Astronomy Flashcards
define asteroids
small celestial objects in the solar system composed of rock and metal that orbits the sun
define comets
large chunks of ice, dust and rock that orbit the sun
define meteoroids
piece of metal or rock in the solar system that is smaller than an asteroid
define meteors
meteors are streaks of light/space rocks that crash through earth’s atmosphere
define meteorites
a meteor that survives its passage through the earth’s atmosphere
define planets and dwarf planets
planets dominate there orbit where as dwarf planets do not
what’s the difference between terrestrial planets and gas giant planets
terrestrial are closer to the sun and made up of a rocky shape where as gas giants are furthest from the sun and are made up of gasses and liquids
describe the organization of our solar system. what does heliocentric mean?
our solar system has 7 planets that revolve around our sun. heliocentric describes how the sun stays stationary while the planets revolve around it
Define and provide examples of satellites
A satellite is a body (either natural or man made) that orbits around another body in space. for example the moon is a satellite
What is earth’s orbit?
The path an object follows as it moves around another object
What is Earth’s orbital period?
One complete orbit is 365.256 days
What is Earth’s rotation?
Rotation of planet earth around it’s own axis
What is Earth’s revolution?
The revolving of the earth around the sun, producing the number of days in the year
How many phases of the moon are there
There are 8
What are the phases of the moon (in order)
- New moon
- Waxing crescent
- first quarter
- waxing gibbous
- full moon
- waning gobbous
- Third quarter
- waning crescent
Describe the phases of the moon
The amount of sunlight shining on the moon at different times of the month
Describe Astronomical phenomena (including seasons, eclipses, and tides)
Astronomical phenomena happens because of the motions of the earth, moon, planets, and satellites
What is a light year?
A light year is the distance that light travels in a year
What is the formula to convert light years to KM, and KM to light years
1ly = 9.46 x 10(to the power of 12)km
How many KM in one light year
9,460,528,405,000KM
What are the characteristics of stars and what do their colours mean?
Characteristics:
- Self luminous (radiate light and heat energy)
- Stars rotate about their own galaxy
- Stars rotate about the center of a galaxy
The colors of a star indicates the temperature
What is red shift
The phenomenon of light from galaxies shifting toward the red end of the visible spectrum, indicating the galaxies are moving away from earth.
What is an astronomical unit
The average distance between the earth and the sun.
It can be used to measure distances within our solar system
Convert astronomical units to km and km to astronomical units
1 AU = 150 000 000 km
How many km in 1 astronomical unit
150 000 000 KM
What are the characteristics of the sun and what are its elements
- 75% hydrogen & 25% helium
- Core temp is 15 million K
- Pressure is 200 billion times earth’s surface pressure
What important reaction happens at the sun’s core
Nuclear fusion
What is the H-R Diagram? What information can we get about stars from it?
It shows the relationship between a stars temperature and its luminosity
Define luminosity
Total amount of energy produced by a star each second
What is the solar nebula theory? What is the big bang theory
Solar nebula theory: is the theory on the formation of our solar system from a nebula cloud from a collection of dust and gas.
Big bang theory: The theory that the universe began in an incredibly hot, dense expansion approx 13.7 billion years ago.
