1. GCSE Science A Physics 1 Space Learning Outcomes Appreciate the range of distance scales appropriate when discussing the universe. Know that atoms of a gas absorb light at specific wavelengths which are characteristic of the elements in the gas. Know that scientists in the nineteenth century were able to reveal the chemical composition of stars by studying the absorption lines in their spectra. Appreciate the range of distance scales appropriate when discussing the universe. Know that atoms of a gas absorb light at specific wavelengths which are characteristic of the elements in the gas. Know that scientists in the nineteenth century were able to reveal the chemical composition of stars by studying the absorption lines in their spectra.

2. GCSE Science A Physics 1 Space Key Words: Galaxy: A collection of stars Universe: The collective name for all the galaxies Spectroscopy: A way of working out what elements something is made of by looking at the frequencies of light it absorbs/reflects. Galaxy: A collection of stars Universe: The collective name for all the galaxies Spectroscopy: A way of working out what elements something is made of by looking at the frequencies of light it absorbs/reflects.

3. GCSE Science A Physics 1 Space

4. GCSE Science A Physics 1 Space Relative distances! 40,700,000,000,000km - Sun to nearest star 384,000 km - Distance between Earth and Moon 225, 000, 000 km - Earth and Mars 150, 000, 000km -Sun and Earth 18,900,000,000,000,000,000km - Milky way to nearest galaxy 40,700,000,000,000km - Sun to nearest star 384,000 km - Distance between Earth and Moon 225, 000, 000 km - Earth and Mars 150, 000, 000km -Sun and Earth 18,900,000,000,000,000,000km - Milky way to nearest galaxy If they are so far away, how do we know so much about them?

5. GCSE Science A Physics 1 Space

6. GCSE Science A Physics 1 Space Spectra Sodium absorption spectra Sodium emission spectra

7. GCSE Science A Physics 1 Space

8. GCSE Science A Physics 1 Space

9. GCSE Science A Physics 1 Space A spectrometer is a tool used to analyse light given out by stars and galaxies. It works very simply by the Telescope directing a beam of light into the spectromenter and through a slit, This diffracts the Light and splits it up into, a spectrum – simular to a prisum. The light spectra from stars contain dark lines theese dark lines are causd by the light at those wavelengths being absorbed by elements in the stars atmusphere. These patters of dark lines are called absorption spectra. Absorption spectra can be used to work out what the stars and galaxys are made of – each element has its own particular absorption spectrum. The spectra for galaxies further away apear more red than they should.