Distances in Space

How are objects located on the celestial sphere?

• longitude and latitude

• declination and parallax

• declination and right ascension

• left ascension and right ascension

What is a constellation?

• a pattern of stars visible in the night sky

• a region of the sky described by the celestial sphere

• both A and B

• neither A nor B

What is parallax?

• the average distance between a celestial object and Earth

• the angle formed by Earth and two celestial bodies located in different directions from Earth

• the apparent difference in the position of an object when viewed at the same time each year

• the apparent difference in the position of an object when viewed from different lines of sight

How do scientists define an astronomical unit?

• the distance between Earth and the moon

• the distance between Earth and the sun

• the distance from one end of the solar system to the other

• the distance from one end of the Milky Way galaxy to the other

Tags

NGSS.MS-ESS1-3

What is necessary to calculate a star's distance from Earth?

• the parallax angle

• the position of the star observed twice, six months apart

• the distance between the two points of observation

• You need all of these.

A light-year is a measure of

• time.

• distance.

• speed.

• velocity.

How do light-years help astronomers to determine the ages of distant objects in space?

• To calculate an object's distance from Earth in light-years, astronomers must first know the object's age in years.

• Light in space travels approximately 9.5 trillion km per year. Therefore, the images that astronomers see of distant objects actually show what those objects looked like long ago.

• Light in space travels approximately 9.5 trillion km per year. Therefore, an object's distance from Earth in light-years is equivalent to the object's age in years.

• To calculate an object's distance from Earth in light-years, astronomers must first know the object's age in years.

How does this image demonstrate parallax?

• The same viewer is viewing the same car at two different times of year.

• Two different observers are viewing two different cars under very similar circumstances.

• The position of the car appears to change when viewed through two different perspectives.

• The same viewer is viewing the same car at two different distances from the car.

A star is located approximately 500 million light-years from Earth. Can a student determine the star's distance by calculating its parallax angle?

• No. Parallax cannot be used to calculate the distances of objects more than approximately 300 light-years away.

• Yes. Parallax enables astronomers to calculate the distances of objects fewer than 1 billion light-years away.

• The student cannot use the parallax angle alone to determine the star's distance; the student must also know the star's age.

• The student cannot use the parallax angle alone to determine the star's distance; the student must also know the star's size.

What is the distance of an object from Earth if the object is 8 AU from the sun? (Assume that both Earth and the object are located in the same direction from the sun.)

• 5 AU

• 6 AU

• 7 AU

• 8 AU

Tags

NGSS.MS-ESS1-3