TELESCOPES

How do they work?

There are two types of Telescopes

Refractor telescopes They use glass lenses

Reflector telescopes

They use mirrors and lenses

Parts of a Telescope

Tube - a long tube, made of metal, plastic, or wood

Objective Lens (in refractors) or Primary Mirror (in reflector) - collects lots of light from a distant object and concentrates it to a point or focus.

Eyepiece - takes the bright light from the focus of the objective lens or primary mirror and "spreads it out" (magnifies it) to take up a large portion of the retina.

More Telescope Parts…

1. Finderscope 2. Focuser 3. Eyepiece 4. Release Control For Mount 5. Mount Base or Mounting Plate 6. Outer Tripod Leg 7. Tripod Leg Extension 8. Tripod Support Brace 9. Accessory Tray 10. Tripod Leg Clamp 11. Mount Axis 12. Mount 13.Mirror Cell – Primary 14. Telescope Tube 15. Slow Motion Control Lock 16. Finderscope Eyepiece 17. Finderscope Bracket

Why can’t you see an object that is far away? The object does not take up much space on your

eye’s screen - retina.

How does this apply to telescopes?

If you had a bigger eye, you could collect more light from the object. This image could be magnified so it stretches out over more pixels in your retina.

Eyepiece

produce and allow you to change the telescope's magnification

determine the telescope's field of view:

how much of the sky is seen edge-to-edge through the eyepiece alone

Reflecting telescopes focus light by bending them with mirrors

Refractor telescopes use a big lens to gather the light and direct it to a focal point and a small lens to brings the image to your eye.

A telescope has two properties

Aperture - how much light can be collected

The larger the lens or the mirror, the more light the telescope collects and brings to focus, and the brighter the final image will be.

Magnification - how much the eyepiece

can enlarge the image

What can we see with a Telescope

Total Lunar Eclipse, December 21 2010

SPACE EXPLORATION

Why Do We Explore Space?

Space exploration is important because it helps people to better understand the world in which they live. It enables people to gain knowledge about the origins of the solar system and formation of natural resources.

Space exploration also provides an opportunity to make advancements is science and technology.

INTERNATIONAL SPACE STATION

the station orbits the Earth once every 90 minutes The space station provides a microgravity environment for researchers to conduct multidisciplinary investigations, for educators to inspire next generation scientists and engineers, and to serve as a stepping stone to future exploration that was not possible just 15 years ago.

Hubble floating above Earth

The Hubble Space Telescope has had a major impact in every area of astronomy, from the solar system to objects at the edge of the universe.

Not everything is visible…

Many modern day telescopes do not use visible light to collect images.

Radio telescopes, x-ray telescopes and infrared (IR) telescopes have become a staple of modern day astronomy, producing some amazing images.

www.yorku.ca/eye/spectrum.gif

Very Large Array (VLA) radio telescopes

Most Powerful Radio-Telescope in the World

Location - Atacama desert in Chile - altitude of 5,000 meters

Observation field - millimeter/submillimeter-wavelength

Time to design and build – more than 10 years

Project funded by - Canada, Chile, the European Union, Japan, Taiwan and the United States ALMA TELESCOPE IN CHILE – VIDEO

ALMA Telescope

La-Silla Observatory Chile

The James WEBB Space Telescope

JWST will be a powerful time machine with infrared vision that will

peer back over 13.5 billion years to see the first stars and galaxies

forming out of the darkness of the early universe.

Meteorites

The biggest chunk of the Chelyabinsk meteorite crashed through the ice of Lake Chebarkul on Feb. 15, after the meteor exploded in the Earth's atmosphere, breaking windows and injuring more than 1,000 people.

NASA had looked only for space rocks about 30 metres wide and bigger, figuring there was little danger below that.

The crater left…

The Chelyabinsk meteorite was thought to be 20 meters in diameter and 11,000 tones when it streaked through the sky over Russia, making it the largest object to hit Earth since 1908.

Resources

Hubble

http://www.youtube.com/watch?v=qGNgrMNklrc

ISA - Spot the station

http://spotthestation.nasa.gov/

ISA presentation

http://www.youtube.com/watch?v=tXhUbR2UAyQ

James Web Space Telescope

http://www.youtube.com/watch?v=k2wtBWYjdRk