16-6: How Do Astronomers Measure Distance?
nearby stars have what of a parallax than a distant star do?
a larger angle of parallax
what is the average distance from earth to the sun?
about 150 million km
what does atronomers call this distance?
an atronomical unit
parallax
apparent change in the position of a distant object when seen from two different places
why did scientist create special units to measure distances in space?
because of the very large numbers they needed to create special units to measure distances in space
why do astronomers not measure the distances to stars in kilometers?
distance to stars are so great that the number are too large to work with easily.
by measuring how much the nearby star appears to move, atronomers can calculate what?
how far away the star actually is.
atronomers often measure the distance to an object in space using what?
light years
atronomers can use what to find out distance to the closer stars?
parallax
most distance on earth can be used measured in?
1. meters 2. kilometers
what is the distance of the planets from the sun?
1.Mercury- 0.4 AU 2.Venus- 0.7 AU 3.Earth- 1.0 AU 4.Mars- 1.5 AU 5.Jupitar- 5.2 AU 6.Saturn- 9.5 AU 7.Uranus- 19.2 AU 8.Neptune- 30.1 AU 9.Pluto- 39.4 AU
a light year is equal to almost how many trillion of km?
10 trillion km
one atronomical unit, or 1 AU, is equal to how many km?
150 million km
light travels through space at a speed of about how many km per second?
300,000
Proxima Centauri is how many km from earth?
40,000,000,000,000
light from the north star, polaris, reaches earth in about how many years?
700 years
light from the sun reaches earth in a little more than how many minutes?
8 minutes
the closest star, other than the sun, to earth is called?
Proxima Centauri
an atronmical unit can also be used to measure what?
the distances in space, especially distances between the planets in the solar system.
astronomical unit (AU)
unit of measurement based on the sun's distance from Earth and equal to about 150 million km
light year
unit of measurement equal to about 10 trillion km
how would you measure the distance from earth to the stars?
using kilometers
