Ways of viewing the universe

Planets do not twinkle because they are closer and not a single point of light.

Because stars produce different kinds of energy, we want to study all of them - not just visible light!! Our eyes receive only a very small part of that energy!

We only see the visible range. But stars give off energy in all the wavelengths!

Optical telescopes - Using light to discover information about the universe. There are two kinds:

Uses lens to collect the light. Refracting

Two of Galileo's refracting scopes.

Today’s refracting telescopes!

Uses mirrors to collect light Reflecting scope Reflecting telescope

Newton's reflecting scope

Spotting scope - A small refractor to line up the big scope. Eyepiece for viewing Today’s refractor

Mount Palomar Observatory Hale Telescope Inside Mt. Palomar Observatory Large telescopes are put in observatories to protect them.

Other scopes at Palomar Look across the mountain tops!

Where should we put our telescopes? 1. Mountain tops above atmospheric haze. Reduces the twinkle effect and distortion. 2. Far from city lights ( light pollution). 3. If our atmosphere blocks the wavelength needed to study, then the scope goes into orbit!

Notice which wavelengths are blocked!

The USA at night – notice the light pollution. Where would you put a telescope? Atlanta Notice the Great Lakes

Mauna Kea, Hawaii – elevation 13,796 ft High to “look through” less atmosphere

Multi-mirror reflector in Hawaii

Other scopes are studying all the other wavelengths.

Infrared scope in Hawaii Infrared scopes “look for” heat and are best at locating new stars just forming.

COBE - An Infrared scope that is in orbit. Cosmic Background Explorer It has located very important data about the formation of the universe. Infrared = heat

The constellation of Orion in visible light energy and infrared energy. These two views see very different things in the same area of the sky!

Radio Telescopes Records radio waves Sees to the edges of the universe

VLA New Mexico Very Large Array uses multiple radio telescopes.

VLA from above. They work as a unit kind of like a fly’s eye.

Largest radio scope in the world in the top of an extinct volcano! Puerto Rico

Ultraviolet telescopes Records UV radiation. Astronomers use this wave length mostly to look at and track what the sun is doing.

Solar & Heliospheric Observatory This spacecraft has an ultraviolet scope.

SOHO pictures The sun in different UV wavelengths.

X-ray telescopes Records x ray emissions from objects in “deep” space Best for “looking” for black holes, dying stars, and other strange objects. Must be above the atmosphere!

Chandra X-Ray scope

X Rays from two Black holes in one Galaxy.

Gamma Rays These telescopes are looking for high energy events: black holes, neutron stars and quasars. Due to their high energy content, Gamma rays are able to cause serious damage when absorbed by living cells. Gamma rays are also able to penetrate dense materials. Aren’t we glad our atmosphere blocks them!

The Compton Gamma Ray Observatory orbits the Earth, detecting high-energy photons – GAMMA RAYS

The spectroscope Takes light from stars and analyzes it.

Light from a star or other source goes through the slit.

Every element has a different set of spectrum lines. Much like people having different fingerprints.

Krypton’s spectrum Neon’s spectrum Emission spectrum

Three kinds of spectra

So spectrum lines tell use what elements are in a star without going there!

Notice that emission and absorption are the same.

Any questions on how we view and study the universe??