Astro_CH2_modeling

Stars move slowly across the sky from the ________ to the _________ throughout the night.

• East , West

• Wast , East

• South , North

• Nouth , Sorth

a planet sometimes moves westwards for a few months.

Such westward motion of a planet is called (a)   motion.

What is the typical duration of retrograde motion?

• A few hours

• A few days

• A few months

• A few years

When observed from the Earth, which of the following planets appear(s) only either near the western horizon just after sunset or near the eastern horizon just before sunrise?

  (You can choose more than one answer.)

•   A  Mercury

•   B  Jupiter

•   C  Venus

•   D  Mars

Match the following

• The geocentric model

• The heliocentric model

• The Copernican model

• Expansion of the Universe

• Hubble's Law

• The Ptolemaic model

The Ptolemaic model

b

a

epicycle

defernt

In the Ptolemaic model​, The centres of the epicycles of Mercury and Venus were assumed...

• to lie on a straight line connecting the Sun and the Earth.

• Orbits the earth with same linear speed

• Orbits its own epicycle with same angular speed

Answer explanation

The Copernican model heliocentric model, Which planet moves faster, and so retrograde motion occurs

• Mars

• Earth

In Copernican model, Which of the following situation can retrograde motion occur.

• on earth observe mars

• on mars observe earth

• on Neptune observe earth

• on earth observe Neptune

In Copernican model, Which of the following situation can morning star occur.

• on earth observe mars

• on mars observe earth

• on Neptune observe earth

• on earth observe Neptune