SP5a Astronomy Flashcards
Star?
huge ball of gas that radiates energy.
Planet?
large body in space that orbits a star.
Dwarf planet?
body orbiting the sun that is too small to be classed as a planet.
Asteroid?
a small lump of rock orbiting the sun.
Comet?
a small lump of dirty ice orbiting the sun.
Moon?
natural satelite orbiting a planet.
Recall the eight plaents in the solar system from the one closest to the sun to furthest.
mercury - venus - earth - mars - jupiter - saturn - uranus - neptune
Who founded the geocentric model?
Claudius Ptolemy (in 150AD)
What does the geocentric model indicate?
that planets move in small circles as they orbit the earth.
Who founded the heliocentric model?
Nicolaus Copernicus
What does the heliocentric model indicate?
that planets orbit the sun and not earth. This model excluded uranus and neptune.
Who improved the heliocentric model and how?
Johannes Kepler, by observing that the orbits of the planets were ellipses.
How have telecopes been developed?
they have been developed to detect diffeent wavelengths of the electromagnetic spectrum.
Why are some telecopes located outside our atmosphere?
to detect electromagnetic wavelengths, such as infra-red, which are absprbed by the atmosphere.
Willaim Herschel built a reflecting telescope which could do what?
gather more light than most refractors. They had bigger apertures.