P1.3 Flashcards
Moon diameter (KM)
3 500
Earths diameter?(KM)
13 000
Sun diameter (KM)
1 400 000
Neptune diameter (KM)
50 000
Milky Way diameter (KM)
1.0 x 10^18
Andromeda diameter (KM)
1.4 x 10^18
Moon distance from Earth
384,000km
Sun distance from Earth
150,000,000 km
Neptune distance from Earth
4,500,000,000km
Andromeda distance from Earth
2.5 x 10^14
What methods are used to investigate the existence of alien life
Space probes
Soil experiments by landers
SETI (search for extraterrestrial intelligence) ; analyse radio waves from space .
what is the steady state theory and what evidence is there to support it
The universe has always existed and is expanding. New matter is continuously created as the universe expands
Red shift
What is observed when a wave source is moving away?
Red shift (Longer wave length, shorter frequency)
What is the solar system part of
The Milky Way Galaxy
What is a Galaxy
A collection of stars
Why are some telescopes located outside the Earths atmosphere ?
Because light waves are not reflected by clouds/dust
The atmosphere gets in the way as it absorbs a lot of light coming from space before it can reach us.
What do planets reflect?
Planets reflect sunlight
What do all planets orbit around
Stars
What is the smallest planet
Mercury
What are the dark lines called in a spectrometer?
Absorption spectra.
What’s causes an absorption spectra?
They are caused by light at those wavelengths being absorbed e.g. By elements in the star’s atmosphere
What are the bright lines in a spectrometer?
Emission spectra
What causes emission spectra
Emission spectra is caused by extra light being emitted at those wavelengths
What provides proof that the universe is expanding?
Red shift
Which is the only theory that provides an explanation for CMB radiation?
Big Bang
