1. Introduction
You are an astronomer who has just made this image. As you study this image, what questions do you ask?
Elicit answers from your audience. Then click on the slide numerous times. Each time a new question will appear.

2. Introduction What are these “fuzzy” objects? What are they made of?
How were they formed?
What are they made of?
How old are they?
Are they moving?
How far away are they?
Are they part of a system?

3. Neon
Sodium
Hydrogen

4. Radio Spectral Line
Hydrogen
NGC 628

5. 40 Foot Telescope
Front end
Forty Feet
Control room

6. Frequency x wavelength = c c = 300 million meters/sec 1Megahertz = 1 million waves/sec. Radio station=100 megahertz What is the wavelength of the signal?

7. Range of frequencies = bandpass, bandwidth

8. 40 Foot Receiver bandpass: 1370-1440 MHz What is the wavelength of 1420 MHz?

9. RA and Dec = Long. And Lat.

11. Galactic Long. And Lat. 11