The sun is massive. It contains 99.8% of the mass in the solar system and is made up of several different elements. Which of these elements makes up about 25% of the mass of the sun?

Helium

What is Newton’s law of universal gravitation?

Gravitational force increases as the mass of an object increases or as the distance between two objects decreases.

The terrestrial planets include Mars, Venus, Earth, and which other planet?

How are Jupiter and Saturn similar?

They have many satellites.

Which term describes a bright streak of light that results when a meteoroid burns up in Earth’s atmosphere?

Centripetal force is a force that makes a body follow a curved path.    

The Kuiper Belt is being constantly studied. To date, about how many objects have been found in the Kuiper Belt?

What is the primary atomic reaction that takes place within the sun and converts hydrogen atoms into helium atoms?

Much of the surface of Mars is dry and dusty.  What weather conditions do winds on Mars most likely create on Mars?

The table below shows some information about the period of revolution of Earth and the gas giant planets.

How long does it take Neptune to complete two full revolutions in Earth years?

Which stage in the formation of the solar system came first?

Pluto is mainly composed of which materials?

The diagram below shows positions from which Sanjay could be viewing a star. The star appears to be in the gray square.

[image]

From which position is Sanjay observing the star?

During the sunspot cycle, the number of sunspots rises and falls, and their locations change. What is the length of the sunspot cycle?    

Mercury is heavily cratered from meteorite impacts. What difference between Earth and Mercury allows Mercury to be more affected by meteorite strikes?

Large

Lower Densities

Hydrogen and Helium

Rocky Cores with Deep Atmosph.

Far from sun

Planetary Rings and Many Moons

The sun is a low-mass star on the outer reaches of the Milky Way galaxy. Much like Earth, the sun has many different layers that define its structure. Identify the sun’s six layers.

Describe a comet, and indicate where comets are located. Explain why a comet develops a tail when it nears the sun.

A comet is a small body of ice, rock, and cosmic dust that follows and orbit around the sun.  

The comet's tail forms when heat from the sun causes ice in the nucleus to vaporize releasing gas and dust.

Compare and contrast the heliocentric and geocentric models of the Solar System.

Heliocentric Model- Sun Centered

Geocentric Model- Earth Centered

Scientists once classified Pluto as a planet. Then they reclassified it as a dwarf planet. Explain why Pluto was reclassified.