Unit 2 & 3 Flashcards
Describe the enormous amounts of time it takes spacecraft to travel long distances
Fastest spacecraft travels 58,000 km/h. At this speed, it would take 75,000 years to reach to nearest star
What is a light year?
A measure of distance
What is luminosity?
The actual brightness of a star
What is apparent magnitude?
The brightness of stars as they appear
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Brightest Dimmest
What is absolute magnitude?
How bright a star really is. (Stars are aligned at the same distance)
How does the color help determine the temperature of a star?
Stars with cool surfaces are red, while stars with hot surfaces are blue-white
What is geocentric?
Earth centered
What is heliocentric?
Sun centered
What were the contributions from Kepler, Galileo, and Copernicus?
Kepler - Laws of Planetary Motion
Galileo - Used a telescope
Copernicus - Heliocentric model
What is gravity?
Force of attraction between two objects due to their masses
What does Keplers 1st law state?
Planets orbit in an elliptical path
What does Keplers 3rd law state?
The farther away someone is from the sun, the longer its orbit is
What is Newtons law of universal gravitation?
Gravitational force ^ as the mass of the objects ^
Gravitational force decreases the farther the objects are
(Inverse relationship)
What are the layers of the sun in order?
The core, the radiative zone, the convective zone, the photosphere, the chromosphere, and the corona
How does the sun produce energy?
By nuclear fusion
What is nuclear fusion?
Two low-mass atomic nuclei fuse to form another, heavier nucleus, and matter is converted into energy
What is convection?
Movement of matter due to differences in density
Where does convection happen?
The convection zone
What is differential rotation?
Different parts of the body route at different speeds (the sun’s equator rotates faster than the poles)
What is a sunspot?
A dark area on the photosphere that is cooler
What is a solar flare?
Explosive release of energy
What is a prominence?
A huge loop of gas
What are terrestrial planets and what are a few properties of them?
A planet that is highly dense, and composed of rock and metal. They rotate slowly, and have no rings and few satellites
Wy is Pluto classified as a dwarf planet?
Because it doesn’t have enough mass to clear the junk out of its orbit
