1. Modern Telescopes and Ancient Skies New Views of the Universe An IU Lifelong Learning Class Tuesdays, May 10, 17, 24 II. Space Telescopes

2. 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

3. Electromagnetic Spectrum

4. Hubble Trivia  Launched April 24, 1990, by Space Shuttle Discovery  First space-based visible- light telescope  Also ultraviolet and near- infrared  Orbits about 380 miles (611 km) above Earth  Named after astronomer Edwin Hubble  discovered galaxies beyond our Milky Way  determined that space is expanding

5. More Hubble Trivia  The size of a school bus  43.5 feet (13.3 m) long  “weighs” more than 12 tons (11,000 kg)  Primary mirror 94.5 inches wide (2.4 m)  The wings are solar panels that power the spacecraft’s instruments

6. Keeping track of Hubble  Where is Hubble now?  When can I see Hubble? hubblesite.org/fun_.and._games www.heavens-above.com

7. Hubble’s greatest achievements  Dark Energy  Age of the Universe  Baby galaxies  Chemical makekup of extra-solar planets  Black holes in galaxies  Powerful stellar explosions  Source of quasar light  Forming Planets  Comet impact on Jupiter  Deaths of stars Beginning with Dark Energy

8. What is the Universe made of? Ordinary matter is only part of the story… 96% of the Universe is something else

9. “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!

10. Hubble’s Law

11. 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

12. Space and Ground in Partnership  Supernova brightness measure with Hubble  Velocities measured from the ground

13. 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!

14.  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”

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

16. The Age of the Universe  One of Hubble's key observations  Cepheid variable stars in the Virgo cluster  Hubble narrowed the age to 13 - 14 billion years

17. Baby Galaxies  Deepest images of the most distant galaxies  A scrapbook of the early universe  Hubble images reveal "toddler" galaxies 400 to 800 million years after the Big Bang  Unlike the Milky Way, baby galaxies take many shapes  toothpicks  links on a bracelet  Hubble lets us witness how galaxies form  By studying galaxies at different eras, we can see how galaxies change over time. Hubble Deep Fields Great Observatories Origins Deep Survey Hubble Ultra Deep Field

18. Planets around other stars  Ground-based telescopes find planets  Hubble can measure their chemical makeup  sodium, hydrogen, carbon, and oxygen in the atmosphere of a Jupiter-sized planet  Does life exist on extra-solar planets?  Hubble also measured the masses of two distant worlds  One is the oldest known planet - 13 billion years

19. Monster Black Holes  The centers of galaxies contain black holes with masses millions to billions times that of our Sun  Big galaxies contain big black holes, small galaxies have mall black holes  Black holes may grow with their galaxies, feasting on gas and stars swirling around the hearts of those galaxies.

20. Biggest Booms  Hubble showed that these brief, bright flashes come from distant galaxies forming stars at enormously high rates  The "bursts“ are the collapse of massive stars  A nearby gamma ray burst would burn away the ozone in Earth's atmosphere Gamma ray bursts are the most powerful explosions in the universe

21. Quasar Light  Hubble tracked down the "homes" of quasars, proving that these dynamos reside in the centers of galaxies  Quasars are massive black holes swallowing stars and has from their host galaxies Quasars are no larger than our solar system but outshine galaxies of hundreds of billions of stars.

22. Building Planets  Hubble discovered that many young stars are surrounded by flattened disks of gas and dust  These disks, now known as "proplyds" (short for protoplanetary disks), are the likely birthplaces of new planetary system  Hubble provided visual proof that pancake-shaped dust disks around young stars are common, suggesting that the building blocks for planet formation are in place.

23. Comet Impact  In 1994, two dozen chunks of Comet Shoemaker- Levy 9 smashed into Jupiter  Hubble captured the massive explosions that sent towering mushroom-shaped fireballs of hot gas into the Jovian sky  Each impact left temporary black sooty scars in Jupiter's planetary clouds.

24. Stellar Deaths Planetary Nebulae: A Sun-like star's death is a colorful event. Such stars die gracefully by ejecting their outer gaseous layers into space. The outer layers glow in vibrant colors of red, blue, and green. Hubble revealed the details of this process, showing that the shapes of planetary nebulae are quite complex. Supernovae: Massive stars end in glorious explosions. Hubble found three mysterious rings of material encircling a doomed star that exploded as a supernova in 1987. During the years since the eruption, Hubble spied brightened spots on the middle ring caused by material ejected from the explosion slamming into it.

25. Even More Hubble Trivia  Hubble has taken more than 700,000 exposures and probed more than 22,000 celestial objects.  Hubble has whirled around Earth nearly 88,000 times, racking up 2.3 billion miles.  The telescope's observations have produced 23 terabytes of data, equal to the amount of text in 23 million novels. The Hubble data would fill two Library of Congress book collections.  In Hubble's 15-year lifetime, about 3,900 astronomers from all over the world have used the telescope to probe the universe.  Astronomers have published more than 4,000 scientific papers on Hubble

26. The Hubble Space Telescope

27. The Chandra X-Ray Telescope

28. 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.

29.  Chandra flies 200 times higher than Hubble - more than 1/3 of the way to the moon!  Chandra can observe X-rays from clouds of gas so vast that it takes light five million years to go from one side to the other!  During maneuvers from one target to the next, Chandra slews more slowly than the minute hand on a clock.  At 45 feet long, Chandra is the largest satellite the shuttle has ever launched!  If Colorado were as smooth as Chandra's mirrors, Pikes Peak would be less than one inch tall!  Chandra's resolving power is equivalent to the ability to read a stop sign at a distance of twelve miles.  The electrical power required to operate the Chandra spacecraft and instruments is 2 kilowatts, about the same power as a hair dryer.  Chandra can observe X-rays from particles up to the last second before they fall into a black hole!!! Chandra Factoids

30.  Chandra studies x-ray flares in Orion solar mass stars  Early solar flares ionized protoplanetary disk, induced turbulence that may have “saved” the Earth from migrating into the Sun X-Rays from Young Suns

31.  X-rays from Cygnus X-1 come from as close as 20- 100 miles from the black hole, but it does not seem to be spinning  Chandra observations of another stellar black hole, GX 339-4, indicate that it is spinning rapidly A spinning black hole drags space around with it X-Rays from Black Holes

32. The Center of the Milky Way in X-Rays  Chandra observed matter falling toward the black hole at the center of the Milky Way  X-Ray flare from material close to the black hole

33. The Spitzer Infrared Space Telescope

34. Spitzer Trivia  Launched 25 August 2003  Delta rocket from Cape Canaveral  Estimated Lifetime:2.5 – 5 years  Orbits the Sun, Earth-trailing, heliocentric  Wavelength Coverage: 3 - 180 microns  Telescope - 85 cm diameter (33.5”)  f/12 lightweight beryllium mirror, cooled to less 5.5 K

35. Infrared Views of Familiar Objects

36. Spitzer Studies Star Formation

37. Spitzer Teachers

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

39. Kirkwood Observatory Viewing  Tuesday evenings, weather permitting

40. Night Sky Viewing Scheduled nights –Tuesday, May 17 –Tuesday, May 24 Roof of Swain West

41. Next Week Giant Telescopes New Views of the Universe – Planets around other Suns Kirkwood Obs and Rooftop, weather permitting