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The Mindat open data service, encompassing data from over 6,000 mineral species and 400,000 localities, has big potential to support the work of mineral exploration by providing insights into mineral associations, paragenetic modes, and visual network analyses through labeled photographs. These tools enable geologists to identify indicator minerals, understand mineral formation sequences, and visually assess mineral assemblages. Mineral association analysis highlights minerals commonly found together, while paragenetic studies offer clues to formation environments. Visual networks of mineral relationships provide rapid identification references. Together, these resources raise new opportunities to enable data-driven strategies that eventually enhance the efficiency and accuracy of mineral exploration. 

The Magnetospheric Multi-scale Mission has frequently observed periodic bursts of counterstreaming electrons with energies ranging from ≈ 30 to 500 keV at the Earth's magnetospheric boundary layers, termed “microinjections.” Recently, a source region for microinjections was discovered at the high-latitude magnetosphere where microinjections showed up simultaneously at all energy channels and were organized by magnetic field variation associated with ultra low frequency mirror mode waves (MMWs) with ≈ 5 min periodicity. These MMWs were associated with strong higher frequency electromagnetic wave activity. Here, we have identified some of these waves as electromagnetic ion cyclotron (EMIC) waves. EMIC waves and parallel electric fields often lead to the radiation belt electron losses due to pitch-angle scattering. We show that, for the present event, the EMIC waves are not responsible for scattering electrons into a loss cone, and thus, they are unlikely to be responsible for the observed microinjection signature. We also find that the parallel electric field potentials within the waves are not adequate to explain the observed electrons with >90 keV energies. While whistler waves may contribute to the electron scattering and may exist during this event, there was no burst mode data available to verify this. 

We present the photometric and spectroscopic analysis of five Type Ibn supernovae (SNe): SN 2020nxt, SN 2020taz, SN 2021bbv, SN 2023utc, and SN 2024aej. These events share key observational features and belong to a family of objects similar to the prototypical Type Ibn SN 2006jc. The SNe exhibit rise times of approximately 10 days and peak absolute magnitudes ranging from −16.5 to −19 mag. Notably, SN 2023utc is the faintest Type Ibn SN discovered to date, with an exceptionally lowr-band absolute magnitude of −16.4 mag. The pseudo-bolometric light curves peak at (1 − 10)×10⁴²erg s⁻¹, with total radiated energies on the order of (1 − 10)×10⁴⁸erg. Spectroscopically, these SNe display a relatively slow spectral evolution. The early spectra are characterised by a hot blue continuum and prominent He Iemission lines. The early spectra also show blackbody temperatures exceeding 10 000 K, with a subsequent decline in temperature during later phases. Narrow He Ilines, which are indicative of unshocked circumstellar material (CSM), show velocities of approximately 1000 km s⁻¹. The spectra suggest that the progenitors of these SNe underwent significant mass loss prior to the explosion, resulting in a He-rich CSM. Our light curve modelling yielded estimates for the ejecta mass (M_ej) in the range 1 − 3 M_⊙with kinetic energies (E_Kin) of (0.1 − 1)×10⁵⁰erg. The inferred CSM mass ranges from 0.2 to 1 M_⊙. These findings are consistent with expectations for core collapse events arising from relatively massive envelope-stripped progenitors. 

Abstract Both ground based magnetometers and ionospheric radars at Earth have frequently detected Ultra Low Frequency (ULF) fluctuations at discrete frequencies extending below one mHz‐range. Many dayside solar wind drivers have been convincingly demonstrated as driver mechanisms. In this paper we investigate and propose an additional, nightside generation mechanism of a low frequency magnetic field fluctuation. We propose that the Moon may excite a magnetic field perturbation of the order of 1 nT at discrete frequencies when it travels through the Earth's magnetotail 4–5 days every month. Our theoretical prediction is supported by a case study of ARTEMIS magnetic field measurements at the lunar orbit in the Earth's magnetotail. ARTEMIS detects statistically significant peaks in magnetic field fluctuation power at frequencies of 0.37–0.47 mHz that are not present in the solar wind. 

A flag is a nested sequence of vector spaces. The type of the flag encodes the sequence of dimensions of the vector spaces making up the flag. A flag manifold is a manifold whose points parameterize all flags of a fixed type in a fixed vector space. This paper provides the mathematical framework necessary for implementing self-organizing mappings on flag manifolds. Flags arise implicitly in many data analysis contexts including wavelet, Fourier, and singular value decompositions. The proposed geometric framework in this paper enables the computation of distances between flags, the computation of geodesics between flags, and the ability to move one flag a prescribed distance in the direction of another flag. Using these operations as building blocks, we implement the SOM algorithm on a flag manifold. The basic algorithm is applied to the problem of parameterizing a set of flags of a fixed type.