Caty Pilachowski IUB Astronomy Telescopes: From Galileo to Hi-Tech Giants Mini-University 2005

Beginnings… This sketch of a telescope was included in a letter written by Giovanpattista della Porta in August 1609

Thomas Harriet’s Drawings of the Moon and Sun

 Invented by the Scottish mathematician James Gregory in the early 1660s  Newton communicated the details of his telescope to the Royal Society in 1670 Newton and his Reflecting Telescope

Telescopes and how they work from lenses… to mirrors

Technology moves forward…

The 3.5-meter WIYN telescope Kitt Peak, Arizona

New Telescope Technology  “Fast” mirror  Lightweight mirror  Mirror shape controlled  Mechanically simpler mount  Temperature control

Casting the WIYN Mirror

Polishing the WIYN Mirror

The WIYN New Technology “Dome”  Compact telescope chamber  Open for ventilation  Insulated to keep cool  Heated spaces kept separate

Breaking the “cost curve” New technology provides better performance at lower cost WIYN

in 6-8 meter telescopes WIYN TECHNOLOGY

8-10 Meter Telescopes Today  Keck Telescopes  Gemini North and South  ESO’s Very Large Telescope  Subaru  Hobby-Eberly Telescope and SALT  MMT Observatory  Magellan  Large Binocular Telescope

The Twin Keck Telescopes on Mauna Kea  Two 10-meter telescopes  “segmented” mirrors  36 hexagonal segments  Keck I in 1993; Keck II in 1996

ESO’s VLT Cerro Paranal, Chile Four 8.2 meter telescopes  Antu (the Sun)  Kueyen (the Moon)  Melipel (the Southern Cross)  Yepun (Venus - as evening star)

Subaru on Mauna Kea  Built by Japan  8.2-meter mirror  supported on air  superb images

New technology telescopes give new views of the universe  How is the Universe put together?  What is the Universe made of?  Is there life elsewhere?

How is the Universe put together?  The Wilkinson Microwave Anisotropy Probe tells us about the state of the Universe 400,000 years after the Big Bang. How did the Universe evolve from this…

…to this?

The cosmic web of intergalactic gas and galaxies in a young universe Intergalactic gas Clumps concentrated by dark matter lead to galaxies Observing the assembly of galaxies Galaxy building blocks observed with Hubble Simulation

WMAP also provides evidence of the first stars  Tiny fluctuations in polarization  About 200 million years after the Big Bang

Can we see the first stars? Simulation To “see” the first stars, we need a 30-m telescope! (Barton et al., 2004) 4 million LY hydrogen emission from hot stars Green=hot gasyellow=stars

The composition of stars and gas: everything else 90% hydrogen atoms 10% helium atoms Less than 1% everything else What is the Universe made of?

But ordinary matter is only part of the story… 96% of the Universe is something else

Galaxy interactions require more mass than we can see Antennae Galaxy (HST) Computer simulation The real thing

Dark Matter  The universe contains additional matter we cannot see  Dark matter interacts with normal matter through gravity  Dark matter does NOT interact with light the way the normal matter does  The Universe contains 5 or 6 times MORE dark matter than normal matter  All galaxies are embedded in clouds of dark matter  We do not know what it is!

“Redshift” of Galaxies  The spectra of galaxies are shifted to the red: galaxies are moving away from us.  The farther away a galaxy is, the faster it recedes from us!

Hubble’s Law

The speeds of very distant galaxies tell us the Universe is expanding faster today than in the past The brightness of stellar explosions tells us how far away galaxies are

The universe is expanding faster today than it did in early times This expansion cannot be caused by ordinary or dark matter, which slows expansion. The acceleration suggests a new repulsive force (anti-gravity) acting on very large scales The Universe is speeding up!

 Dark energy accounts for 73% of the content of the universe  Dark matter accounts for 23%  The content we’re familiar with is only 4% The New Force Is Called “Dark Energy”

 We don’t know What is Dark Energy? Identifying what dark energy is requires bigger telescopes and new techniques

Is there life elsewhere? Artist’s conception of 55 Cancri’s planetary system More than 150 planets found around other stars Most are vastly different from our Solar System

 detecting planets directly is hard  planets are small and dim  planets are near much brighter stars  detecting planets directly requires large telescopes (30-meters) and/or special instruments Detecting Planets

 text The importance of image quality typical ground- based image Hubble image WIYN image The Ring Nebula

Adaptive Optics – Correcting distortions caused by the Earth’s Atmosphere

How does it work???

UH-88”, Courtesy W.Brandner, 0.65” seeing 4’ 40” 5” >220 stars in 5”x5” Gemini N/Hokupa’a-QUIRC (U of H/NSF) The Power of Adaptive Optics

An exoplanet orbits a brown dwarf “star” at a distance of about 55 AU (the star and planet are about 200 light years away) From the ESO Very Large Telescope

Imaging planets around other stars “Brown Dwarf” orbiting a star at the same distance as Saturn from our Sun Gemini/Keck AO detection by Michael Liu (IfA), 2002

With a 30-meter telescope we can obtain the spectra of planets around other stars to search for the signatures of life Simulation by Sudarsky et al Simulation of the spectra of 55 Cancri’s planets

Connecting the First Nanoseconds to the Origin of Life

New Telescopes to Answer New Questions  30-meter telescope  8-meter survey telescope  James Webb Space Telescope  Virtual Observatory

The giant, segmented-mirror telescope To study the formation of the first stars and galaxies will require a new generation of larger telescopes Bigger than a football field! JWST

 8.4-meters  Triple-fold optical design  3 billion pixel-camera  30,000 gigabytes each night LSST Large-aperture Synoptic Survey Telescope  Survey the sky each week  Real-time data analysis  3 billion sources + transients

Exploring the Dark Universe with LSST

WIYN and the Future: ODI  One Degree Imager  1 billion pixels:  32,000 x 32,000 pixels  “on chip” image correction

ODI in the Astronomical Landscape The best wide-field imager, current or planned Diagnostic Imaging Information rate 2nd only to LSST (in 2012+) Image quality  median seeing 0.7”  sampling 0.11”  image correction Time resolution  2-4s readouts  faster for small regions

IU Science with ODI  Star clusters and stellar evolution  The history of nearby galaxies  Surveys of faint and distant galaxies

Beyond 30-meters ESO’s Overwhelmingly Large Telescope

Websites of Interest  Indiana Astronomical Society   National Optical Astronomy Observatory Image Gallery   Hubble Space Telescope Images   Amazing Space  amazing-space.stsci.edu amazing-space.stsci.edu  NASA’s Astronomy Picture of the Day  antwrp.gsfc.nasa.gov antwrp.gsfc.nasa.gov  Astronomical Society of the Pacific   The Stonebelt Stargazers 