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In April 2023, low-latitude aurora observation by the all-sky camera at Hanle, Ladakh, India ($33^{\circ} {} N $ geographic latitude (GGLat)) was reported, which stimulated a lot of discussion among scientists as well as masses across the globe. The reported observation was intriguing as the solar storm that triggered this aurora was moderate and the first such observation from Indian region in the space-era. In this communication, we investigate such a unique modern-day observation of low-latitude auroral sighting occurring during the passage of sheath-region of Interplanetary-Coronal-Mass-Ejection, utilizing in situ multi-spacecraft particle measurements along with geomagnetic-field observations by ground and satellite-based magnetometers. Auroral observations at Hanle coincided with the intense substorm occurrences. It is unequivocally found that the aurora didnt reach India, rather the equatorward boundary of the aurora was beyond $ 50^{\circ} {}N $ GGLat. The multi-instrumental observations enabled us to estimate the altitude of the red auroral emissions accurately. The increased flux of low-energy electrons ($<$100 eV) precipitating at $\sim 54^{\circ}N$ GGLat causing red-light emissions at higher altitudes ($\sim$700-950 km) can be visible from Hanle. The observed low-latitude red aurora from India resulted from two factors: emissions at higher altitudes in the auroral oval and a slight expansion of the auroral oval towards the equator. The precipitating low-energy particles responsible for red auroral emissions mostly originate from the plasma sheet. These particles precipitate due to wave-particle interactions enhanced by strong compression of the magnetosphere during high solar wind pressure. This study using multi-point observations holds immense importance in providing a better understanding of low-latitude auroras., Comment: 18 pages, 10 Figures, 1 Table, 2 supplementary figures

Nowadays smartphones come embedded with multiple motion sensors, such as an accelerometer, a gyroscope and an orientation sensor. With these sensors, apps can gather more information and therefore provide end users with more functionality. However, these sensors also introduce the potential risk of leaking a user's private information because apps can access these sensors without requiring security permissions. By monitoring a device's motion, a malicious app may be able to infer sensitive information about the owner of the device. For example, related work has shown that sensitive information entered by a user on a device's touchscreen, such as numerical PINs or passwords, can be inferred from accelerometer and gyroscope data. In this paper, we study these motion-based keystroke inference attacks to determine what information they need to succeed. Based on this study, we propose two novel approaches to defend against keystroke inference attacks: 1) Reducing sensor data accuracy; 2) Random keyboard layout generation. We present the design and the implementation of these two defences on the Android platform and show how they significantly reduce the accuracy of keystroke inference attacks. We also conduct multiple user studies to evaluate the usability and feasibility of these two defences. Finally, we determine the impact of the defences on apps that have legitimate reasons to access motion sensors and show that the impact is negligible., Comment: In Proceedings of the Third Workshop on Mobile Security Technologies (MoST) 2014 (http://arxiv.org/abs/1410.6674)

Experiments on the oscillatory motion of a suspended bar magnet throws light on the damping effects acting on the pendulum. The viscous drag offered by air was found the be the main contributor for slowing the pendulum down. The nature and magnitude of the damping effects were shown to be strongly dependent on the amplitude., Comment: 19 pages with 11 figures. Submitted to AJP