Trojan

About: Trojan is a research topic. Over the lifetime, 2028 publications have been published within this topic receiving 33209 citations.

Lucy: Navigating a Jupiter Trojan Tour

Abstract: In January 2017, NASA selected the Lucy mission to explore six Jupiter Trojan asteroids. These six bodies, remnants of the primordial material that formed the outer planets, were captured in the Sun-Jupiter L4 and L5 Lagrangian regions early in the solar system formation. These particular bodies were chosen because of their diverse spectral properties and the chance to observe up close for the first time two orbiting approximately equal mass binaries, Patroclus and Menoetius. KinetX, Inc. is the primary navigation supplier for the Lucy mission. This paper describes preliminary navigation analyses of the approach phase for each Trojan encounter.

Studying the jovian Trojan dust

Abstract: Aims. We analyze the jovian Trojan dust in the L4 swarm. Methods. To do this, we use a modification of the numerical code developed by us and previously applied to the collisional and dynamical evolution of the L4 jovian Trojans. This algorithm considers catastrophic collisions and cratering events, includes a dynamical treatment that takes the stability and instability zones of the L4 jovian swarm into account, and incorporates the effects of the Poynting-Robertson radiation. Results. From this analysis, we infer that the time evolution of the L4 jovian Trojan dust luminosity has the characteristics of a diffusion process, since its current value is fairly insensitive to variations in the initial size distribution. Moreover, our results indicate that the current luminosity of the dust in the L4 jovian swarm ranges from ∼3.2 × 10 −8 to 3.4 × 10 −8 L� . Conclusions. From these estimates, we conclude that the current luminosity of the dust in the L4 jovian swarm is comparable to the luminosity of the inner Solar System dust, and, at least, one order of magnitude lower than the luminosity of the outer Solar System dust.

A Security-Aware Pre-partitioning Technique for 3D Integrated Circuits

Abstract: Outsourcing the chip for fabrication is an efficient way to save money and reduce time to market. However, it raises numerous security challenges for chip designers, as some of the foundries try to identify the functionality of the chip to take its ownership. Furthermore, some foundries may insert a Trojan circuit to affect the functionality of the chip or steal valuable information about the design such as encryption key. Each Trojan may utilize low toggle (LT) nets to trigger its activation [1]. Hence, it is tough to detect a Trojan circuit during the testing step as it lies dormant for ages and waits until its rare activation conditions are met. Consequently, some mechanisms are required to neutralize the attacker's plans for inserting a Trojan circuit. 3D Integrated circuit (3D-IC) can be a practical solution to the challenges that threaten the security of the chip. One of the famous features of 3D-IC is its capability of split manufacturing of the chip, as the whole design can be distributed among different tiers in the 3D stack. Tiers containing critical logic blocks are sent to a trusted local foundry to be fabricated while the less significant tiers are sent to the less reliable foundries to save money. In this work, we propose a method to sabotage the trigger criteria for a hardware Trojan. To do so we obscure root LT nets by replacing each of them with a vertical interconnect known as Through Silicon Via (TSV) in a 3D-IC structure. A root (earliest ancestor) LT net is defined as a net that is the origin of other LT nets. As we will discuss in section IV, obscuring a root LT net will result in hiding the toggle characteristics of its offspring LT nets. Therefore, untrusted foundries will not be able to exploit LT nets for activating their Trojan circuits. They may even use the high toggle nets for enabling the Trojan circuit. Thus, the chance of Trojan circuit getting compromised during the testing process will be high. In the end, list of root LT nets obtained from our algorithm will be used in upcoming partitioning stage to boost the security of the design.

Comparison of the Physical Properties of the L4 and L5 Trojan Asteroids from ATLAS Data

Abstract: Jupiter has nearly 8000~known co-orbital asteroids orbiting in the L4 and L5 Lagrange points called Jupiter Trojan asteroids. Aside from the greater number density of the L4 cloud the two clouds are in many ways considered to be identical. Using sparse photometric data taken by the Asteroid Terrestrial-impact Last Alert System (ATLAS) for 863 L4 Trojans and 380 L5 Trojans we derive the shape distribution for each of the clouds and find that, on average, the L4 asteroids are more elongated than the L5 asteroids. This shape difference is most likely due to the greater collision rate in the L4 cloud that results from its larger population. We additionally present the phase functions and $c-o$ colours of 266~objects.