Section 3.1 Using Technology to see the Visible  With just your eyes, looking into space is just a bunch of dots in the sky.  When we add technology to our eyes we can see further into our galaxy  Different telescopes allow us to see different things in the sky and the world that surrounds us!

Optical Telescopes  Have been used for over 400 years  1608 – First telescope made by Hans Lippershey,but Galileo is credited with first using a telescope to see the night sky  Bigger telescopes enable astronomers to discover new bodies in space.  Sir William Herschel built a huge reflecting telescope and discovered the planet Uranus with it in 1773.

Refracting Telescopes  Uses 2 lenses to gather and focus the light  Limited because the glass can not be more that 1m wide  Think of looking through a glass pop bottle and trying to see images!

Reflecting Telescopes  Use mirrors instead of lenses to gather and focus the light from the stars  Contains a large concave mirror coated with a thin layer of metal (usually aluminum)  Polished to a shiny finish to reflect the faintest of light it receives  One of the larges lenses is 6m wide

Keck Telescopes

Combining Telescopes  The technique of using a number of telescopes in combination is called interferometry.  When working together, these telescopes can detect objects in space with better clarity and at greater distances than any current Earth-based observatory  Keck I and II are a great example of this – together they can detect objects with great clarity in space

The Hubble Telescope  Remote mountains make excellent sites for telescopes BUT light and air pollution along with clouds, humidity and even high winds can interfere with star gazing.  The Hubble Space Telescope, launched in 1990, offers a solution to these problems.  Orbiting 600 km above the Earth, the reflecting telescope is 14 m in length and 4.3 m in diameter  In May of 2009, a 13 day revamp took place of the Hubble Telescope; this being the last of 5 trips to service the telescope  They swapped out old gyroscopes and batteries with new ones and performed two intricate repairs to revive advanced cameras and versatile imaging technology

IMAGES FROM HUBBLEIMAGES FROM HUBBLE

 Hubble Video – Revelations Hubble Video – Revelations