As scientists continue to explore the vast expanse of our solar system, they are constantly reminded that there is still much we don’t know about its origins and evolution. A recent discovery in the asteroid Ryugu has shed new light on this phenomenon, leaving researchers with more questions than answers.

The Hayabusa2 mission returned pristine samples from the C-type asteroid Ryugu on December 6, 2020. These samples were crucial for improving our understanding of primitive asteroids and their role in forming the Solar System. However, a research team at Hiroshima University made an unexpected find – the presence of djerfisherite, a potassium-containing iron-nickel sulfide mineral, in one of these Ryugu grains.

Djerfisherite is typically associated with enstatite chondrites, which form under very reduced conditions. Its occurrence in CI chondrites, like those found in Ryugu, has sparked debate among scientists about the asteroid’s history and formation processes. Associate Professor Masaaki Miyahara explained that djerfisherite’s presence suggests either an unexpected local environment or long-distance transport in the early solar system.

The research team had been conducting experiments to understand the effects of terrestrial weathering on Ryugu grains. While observing these grains using field-emission transmission electron microscopy (FE-TEM), they stumbled upon djerfisherite in grain number 15, sample plate C0105-042. This finding opens new avenues for understanding the complexity of primitive asteroids and challenges our previous notion that Ryugu is compositionally uniform.

Ryugu’s parent body is believed to have formed between 1.8 to 2.9 million years after the beginning of the Solar System. During this time, it existed in the outer region of the solar system, where water and carbon dioxide were present as ice. The temperature inside the parent body remained below approximately 50℃. However, the presence of djerfisherite in Ryugu suggests that materials from different formation histories may have mixed early in the solar system’s evolution.

Two hypotheses have been proposed to explain this phenomenon: either djerfisherite arrived from another source during the formation of Ryugu’s parent body or it was formed intrinsically when the temperature of Ryugu was raised to above 350 ℃. Preliminary evidence indicates that the intrinsic formation hypothesis is more likely to be true.

Ultimately, scientists aim to reconstruct the early mixing processes and thermal histories that shaped small bodies like Ryugu. By understanding these events, we can gain a better grasp of planetary formation and material transport in the early solar system. The discovery of djerfisherite in asteroid Ryugu has taken us one step closer to unraveling this enigma.

The recent study by a team of solar physicists has provided unprecedented insight into the fine-scale structure of the Sun’s surface. Using the powerful U.S. National Science Foundation (NSF) Daniel K. Inouye Solar Telescope on Maui, scientists have observed ultra-narrow bright and dark stripes on the solar photosphere for the first time in such high detail. These stripes, called striations, are the result of curtain-like sheets of magnetic fields that ripple and shift like fabric blowing in the wind.

As light from the hot granule walls passes through these magnetic “curtains,” the interaction produces a pattern of alternating brightness and darkness that traces variations in the underlying magnetic field. If the field is weaker in the curtain than in its surroundings, it appears dark; if it’s relatively stronger, it appears bright.

The researchers used the Inouye Solar Telescope’s Visible Broadband Imager (VBI) instrument operating in the G-band, a specific range of visible light that highlights areas with strong magnetic activity. This setup allowed them to observe the solar photosphere at an impressive spatial resolution better than 0.03 arcseconds, which is the sharpest ever achieved in solar astronomy.

The study confirms that these striations are signatures of subtle but powerful magnetic fluctuations – variations of only a hundred gauss – that alter the density and opacity of the plasma, shifting the visible surface by mere kilometers. These shifts, known as Wilson depressions, are detectable thanks to the unique resolving power of the 4-meter primary mirror of the NSF Inouye Solar Telescope.

Studying the magnetic architecture of the solar surface is essential for understanding the most energetic events in the Sun’s outer atmosphere – such as flares, eruptions, and coronal mass ejections – and improving space weather predictions. This discovery not only enhances our understanding of this architecture but also opens the door to studying magnetic structures in other astrophysical contexts – and at small scales once thought unachievable from Earth.

The findings were published in The Astrophysical Journal Letters under the title “The striated solar photosphere observed at 0.03” resolution.”

The Apollo astronauts stumbled upon an unexpected treasure on the lunar surface – tiny, bright orange glass beads that had been frozen in time for billions of years. These minuscule, 1mm-wide capsules hold secrets about the moon’s explosive past, revealing a chapter of volcanic eruptions that shaped the satellite’s history.

Researchers led by Thomas Williams, Stephen Parman, and Alberto Saal from Brown University, in collaboration with WashU scientists, have employed cutting-edge techniques to study these ancient artifacts. Using instruments like NanoSIMS 50, atom probe tomography, scanning electron microscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy, they have gained unprecedented insights into the surface of the beads.

Each glass bead is a testament to the moon’s volcanic activity, where lava droplets solidified instantly in the cold vacuum surrounding the satellite. The colors, shapes, and chemical compositions of these tiny minerals are unlike anything found on Earth, serving as probes into the pressure, temperature, and chemical environment of lunar eruptions 3.5 billion years ago.

The study reveals that the style of volcanic eruptions changed over time, much like reading the journal of an ancient lunar volcanologist. These findings not only shed light on the moon’s past but also demonstrate the importance of preserving samples for future generations, as technology advances and new instruments become available to uncover hidden secrets.