P3.3.2 Detecting Alien Life Flashcards
How can scientists estimate if there are Earth-like planets out there that can support life?
They use mathematical models.
Who created the Drake equation, which predicts how many planets are likely to have life on them?
Frank Drake
What does SETI stand for?
Search for Extra-Terrestrial Intelligence
How does SETI work?
Using radio telescopes which detect radio signals from space.
Which types of electromagnetic radiation can reach the Earth’s surface?
Most radio waves, visible light and some infrared and ultraviolet radiation.
What happens to the other types of electromagnetic radiation?
The rest are absorbed by the atmosphere.
What essential features do you need for Earth-like life?
Energy source, liquid water and oxygen
How can astronomers work out what stars are made of?
By looking at the light that they emit. They produce a line spectrum
What do the black lines on a line spectrum mean?
They show which elements are present in the gas the light has travelled through. We can compare this to gases we already know the spectra for.