ASTR-1010 Planetary Astronomy Day - 19

Announcements Smartworks Chapters 4: Due Monday, March 1. Smartworks Chapter 5 is also posted Exam 2 will cover chapters 3, 4, & 5 -Target Wednesday, March 3 ***Bring your Lecture-Tutorial books to the exam. They will be collected and graded. - Make SURE your name is in it!

Once a site with good “seeing” is found everyone wants to use it Kitt Peak, AZ

Mauna Kea Hawaii

Today most observations are done with a CCD Camera

CCD’s are much more sensitive than photographic film

ClassAction Stuff CCD Simulator Splash page questions

If you pass white light through a prism, it separates into its component colors. long wavelengths ROY G B I V short wavelengths spectrum

Another common measuring device is the spectrograph

The best spectrographs use diffraction gratings

The spectrograph/CCD produces a black & white spectrum

Spectra can be displayed as a graph or rainbow of color

Multitasking Saves Time

But visible light is only one type of electromagnetic radiation (light) emitted by stars Astronomers are truly interested in the entire spectrum of Light!

Consider This Class as Seen in Different Wavelengths of Light!

Consider Orion as Seen in Different Wavelengths of Light!

Observations at other wavelengths are revealing previously invisible sights UV infrared Map of Orion region Ordinary visible

Radio wavelength observations are possible from Earth’s surface

Observing In Radiowaves Long Wavelength…poor resolution

Under the dish at Arecibo

The Very Large Array (VLA)

Saturn In Different Wavelengths Near IR Visible Radio

Astronomers use different instruments to look at light of different wavelengths - sometimes, we even have to go above Earth’s atmosphere.

Not all EM radiation can penetrate Earth’s atmosphere.

Atmospheric Windows

Telescopes and Earth’s Atmosphere Lecture Tutorial pg. 49 Work with a partner! Read the instructions and questions carefully. Discuss the concepts and your answers with one another. Take time to understand it now!!!! Come to a consensus answer you both agree on and write complete thoughts into your LT. If you get stuck or are not sure of your answer, ask another group.

Which is the correct reasoning for why a gamma ray telescope located in Antarctica that is to be used to look for evidence of black holes in the centers of galaxies would not get funded? There is no way to detect the presence of a black hole. Gamma rays are too energetic to detect with a telescope. You can’t build a functioning telescope in Antarctica. Gamma rays don’t penetrate Earth’s atmosphere.

Imagine you’re the head of a funding agency that can afford to build only one telescope. Which of the four proposed telescopes below would be best to support? A gamma ray telescope in Antarctica A radio telescope in orbit above the Earth A visible telescope located high on a mountain in Peru An ultraviolet telescope located in the Mojave desert