The Future of Cosmology Ay21, March 10, 2010 Announcements: final exams available beginning 9am on March 12 (Friday), from Swarnima (note that the final will not be distributed electronically). finals are due no later than 5pm on Weds. March 17, in Steidel s mailbox in 249 Cahill. Future Directions Planned dark energy large Type Ia supernova surveys (in space?) weak gravitational lensing statistics (in space?) Baryon Acoustic Oscillations Counting galaxy clusters vs. redshift origin of structure microwave background galaxy formation dark matter mapping black hole demographics the first sources of light in the Universe gravity wave background Unplanned (sure to be the most interesting!) 1
Future Directions Dark Energy: Joint Dark Energy Mission (in planning stages...) Focus is mainly on LARGE surveys for Type Ia supernovae (either on ground or in space) Supernova Acceleration Probe (SNAP) Idea is to trace dark energy evolution using supernovae, and dark matter using weak gravitational lensing Wide field imager in space, with some spectroscopic capability Cosmic Concordance 2
Future Directions Dark Energy: trying to establish whether the dark energy density changes with time (n.b. - it s going to be hard) Future Directions Origin and Evolution of Structure in the Universe: future microwave background experiments Planck will improve on current experiments in precision with which cosmological parameters can be read off the temperature fluctuation maps Will also produce an all-sky map of early galaxy clusters via the Sunyaev-Zeldovich effect New holy grail : measuring polarization of CBR, signature of gravity waves predicted by inflation. Planck Surveyor: All Sky survey with 5 arcmin resolution+ many frequencies There are at least a dozen planned experiments for measuring polarization... 3
Future Directions Origin and Evolution of Structure in the Universe: The first sources of light in the universe James Webb Space Telescope 6-meter aperture IRoptimized (esp. 1-5 microns) space telescope ( successor to Hubble ) Supreme sensitivity to the faintest objects at the earliest cosmic times (exploring the Dark Ages ) The Star Formation History of the Universe SFR/co-moving volume You are here The enlightenment? The Dark Ages Billion Years Ago 11 14 4
Diffraction-Limited Observing from the Ground: The Adaptive Optics Revolution Mauna Kea and Laser Guide Stars 5
Adaptive Optics: How it Works NGC 1569 SSC B Hubble NIC2 F160W (Field of view: 6 x 6 ) 15 pc 6
NGC 1569 SSC B Keck AO IHK (Field of view: 6 x 6 ) 15 pc 7
Primary Mirror: 492 1.4m segments TMT: Fast Facts 30 meter (98-ft) diameter, filled aperture, 492-segment primary mirror Three-mirror telescope f/1 primary Field of view 20 arcminute Site: Mauna Kea, HI Wavelength 0.31 28 µm Fully integrated adaptive optics Partners: Caltech, UC, Canada, Japan, (India, China) 16 8
Origin and Evolution of Structure in the Universe: Galaxy formation: current large ground-based telescopes, the Atacama large millimeter array, and next generation groundbased telescopes, like: Thirty Meter Telescope (TMT) (www.tmt.org) UC, Caltech, Canada, Japan, + First light: 2018 9
3-D Spectroscopy Using Integral Field Optics Tomography of the Distant Universe Idea is to map the whole web of structure when the universe was young, during the peak of galaxy formation 10
Future Directions Origin and Evolution of Structure in the Universe: Atacama Large Millimeter Array (ALMA), Chajnantor Plateau (16,000 ft), Chile www.alma.nrao.edu Future Directions The Time Domain: Largely Unexplored! Goal is to map the entire observable sky once every few days, to faint levels new phenomena are guaranteed Large Synoptic Survey Telescope (LSST; ~2015-16?) 11
Future Directions The Real Dark Ages (z>zreion): only game in town is HI (neutral H). The Square Kilometer Array (SKA) early universe using 21cm transition Need 1 km2 collecting area, with >100 km baseline (for better than 1 resolution) The Importance of Serendipity in Astronomy... If you examine the original documents used to justify astronomical facilities, instruments, and observatories, almost all of the most exciting science that eventually was done was completely unanticipated one is always projecting based on what one knows now, which will not last long in its current form Other historical comments: when people have thought that everything is understood they have almost always been very wrong! we will be surprised by future developments the universe is extremely unpredictable 12