A105 Stars and Galaxies  Homework #4 due today  Telescopes  Read unit 30 for next week  News Quiz Tuesday  First Exam on Sept. 28 Today’s APODAPOD

Announcements! News Quiz on Tuesday on the new Atacama Radio Telescope First Exam on Thursday, Sept. 28 –Review Sheet as Oncourse Announcement Oncourse Update - oncourse.iu.eduoncourse.iu.edu

Special Guest!!! Professor Liese van Zee

Three types of spectra  Continuous – Thermal Radiator  Emission – from hot gas  Absorption – continuous spectrum passes through cooler gas

Electromagnetic Spectrum

Space Telescopes NASA’s four Great Observatories –Visible – Hubble Space Telescope –Gamma rays - Compton Gamma Ray Obs. –X-rays - Chandra X-ray Observatory –Infrared - Spitzer Space Telescope

Hubble Trivia Launched April 24, 1990, by Space Shuttle Discovery Visible light, ultraviolet, and near-infrared Orbits about 380 miles (611 km) above Earth About the size of a bus Primary mirror ~ 2 meters Named after astronomer Edwin Hubble –discovered galaxies beyond our Milky Way –determined that space is expanding

Keeping track of Hubble Where is Hubble now? When can I see Hubble? Where is the Hubble Space Telescope?

Space and Ground in Partnership Supernova brightness measured with Hubble Red shifts measured from the ground

The Chandra X-Ray Telescope

How Do X-Ray Telescopes Work? X-rays do not reflect off mirrors the same way that visible light does X-ray photons penetrate into the mirror in much the same way that bullets slam into a wall X-rays ricochet off mirrors like bullets off a wall X-ray telescopes are very different from optical telescopes. X-ray mirrors are precisely shaped and aligned to incoming x-rays. They look more like barrels than the familiar dish mirrors of optical telescopes.

The Spitzer Infrared Space Telescope

Spitzer Trivia Launched 25 August 2003 Estimated Lifetime:2.5 – 5 years Orbits the Sun, Earth-trailing, heliocentric Telescope – only 85 cm diameter (33.5”)

Compton Gamma Ray Observatory 1991 – 2000 solar flares gamma-ray bursts pulsars nova supernova explosions black holes quasar emission

What does it cost????? Proposed NASA budget for 2007: $16.8B –Science$5.3 billion * –Exploration$4.0 billion –Aeronautics$0.7 billion –Space Ops$6.2 billion –Education$0.15 billion * All astronomy research and space telescopes are in this part.

Comparable Spending $20 billion at jewelry stores (US) $24 billion at liquor stores (US) $40 billion on weight loss (US) $23.5 billion on candy and gum (US) $31 billion on pet toys and supplies (US) $7 billion on video rentals (US) $18 billion on makeup (worldwide) $35 billion on bottled water (worldwide)

Great Observatories’ Costs Hubble Space Telescope:$6 billion Chandra X-ray Telescope: $2.5 billion Spitzer IR Telescope: $1.2 billion Compton Gamma Ray Tel: $0.56 billion Question: Why does society chose to support science research at this cost?

The Hubble Space Telescope

Homework Review Today’s homework… Next week’s: – Check back with Hubble: Where is the Hubble Space Telescope?

 Read unit 30  News Quiz on Tuesday  NovaSearch homework (#5) worksheet due Thursday  EXAM ALSO THURSDAY