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Abstract Venus, lacking an intrinsic global dipole magnetic field, serves as a textbook example of an induced magnetosphere, formed by interplanetary magnetic fields (IMF) enveloping the planet. Yet, various aspects of its magnetospheric dynamics and planetary ion outflows are complex and not well understood. Here we analyze plasma and magnetic field data acquired during the fourth Venus flyby of the Parker Solar Probe (PSP) mission and show evidence for closed topology in the nightside and downstream portion of the Venus magnetosphere (i.e., the magnetotail). The formation of the closed topology involves magnetic reconnection—a process rarely observed at non-magnetized planets. In addition, our study provides an evidence linking the cold Venusian ion flow in the magnetotail directly to magnetic connectivity to the ionosphere, akin to observations at Mars. These findings not only help the understanding of the complex ion flow patterns at Venus but also suggest that magnetic topology is one piece of key information for resolving ion escape mechanisms and thus the atmospheric evolution across various planetary environments and exoplanets.

Background:. Unlike in-house call, the Accreditation Council for Graduate Medical Education (ACGME) does not require a postcall day for “home call” shifts. Despite this, we hypothesize that on-call residents are still in the hospital for the majority of their shift despite having the luxury of home call and, thus, are not protected by ACGME postcall duty hour regulations. Methods:. A prospective single center survey study was conducted by surveying junior and senior residents who completed overnight call shifts from January 2023 to April 2023 at one of the busiest level 1 trauma centers in the United States. Data include number of trips into the hospital, hours spent in the hospital, and hours of sleep. Results:. Response rate was 195 of 200 (97.5%) total call shifts from 7 pm to 7 am the next morning. Junior residents reported an average of 3.25, 3.92, and 0.73 hours of sleep when on hand call, face call, and triple call (hand + face + general), respectively. Senior residents reported an average of 4.18 and 4.75 hours of sleep for hand and face call, respectively. Conclusions:. Hours of sleep when taking home call varies widely based on type of call. Junior residents reported significantly decreased sleep and more time in the hospital when taking hand, face, and triple call compared with general call alone. Senior residents reported that both hand and face call result in significantly decreased hours of sleep compared with general call alone. These results highlight the need to discuss ACGME protection for residents taking home call.

Mars lacks a global intrinsic dipole field but possesses localized crustal fields, making it unique in the solar system. Recent observations revealed that electrons can be injected into the crustal fields, and exhibit drift-dispersed bursts due to the magnetic drift motion, which are characterized by increases or decreases in energy over time in the energy spectrum. However, the source of the drift-dispersed electrons and the mechanism of their injection into the crustal fields remains unclear. Here, by leveraging data from the Mars Atmosphere and Volatile EvolutioN mission, along with test-particle simulations, we reveal that the source of dispersed electrons is the precipitating electrons injected into the crustal fields via open field lines. These electrons display as dispersionless bursts near the source location, and as dispersed bursts as they drift away from the source. Thus, the dispersed electrons represent a later stage in the evolution of dispersionless electrons. This evolutionary process closely mirrors that observed within Earth’s dipole field, affirming that the crustal fields function similarly to a mini-magnetosphere.