Planetary Motion

When a planet is at perihelion it is ____.

• Closest to the sun in its orbit.

• Farthest from the sun in its orbit.

Tags

NGSS.MS-PS2-4

When a planet is at perihelion it is ___.

• closest to the sun in its orbit

• farthest from the sun in its orbit

Tags

NGSS.MS-ESS1-2

Ptolemy used epicycles to explain the motions of the sun, moon, and planets in his ____ model of the solar system. that had everything orbiting Earth.

• heliocentric

• geocentric

• orrery

Answer explanation

According to Kepler's 1st Law, planets orbit the sun in _____ orbits.

• circular

• oval

• elliptical

• epicycle

Answer explanation

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

Earth has a variety of motions. It orbits the sun, with a period of 1 year. It rotates on it's axis once a day. It also "wobbles" on its axis over a period of 26,000 years. Currently our north pole points at Polaris. In the distant past, it pointed at Thuban, in the constellation Draco. This "wobble" is called _____.

• nutation

• precession

• retrograde motion

When does the Earth have the highest speed - when close to the sun, or when far from the sun?

• close to

• far from

Tags

NGSS.MS-ESS1-2

Which planet has an orbit with the lowest eccentricity?

• Mercury

• Venus

• Earth

• Mars

In orbits with low eccentricity ___.

• The foci are far apart

• The foci are close together

Calculate the eccentricity for the following orbit. 

• 6

• 0.8

• 0.6

• 1.2

Tags

NGSS.HS-ESS1-4

Which object would have an eccentricity closest to 0?

• Red

• Green

• Blue

• Yellow

• Pink