AAS 212th Meeting Session Videos
Session 45: International Year of Astronomy 2009
Session 51: My Space, Your Space, and Virtual Space: New Media E/PO
Speakers:
- Jordan Raddick — 51.01. Citizen Science in the Internet Age
- Lars Lindberg Christensen — 51.02. The Portal to the Universe an IYA2009 Cornerstone Project
- Pedro Russo — 51.03. The International Year of Astronomy 2009 Websites _ Connecting IYA2009 with its Community
- Emily Lakdawalla — 51.04. Passengers on Voyages of Exploration: The Beautiful and Surprising Work Amateurs Can Do With Raw Image Data from Planetary Missions
- Fraser Cain — 51.05. The Community of Space/Astronomy Bloggers
- Adrienne J. Gauthier — 51.07. Astronomy Education and Public Outreach in Virtual Worlds
- Philip Plait — 51.08. Social Network Infiltration
- Pamela L. Gay — 51.09. New Media E/PO: Building a Digital Astronomy Community
More Details: My Space, Your Space, and Virtual Space: New Media E/PO
Session 54: The Era of Comparative Exoplanetology
Session 55: The Great Observatories Origins Deep Survey
Session 56: Imaging with the CHARA Interferometer
Session 65: SPD Hale Prize Lecture - How Solar Flares Work
Session 74: Planet Forming Disks
Session 79: JWST's Near-Infrared Camera
Session 80: Astrometry with the Hubble Space Telescope
While spectacularly successful at locating previously unknown companions to stars, the high-precision radial velocities provided by Doppler spectroscopy only provides a minimum mass, not the actual companion mass. While spectacularly successful at providing parallaxes for thousands of nearby stars, HIPPARCOS could not reliably provide 10% parallaxes for stars more distant than ~100pc. Astrometry with Hubble Space Telescope provides both.
I describe how we obtain sub-millisecond of arc precision astrometry from white-light interferometers aboard HST, the Fine Guidance Sensors, and review our reduction and analysis procedures. These permit us to essentially model a three dimensional volume of space to extract the periodic motion of interest, be it a perturbation due to an unseen companion, or a parallax.
Specific results include exoplanet masses and a hint at exoplanetary system architecture. Is coplanarity another attribute of our own Solar System not necessarily the norm for exoplanetary systems? We have made significant contributions to the cosmic distance scale. Our parallax for the Pleiades supports the validity of modern stellar interiors modeling. We now have 10% or better precision parallaxes for ten Galactic, solar-metallicty Cepheids, resulting in a Period-Luminosity relation that provides distances to the LMC and NGC 4258.
The future of space astrometry looks bright. In the short term the FGS will produce more exoplanet masses, more tests of coplanarity, and a Pop II Period-Luminosity relation. Longer-term we have the promise of a billion parallaxes from Gaia with errors of order 25 microarcseconds and thousands at the 4 microarcsecond level from SIM. In the exoplanetary arena, Gaia will determine masses down to Neptune and test coplanarity for hundreds of systems. SIM, with narrow-angle microarcsecond precision, could find the first Earth-mass companions around the nearest stars.
Past and present research depends on support from numerous NASA grants from STScI and/or JPL, all gratefully acknowledged.