Observational Astronomy

Astronomy Primary Goal: Understanding the nature of the universe and its constituents Means: Equipment building, research, teaching

General Areas of Study Solar – the study of the sun Planetary – the study of planets, comets, asteroids, debris around other stars Stellar – the study of stars Galactic – the study of our Galaxy Extragalactic – the study of other galaxies Cosmology – the study of the origin & evolution of the universe

Research – Scientific Detective Work Hypothesis Tools/Sample to Test Hypothesis Propose for Observations Obtain Observations Reduce & Analyze data Modify Hypothesis Etc.

The “Laboratory” for Observational Astronomy Ground-based and Space-based Telescopes Computers - for processing data The internet - for transferring and sharing data, access to journals, etc. The classroom - where ideas are shared and developed with the next generation of astronomers

Good Observing Site Minimal number of cloudy nights Minimal atmospheric turbulence Away from bright lights / cities Low water vapor

Telescopes are thus located on Mountaintops Mauna Kea Observatories, located on Mauna Kea on the Big Island of Hawaii Elevation above sea level = 13,800 ft

… In Desert Valleys… Owens Valley, California

… and in Space The “Seeing” at various sites:Long Island, NY: > 5” Kitt Peak, AZ: ~ 1.5” Mauna Kea, HI: ~ ” HST: 0.05” Note: 60” = 1’ 60’ = 1 o

Not all wavelengths of light hit the ground This is one reason why some air/space-borne missions are necessary

Observing on Mauna Kea Observers sleep at a dormitory located at 10,000 ft Then drive to summit with the telescope operator 2 persion rule - due to dangers of working at altitude

Mauna Kea with Maui in the distance Clouds typically are below 10,000 ft

The United Kingdom Infrared Telescope

Gemini Telescope on Mauna Kea Secondary Mirror Primary Mirror (8m Aperture)

Sunset on Mauna Kea – Gemini Telescope Open air design of the dome helps to reduce air turbulence in the dome Secondary Mirror Primary Mirror

UKIRT Detectors are mounted behind the primary

Observing Most ground-based observational astronomy is done at night Observers are assisted by telescope operators and support scientist

Observing  Some observations are done quasi-remotely (e.g., Keck)  … Or very remotely (I.e., space based telescopes)

Observing  Some observations are done during the day  Sometimes the observers is the telescope operator

Potential Problems CloudsIce Software/Hardware Malfunctions

Support for Observational Astronomy National Aeronautics & Space Administration (NASA) National Science Foundation (NSF) Private Donors

Exciting Discoveries over the Last ~ 10 Years - The Kuiper Belt & its Bearing on the Nature of Pluto Extrasolar Planets Supermassive Black Holes in Nearby Normal Galaxies Galaxies at High Redshift

Goals for the Next 10 Years Survey the universe & its constituents Use the universe as a unique lab for probing the laws of physics not accessible on Earth Search for life beyond Earth, & if it is found, determine its nature & its distribution Develop a conceptual framework that account for all that astronomers have observed