How we See the Universe Mission 2

2 Putting it into perspective When we organize light waves in this type of order, we call it the “Electromagnetic Spectrum” or EMS

3 Wavelength = distance between crests Amplitude = half the height of trough to crest Frequency = number of crests that pass a point in space every second … so wavelength = speed / frequency Do the wave

4 What does the EMS tell us? (Electromagnetic Spectrum) Transports energy Electric and magnetic fields oscillate: that’s the “wave” Moves at speed of light, 3 x 10 8 m/s Wavelength, frequency, energy all related Type of radiation (usually) depends on energy/temperature of object

5 I like a place with a little atmosphere… Only visible, radio and some IR and UV gets through the air! To see gamma rays, X-rays, most UV and some IR you must go to space

Spitzer Infrared Video

Different Views from the Inside

8 Sources  Name some visible sources of light in the room  Is the wall at the front of the room a light source? Definition: Sources of light are objects that emit light energy Flashlight Projector Laptop Monitor But it seems to be emitting light? Oh, I see the wall is reflecting the light, not emitting it.  What is a light source?

9 What is a detector? Detectors Are there any other light detectors that you know of? Those two openings on either side of our noses! Solar Calculators Cameras Can you tell me where there are light detectors in this room?

10 Transmitters and Shields  What are some things that don’t allow light through? Is it safe to say these things “Shield the Light”?  What are some materials we know of that do allow light to either completely or partially pass through it? Is it safe to say these things “Transmit the Light”?

11 Invisible Sources of Light There are 6 different stations throughout the room. They are equipped with a source of invisible light and a detector for detecting that light. In a moment we will break up into groups. Each station will have a set of materials. These materials are potential shields.

12 Procedure Each group will go from station to station. You have about 5 minutes per station. As scientists we are obligated to make a prediction about how we think each material will behave. DO THIS FIRST! Then test each material at each station to see if it is a Transmitter (T) or a Shield (S) for that particular type of light. Try to determine the common properties of the materials that block the different types of light

13 Stations: AM Radio Infrared lamp Flashlight FM Radio Remote control “Black” light Let’s Get Busy!

14 What did we learn?  What property of the materials we tested caused radio waves to be blocked?  Are all the plastics we tested translucent/transparent to infrared light?  If someone had no sunscreen while at the beach what could they cover their face with to keep from getting sun burned by UV light?

15 M45 – The Pleiades Cluster X-ray: T. PreibischUltraviolet: MSXVisible: AAO Infrared: IRASRadio: NVSS

16 Multi-wavelength Crab Nebula X-ray: Chandra Ultraviolet: UIT Visible: Palomar Infrared: 2MASS Radio: VLA

17 M51 – The Whirlpool Galaxy X-ray: ChandraUltraviolet: GALEXVisible: T. & D. Hallas Infrared: ISORadio: VLA