A new framework assigns probabilities to inferred active regions on the Sun’s far side before adding them to magnetic-field maps. Its chosen filter rejected about 90% of ghost detections, with 93% precision, while retaining approximately 52% of real detections. The improved maps capture otherwise missing magnetic flux, but the study does not directly establish better forecasts of individual solar storms. An active region can grow on the Sun while remaining completely hidden from Earth. By the time rotation brings it into view, a magnetic-field model relying on Earth-facing observations may already be missing part of its history. A Southwest Research Institute-led team has developed a way to reduce that blind spot without accepting every indirect detection as real. Its framework assigns probabilities to suspected far-side active regions, then incorporates selected detections into a model of the Sun’s surface magnetism. The study, published in The Astrophysical Journal Supplement Series, was led by Bibhuti Kumar Jha, a research scientist in SwRI’s Boulder, Colorado, division. Co-author Lisa Upton is a lead scientist at the same office. The work …

Webb tracked atmospheric changes on WISE 0855, a cold, free-floating world about 7.5 light-years away. The spectra distinguish variable carbon monoxide and phosphine signatures from changes consistent with patchy water clouds. Atmospheric models support the cloud interpretation, while the object’s rotation period and some chemical details remain uncertain. A nearby world has weather that astronomers can now follow in unusual detail. Over eleven hours, the James Webb Space Telescope watched its infrared light change, revealing separate clues about shifting clouds and gases rising from deeper layers. The object, WISE 0855, floats through space without a host star. Roughly Jupiter-sized and about 7.5 light-years away, it is the coldest known brown dwarf. Its atmosphere offers a rare opportunity to investigate planet-like weather beyond the solar system. Brittany Miles of the University of Arizona‘s Steward Observatory led the international team. The study, accepted by The Astronomical Journal and available on arXiv, presents evidence that patchy water clouds change thickness while a separate chemical signal varies underneath. That interpretation comes from comparing spectra with atmospheric models. Webb did …

A white dwarf’s unusual chemistry points to a giant planet containing material shed during the star’s death. If confirmed, the system would provide the first evidence of a second-generation planet around a white dwarf. A 4.4-day brightness cycle supports the interpretation, but the planet’s existence and formation history remain unconfirmed. A dead star’s atmosphere contains an unusual clue to a possible new beginning: heavy elements that may come from a planet formed after the star died. The white dwarf HS 0209+0832 appears to be collecting material unlike the rocky debris normally detected around these stellar remnants. A University of Warwick-led team reports the finding in a study published in Nature Astronomy. Supported by the European Research Council, the researchers identify the system as a second-generation planet candidate. Their evidence combines chemical measurements, stellar atmosphere models and a repeating brightness signal. Such a world would differ from planets that survive their host star’s transformation. Rather than forming alongside a young star, it would contain material expelled during stellar death. The proposed explanation remains an inference, although …

A new analysis of FAST observations from 33 planetary systems identified an unexplained narrowband signal toward K2-155. Polarization differences and similar signals toward other stars make terrestrial or instrumental interference the more plausible explanation. The study tests a machine-learning method for reducing large radio datasets to signals that astronomers can inspect closely. A thin radio signal survived several screening steps in observations pointed toward K2-155, a star roughly 238 light-years away. It occupied a narrow frequency band, drifted slowly, and appeared only in the telescope beam tracking that system. Those features earned it closer examination, but they did not establish an extraterrestrial origin. Further checks produced warning signs. The signal appeared strongly in only one polarization channel, while similar features surfaced during observations of three other stars. The researchers consider human-made or instrumental interference more plausible than a transmission from another civilization. The finding appears in The Astronomical Journal, in a study led by Zi-Qi Li of Beijing Normal University. Its main contribution is a new method for sorting radio observations, tested on existing data …

A new global model suggests ancient Mars did not receive prebiotic formaldehyde evenly. Rainfall and atmospheric water vapor concentrated its delivery in particular regions. Tharsis and Elysium emerged as major hotspots, with modeled formaldehyde deposition approaching 50 milligrams per square meter per year, roughly ten times the global average. The calculations estimate how much formaldehyde reached the surface, not how much survives today, but the resulting map could help future missions test whether atmospheric chemistry contributed to Martian organic matter. Mars may once have possessed something its barren surface no longer reveals: a geographically uneven rain of organic building material. A new global simulation suggests that formaldehyde produced in the ancient Martian atmosphere fell preferentially onto wetter parts of the planet. Mountainous regions such as Tharsis and Elysium received some of the largest modeled deposits, potentially creating localized environments favorable for increasingly complex organic chemistry. This time, the researchers asked where that material would actually have gone. Water controlled both production and delivery Formaldehyde, or H2CO, is chemically simple but important to origin-of-life research. Once …

A short gamma-ray burst lasting only about 0.4 seconds was followed by nearly 10 minutes of soft X-rays, providing unusually direct evidence that some neutron star mergers can remain active long after their gamma-ray flash ends. Follow-up observations measured a redshift of 0.661 and found no accompanying supernova, while the X-ray variability and spectral evolution pointed toward continued activity from the merger’s central engine. The researchers favor a rapidly spinning, strongly magnetized neutron star, or magnetar, as the remnant, raising the possibility that some unexplained fast X-ray transients are hidden signatures of compact-object mergers. A cosmic explosion detected on July 4, 2025, looked ordinary for less than a second. Then it did something that challenged the usual picture of how neutron star mergers fade. The event, GRB 250704B, produced a gamma-ray burst lasting only about 0.37 seconds, comfortably within the class of short bursts associated with compact-object mergers. At lower energies, however, the Einstein Probe satellite recorded soft X-rays for nearly 10 minutes. An international team including researchers at the University of Rome Tor Vergata …

Earth and Mars may have formed through surprisingly different mixtures of pebble accretion, planetesimal collisions and giant impacts, despite growing beside each other in the same young Solar System. Chemical modeling suggests at least 75% of Earth’s mass came from two protoplanets that grew mainly by capturing pebbles, while roughly 73% of Mars came from volatile-depleted planetesimals. The study uses the loss of moderately volatile elements as a record of planetary growth, providing a possible new way to reconstruct the formation and habitability of rocky worlds around other stars. Earth and Mars emerged from the same swirling disk of gas and dust, separated today by less than 80 million kilometers at their closest approach. Their common birthplace might suggest that the two rocky planets were assembled through broadly similar processes. Their chemistry tells a different story. A University of Copenhagen-led study finds that Earth appears to have been built primarily from large protoplanets that themselves grew by sweeping up millimeter- to centimeter-sized pebbles. Mars, by contrast, acquired most of its mass from collisions with much …

A new search of the nearby binary system 70 Ophiuchi AB found no convincing evidence for giant planets, despite combining modern precision measurements with more than a century of observations. The analysis rules out Jupiter-mass planets across much of the system’s inner regions, but smaller worlds remain possible, including planets in locations where liquid water could potentially exist. By establishing unusually precise stellar orbits and separating apparent planet signals from stellar activity, the work gives future observatories a cleaner target for searching for rocky worlds only 16 light-years away. One of astronomy’s oldest suspected planetary systems has just undergone its most sensitive search yet, and the biggest planets scientists might have expected to find are not there. Astronomers led by the University of Michigan studied 70 Ophiuchi AB, a pair of nearby K-type stars about 16 light-years from Earth. By combining more than a century of observations with new high-precision measurements, they found no statistically convincing evidence for giant planets around either star. The absence is scientifically useful. Researchers can now rule out Jupiter-mass planets …

NASA’s Juno spacecraft captured the most detailed plasma-wave measurements yet at Jupiter’s bow shock, revealing stronger nonlinear behavior than typically seen at Earth. Researchers detected ion-acoustic waves with multiple harmonics and intense electron cyclotron drift instability, giving Jupiter more ways to transfer solar-wind energy into particle heating. Juno also recorded magnetic structures repeating about every 8.3 seconds, evidence that Jupiter’s shock may repeatedly break down and reform under the intense incoming solar wind. An invisible shock wave surrounding Jupiter is giving physicists a rare look at how nature handles enormous flows of energy without ordinary particle collisions. NASA’s Juno spacecraft recorded unusually detailed electrical and magnetic activity while crossing Jupiter’s bow shock in December 2024. The observations revealed a surprisingly rich collection of plasma waves, including multiple harmonics that could help heat a wider range of particles than comparable processes near Earth. The findings come from a University of Iowa-led international team and were published in Nature Communications under the title “Plasma wave observations from Juno spacecraft at the Jovian bow shock.” Researchers also found …

New solar-evolution models suggest the young Sun may have swallowed a rocky super-Earth, leaving a chemical fingerprint beneath its convection zone that could still affect the Sun’s internal structure today. The best-fitting models favor an engulfed planet in the super-Earth range, with several solutions pointing to roughly 5 to 10 Earth masses while simultaneously improving agreement with helioseismic measurements and the Sun’s unusually low lithium abundance. The scenario remains a hypothesis rather than evidence that a lost planet definitely existed, but calculations indicate a compact rocky world could penetrate deeply into the young Sun without being destroyed by ordinary aerodynamic ablation alone. The solar system may once have contained a world several times larger than Earth that no longer exists. Rather than being ejected into interstellar space or colliding with another planet, it may have disappeared inside the Sun. A new modeling study suggests such an event could have left a chemical fingerprint deep enough inside our star to survive for billions of years. Researchers found that adding the engulfment of a super-Earth to models …