Astrodynamical Space Test of Relativity using Optical Devices I (ASTROD I) - A class-M fundamental physics mission proposal for Cosmic Vision 2015-2025: 2010 Update

This paper on ASTROD I is based on our 2010 proposal submitted for the ESA call for class-M mission proposals, and is a sequel and an update to our previous paper [Experimental Astronomy 23 (2009) 491-527; designated as Paper I] which was based on our last proposal submitted for the 2007 ESA call. In this paper, we present our orbit selection with one Venus swing-by together with orbit simulation. In Paper I, our orbit choice is with two Venus swing-bys. The present choice takes shorter time (about 250 days) to reach the opposite side of the Sun. We also present a preliminary design of the optical bench, and elaborate on the solar physics goals with the radiation monitor payload. We discuss telescope size, trade-offs of drag-free sensitivities, thermal issues and present an outlook. ASTROD I is a planned interplanetary space mission with multiple goals. The primary aims are: to test General Relativity with an improvement in sensitivity of over 3 orders of magnitude, improving our understanding of gravity and aiding the development of a new quantum gravity theory; to measure key solar system parameters with increased accuracy, advancing solar physics and our knowledge of the solar system; and to measure the time rate of change of the gravitational constant with an order of magnitude improvement and the anomalous Pioneer acceleration, thereby probing dark matter and dark energy gravitationally. It is envisaged as the first in a series of ASTROD missions. ASTROD I will consist of one spacecraft carrying a telescope, four lasers, two event timers and a clock. Two-way, two-wavelength laser pulse ranging will be used between the spacecraft in a solar orbit and deep space laser stations on Earth, to achieve the ASTROD I goals.Comment: 15 pages, 11 figures, 1 table, based on our 2010 proposal submitted for the ESA call for class-M mission proposals, a sequel and an update to previous paper [Experimental Astronomy 23 (2009) 491-527] which was based on our last proposal submitted for the 2007 ESA call, submitted to Experimental Astronom

Solar and cosmic ray physics and the space environment: Studies for and with LISA

With data analysis preparations for LISA underway, there has been renewed interest in studying solar, cosmic ray and environmental physics for, and using LISA. The motivation for these studies is two fold. The primary incentive is to predict and consequently minimize the impact of disturbances associated with these factors, to maximize LISA’s gravitational wave scientific yield. The second stimulus is the unique opportunity that is afforded by LISA’s long‐baseline 3‐spacecraft configuration for studies of solar, cosmic ray and environmental physics. Here we present an overview of recent progress in these studies. © 2006 American Institute of Physic

LISA Pathfinder: the experiment and the route to LISA

LISA Pathfinder (LPF) is a science and technology demonstrator planned by the European Space Agency in view of the LISA mission. As a scientific payload, the LISA Technology Package on board LPF will be the most precise geodesics explorer flown as of today, both in terms of displacement and acceleration sensitivity. The challenges embodied by LPF make it a unique mission, paving the way towards the space-borne detection of gravitational waves with LISA. This paper summarizes the basics of LPF, and the progress made in preparing its effective implementation in flight. We hereby give an overview of the experiment philosophy and assumptions to carry on the measurement. We report on the mission plan and hardware design advances and on the progress on detailing measurements and operations. Some light will be shed on the related data processing algorithms. In particular, we show how to single out the acceleration noise from the spacecraft motion perturbations, how to account for dynamical deformation parameters distorting the measurement reference and how to decouple the actuation noise via parabolic free flight