Trajectories to Nab a NEA (Near-Earth Asteroid)

In 2010 and 2011 NASA and KISS sponsored studies to investigate the feasibility of identifying, capturing, and returning an entire (albeit small) NEA to the vicinity of Earth, and concluded that a 40-kW solar electric propulsion system launched on an Atlas 551 provided sufficient propulsion to control an asteroid's trajectory. Once secured by the spacecraft, a NEA with a naturally close encounter with Earth is nudged over a few years to target a lunar gravity assist, capturing the object into Earth orbit. With further use of solar perturbations, up to 3,600,000 kg of NEA could be placed in high-lunar orbit

Enhanced Gravity Tractor Technique for Planetary Defense

Given sufficient warning time, Earth-impacting asteroids and comets can be deflected with a variety of different "slow push/pull" techniques. The gravity tractor is one technique that uses the gravitational attraction of a rendezvous spacecraft to the impactor and a low-thrust, high-efficiency propulsion system to provide a gradual velocity change and alter its trajectory. An innovation to this technique, known as the Enhanced Gravity Tractor (EGT), uses mass collected in-situ to augment the mass of the spacecraft, thereby greatly increasing the gravitational force between the objects. The collected material can be a single boulder, multiple boulders, regolith or a combination of different sources. The collected mass would likely range from tens to hundreds of metric tons depending on the size of the impactor and warning time available. Depending on the propulsion system's capability and the mass collected, the EGT approach can reduce the deflection times by a factor of 10 to 50 or more, thus reducing the deflection times of several decades to years or less and overcoming the main criticism of the traditional gravity tractor approach. Additionally, multiple spacecraft can orbit the target in formation to provide the necessary velocity change and further reduce the time needed by the EGT technique to divert hazardous asteroids and comets. The robotic segment of NASA's Asteroid Redirect Mission (ARM) will collect a multi-ton boulder from the surface of a large Near-Earth Asteroid (NEA) and will provide the first ever demonstration of the EGT technique and validate one method of collecting in-situ mass on an asteroid of hazardous size

4 th IAA Planetary Defense Conference -PDC

Abstract Given sufficient warning time, Earth-impacting asteroids and comets can be deflected with a variety of different "slow push/pull" techniques. The gravity tractor is one technique that uses the gravitational attraction of a rendezvous spacecraft to the impactor and a low-thrust, high-efficiency propulsion system to provide a gradual velocity change and alter its trajectory. An innovation to this technique, known as the Enhanced Gravity Tractor (EGT), uses mass collected in-situ to augment the mass of the spacecraft, thereby greatly increasing the gravitational force between the objects. The collected material can be a single boulder, multiple boulders, regolith or a combination of different sources. The collected mass would likely range from tens to hundreds of metric tons depending on the size of the impactor and warning time available. Depending on the propulsion system's capability and the mass collected, the EGT approach can reduce the deflection times by a factor of 10 to 50 or more, thus reducing the deflection times of several decades to years or less and overcoming the main criticism of the traditional gravity tractor approach. Additionally, multiple spacecraft can orbit the target in formation to provide the necessary velocity change and further reduce the time needed by the EGT technique to divert hazardous asteroids and comets. The robotic segment of NASA's Asteroid Redirect Mission (ARM) will collect a multi-ton boulder from the surface of a large Near-Earth Asteroid (NEA) and will provide the first ever demonstration of the EGT technique and validate one method of collecting in-situ mass on an asteroid of hazardous size.

EuroDRONE, A European unmanned traffic management testbed for U-space

EuroDRONE is an Unmanned Traffic Management (UTM) demonstration project, funded by the EU’s SESAR organization, and its aim is to test and validate key UTM technologies for Europe’s ‘U-Space’ UTM program. The EuroDRONE UTM architecture comprises cloud software (DroNav) and hardware (transponder) to be installed on drones. The proposed EuroDRONE system is a Highly Automated Air Traffic Management System for small UAVs operating at low altitudes. It is a sophisticated, self-learning system based on software and hardware elements, operating in a distributed computing environment, offering multiple levels of redundancy, fail-safe algorithms for conflict prevention/resolution and assets management. EuroDRONE focuses its work on functionalities which involve the use of new communication links, the use of vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) technology to communicate information between drones and operators for safe and effective UTM functionality. Practical demonstrations that took place in Patras/Messolonghi in 2019 are presented and show the benefits and shortcomings of near-term UTM implementation in Europe

The role of the template in prosthetically guided implantology

In prosthetically guided implantology, where ideal placement of implants is determined by the definitive restoration, the use of a radiographic/surgical template plays an essential role. This article describes how to fabricate a radiographic/surgical template to be used for radiographic diagnosis of the selected implant sites and as a guide during surgery for the insertion of the implant with correct angulation. © 2009 by The American College of Prosthodontists

A possible Italian contribution in the NASA asteroid redirect robotic mission (ARRM)

As part of its Journey to Mars strategy, NASA announced the Asteroid Redirect Mission (ARM) program, composed of the Asteroid Redirect Robotic Mission (ARRM) first and then the Asteroid Redirect Crew Mission (ARCM). In the ARRM the Asteroid Redirect Vehicle (ARV), powered by advanced Solar Electric Propulsion (SEP), is deployed to rendezvous with a large NEO, being 2008 EV5 the current reference asteroid target. The ARV will characterize the asteroid, descend, and capture a boulder from the asteroid surface. As written in the NASA Formulation Assessment and Support Team (FAST) report released in February 2016, based on radar imaging and size distribution power laws that have been seen in data from laboratory experiments and spacecraft observations of other asteroids, 2008 EV5 is expected to have 3,000-16,000 boulders with 1-5 m diameters and 360-1,300 boulders with 2-3 m diameters. Once the boulder is captured, the ARV will perform a planetary defense test, by applying the enhanced gravity tractor technique, and then fly back towards Earth to take the boulder in a stable Lunar Distant Retrograde Orbit (DRO), as the DRO that Orion, launched on SLS, will target in Exploration Mission 1 (EM-1) scheduled for 2018. The Italian Space Agency (ASI) is considering the opportunity to participate to the NASA ARM program, beginning with a possible Italian contribution to the ARRM. Options include payloads and instruments to be accommodated on the ARV (such as a stereo camera and VIS-NIR spectrometer, possibly integrated in a newly designed instrument able to produce 3D hyper spectral images, dedicated to the asteroid surface and asteroid boulder characterization, a drill for sampling asteroid material, a sounding radar to study the internal structure of the asteroid), space communications and tracking (such as the potential use of the 64 meter Sardinia Radio Telescope (SRT) for a spacecraft telecommunications and tracking demonstration of ARRM, supplementing and in collaboration with NASA's Deep Space Network), and trajectory analysis (to provide low thrust trajectory analysis of ARRM). In this paper all these options will be briefly described