The tools

Hot question of Galileo’s time what’s at the centre: earth or sun?

Sun-centered universe Galileo’s observations. 1. The Moon’s surface Moon not a perfect “heavenly body”

Sun-centered universe Galileo’s observations. 2. Jupiter’s moons Jupiter has moons! > there are things that do not orbit the Earth!

Sun-centered universe Galileo’s observations. 3. Phases of Venus Venus has phases, just like the Moon Attributed them to Venus’ motion around the Sun

Sun-centered universe Galileo’s observations 1. Moon not a “perfect celestial object” 2. Jupiter has moons that orbit around it and not around the Sun 3. Venus has phases as a result of its orbit around the Sun. This observational evidence convinced Galileo of the validity of Copernicus’ theory. Father of scientific method spin-offs: Jupiter’s moons as a universal clock. E.g., used by Lewis & Clarke for longitude measurements! Stimulated Newton towards universal theory of gravity Father of scientific method spin-offs: Jupiter’s moons as a universal clock. E.g., used by Lewis & Clarke for longitude measurements! Stimulated Newton towards universal theory of gravity

Copernicus is right! Earth is not at the centre!

Hot questions of recent time how do stars work? how are chemical elements made? how big is the universe? what are “spiral nebulae”? what are quasars? are there planets around other stars?...

Better tools got us the answers

Hot questions of today and tomorrow 1. how do planets form? 2. how do stars form? 3. how do galaxies form? 4. what were the first objects to form after the Big Bang?

To address these questions, we need great tools

What makes a great tool?

Three things that count 1. sharpness of image resolve structure - get into the details 2. wavelength coverage go after different physical processes in the same object 3. ability to collect lots of light go after faint objects lots of detail on brighter objects

from the groundfrom space

1. sharpness of image resolve structure - get into the details 2. wavelength coverage go after different physical processes in the same object 3. ability to collect lots of light go after faint objects lots of detail on brighter objects Three things that count

M31 CO and optical

M81: starlight & dust

1. sharpness of image resolve structure - get into the details 2. wavelength coverage go after different physical processes in the same object 3. ability to collect lots of light go after faint objects lots of detail on brighter objects Three things that count

Bigger is better 10m diameter 5mm diameter

The eye vs Keck eye Keck advantage photons/sec entering “instrument” : π(5/2 mm) 2 π(10/2 m) 2 4,000,000 x of these, actually detected: ~1% ~90% 90 x persistence (Integration time): 1 hr 3600 x bottom line: ~1.3x10 12 x

How do we go about it? 1. size 2. location, location location

Bigger is better 10m diameter 5mm diameter

How do we go about it? 1. size 2. location, location location

Location, location, location important for sharpness of image clarity of atmoshpere (“seeing”) or no atmosphere at all ability to detect different wavelengths Earth’s atmosphere absorbs light (esp. bad at IR) so... get above the atmoshpere

from the groundfrom space

Hot questions of today and tomorrow 1. how do planets form? 2. how do stars form? 3. how do galaxies form? 4. when did the first structures (galaxies, stars...) form in the universe?

The future (A Canadian perspective)

ALMA (2010) JWST (2014) TMT (2018 ? ) Three world-class telescopes for Canada

ALMA (Atacama Large Millimetre Array) radio interferometer consisting of 64 12m antennas

ALMA (Atacama Large Millimetre Array) at 5000m elevation in the Atacama desert (Chile) location minimizes water vapour in the atmosphere

ALMA (Atacama Large Millimetre Array) Capabilities: star formation in the early Universe: heat emission from dust in distant galaxies molecular (cold) gas in distant galaxies very high spatial resolution = study internal structures large collecting area = high sensitivity

JWST (James Webb Space Telescope) Next generation space telescope (successor to Hubble) with a 6.5m segmented mirror

2.8m diameter6.5m (equivalent) diameter

JWST (James Webb Space Telescope) Capabilities: infrared (heat) observations from space very high spatial resolution: study structural details of distant galaxies search for planets around other stars large collecting area = very sensitive

TMT (Thirty Meter Telescope) Extremely large optical telescope with adaptive optics

30-m diameter (duh!) 3x bigger diameter than Keck => 9 times more collecting area Capabilities: huge mirror: extreme light-gathering power adaptive optics: resolve very fine details or small separations extremely complementary to JWST TMT (Thirty Meter Telescope)

ALMA (2010) JWST (2014) TMT (2018 ? ) Three world-class telescopes for Canada