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

摘要

This paper on ASTROD I is based on our 2010 proposal submitted for the ESAcall for class-M mission proposals, and is a sequel and an update to ourprevious paper [Experimental Astronomy 23 (2009) 491-527; designated as PaperI] which was based on our last proposal submitted for the 2007 ESA call. Inthis paper, we present our orbit selection with one Venus swing-by togetherwith orbit simulation. In Paper I, our orbit choice is with two Venusswing-bys. The present choice takes shorter time (about 250 days) to reach theopposite side of the Sun. We also present a preliminary design of the opticalbench, and elaborate on the solar physics goals with the radiation monitorpayload. We discuss telescope size, trade-offs of drag-free sensitivities,thermal issues and present an outlook. ASTROD I is a planned interplanetaryspace mission with multiple goals. The primary aims are: to test GeneralRelativity with an improvement in sensitivity of over 3 orders of magnitude,improving our understanding of gravity and aiding the development of a newquantum gravity theory; to measure key solar system parameters with increasedaccuracy, advancing solar physics and our knowledge of the solar system; and tomeasure the time rate of change of the gravitational constant with an order ofmagnitude improvement and the anomalous Pioneer acceleration, thereby probingdark matter and dark energy gravitationally. It is envisaged as the first in aseries of ASTROD missions. ASTROD I will consist of one spacecraft carrying atelescope, four lasers, two event timers and a clock. Two-way, two-wavelengthlaser pulse ranging will be used between the spacecraft in a solar orbit anddeep space laser stations on Earth, to achieve the ASTROD I goals.