain the current structure of Saturn’s A ring by initialising it with a Gaussian profile of optical thickness versus radius (black dot-dashed line) and evolving it for 81 million years under different effects. When viscous effects are included (blue dashed line), the ring spreads out, but it’s only when the eclipse–Yarkovsky (EY) effect is included (red line) that the model closely matches the observed data (grey line). [Zhou et al. 2026]
Original astrobite edited by Wasi Naqvi.
About the author, Ryan White:
I am a first-year PhD student at Macquarie University in Australia, working mainly on binary/multiple systems with massive stars (Wolf–Rayets in particular!). Outside of study, I’m probably drinking coffee, baking, reading, or going for a run. You can also find me procrastinating on Bluesky @astroryan.bsky.social.
The post Shining a Light on the Shadowy Movements in Saturn’s Rings appeared first on AAS Nova.
Why does one side of the Moon have a lot of craters, while the other side does not? Stephen LogesBrooksville, Florida When the first photos of the Moon’s farside were obtained, people usually expressed the difference between the back and the front in terms of “more craters on the back.” It might be better toContinue reading "Why does one side of the Moon have a lot of craters, while the other does not?"
The post Why does one side of the Moon have a lot of craters, while the other does not? appeared first on Astronomy Magazine.
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