Taking the Measure of the Universe: Precision Astrometry with SIM PlanetQuest

Abstract

Precision astrometry at microarcsecond accuracy has application to a wide range of astrophysical problems. This paper is a study of the science questions that can be addressed using an instrument that delivers parallaxes at about 4 microarcsec on targets as faint as V = 20, differential accuracy of 0.6 microarcsec on bright targets, and with flexible scheduling. The science topics are drawn primarily from the Team Key Projects, selected in 2000, for the Space Interferometry Mission PlanetQuest (SIM PlanetQuest). We use the capabilities of this mission to illustrate the importance of the next level of astrometric precision in modern astrophysics. SIM PlanetQuest is currently in the detailed design phase, having completed all of the enabling technologies needed for the flight instrument in 2005. It will be the first space-based long baseline Michelson interferometer designed for precision astrometry. SIM will contribute strongly to many astronomical fields including stellar and galactic astrophysics, planetary systems around nearby stars, and the study of quasar and AGN nuclei. SIM will search for planets with masses as small as an Earth orbiting in the `habitable zone' around the nearest stars using differential astrometry, and could discover many dozen if Earth-like planets are common. It will be the most capable instrument for detecting planets around young stars, thereby providing insights into how planetary systems are born and how they evolve with time. SIM will observe significant numbers of very high- and low-mass stars, providing stellar masses to 1%, the accuracy needed to challenge physical models. Using precision proper motion measurements, SIM will probe the galactic mass distribution and the formation and evolution of the Galactic halo. (abridged)

54 pages, 28 figures, uses emulateapj. Submitted to PASP

References in corpus (7)

• Report of the Dark Energy Task Force
• The Mira variable S Ori: Relationships between the photosphere, molecular layer, dust shell, and SiO maser shell at 4 epochs
• Determining the Nature of Dark Matter with Astrometry
• The Araucaria Project. The Distance to the Sculptor Group Galaxy NGC 55 from a Newly Discovered Abundant Cepheid Population
• VLA+PT Astrometry of 46 Radio Stars
• Finding Solar System Analogs With SIM and HIPPARCOS: A White Paper for the ExoPlanet Task Force
• Relativistic stellar aberration for the Space Interferometry Mission

Cited by in corpus (13)

• Double-blind test program for astrometric planet detection with Gaia
• M31 Transverse Velocity and Local Group Mass from Satellite Kinematics
• Habitable Climates
• Natural Transfer of Viable Microbes in Space from Planets in the Extra-Solar Systems to a Planet in our Solar System and Vice-Versa
• Precision Astrometry with Adaptive Optics
• Overview of the SIM PlanetQuest Light (SIM-Lite) mission concept
• Proper Motion of Milky Way Dwarf Spheroidals from Line-of-Sight Velocities
• Relativistic gravitational deflection of light and its impact on the modeling accuracy for the Space Interferometry Mission
• The complementarity of astrometric and radial velocity exoplanet observations - Determining exoplanet mass with astrometric snapshots
• X-ray Clusters of Galaxies as Cosmological Tools
• Local effects in astrometric binary orbits: perspective transformation and light-travel time
• Astrometric effects of non-uniform telescope throughput
• Probing the Galactic Potential with Next-Generation Observations of Disk Stars