2 points!

Yep! They estimate 5-7 billion years, which is a fairly big gap!

The Sun is a huge mass of hot, glowing gas. The strong gravitational pull of the Sun holds Earth and the other planets in the solar system in orbit. The Sun’s light and heat influence all of the objects in the solar system and allow life to exist on Earth.

For humans, the Sun is beautiful and useful, but also powerful and dangerous. As Earth turns, the Sun rises over the eastern horizon in the morning, passes across the sky during the day, and sets in the west in the evening. This movement of the Sun across the sky marks the passage of time during the day. The Sun’s movement can produce spectacular sunrises and sunsets under the right atmospheric conditions. At night, reflected sunlight makes the Moon and planets bright in the night sky.

The Sun provides Earth with vast amounts of energy every day. The oceans and seas store this energy and help keep the temperature of Earth at a level that allows a wide variety of life to exist. Plants use the Sun’s energy to make food, and plants provide food for other organisms. The Sun’s energy also creates wind in Earth’s atmosphere. This wind can be harnessed and used to produce power.

While it lights our day and provides energy for life, sunlight can also be harmful to people.

What type of light emitted from the sun is particularly harmful to humans?

Lita raises her hand uncertainly. "Ultra-violet?"

Anelreas raised her hand. "Ultra-Violet rays?"

Julia raises her hand slowly and says unsurely "Ultra Violet Rays?"

That's right, 2 points!

So while the sun keeps us alive and sustains life, it can also be harmful too.

The Sun influences Earth with more than just light. Particles flowing from the Sun can disrupt Earth’s magnetic field, and these disruptions can interfere with electronic communications. These are sometimes known as solar flares.

So, radius of the sun?

Anelreas raised her head. " The radius of the sun is 695, 500 kilometers."

Julia thinks for a moment then raises her hand. "The sun's radius is 109 times larger then the earth's radius?"

Rosa raised her hand. 'The mass of the sun is more than 99,8% of the mass of the solarsystem it is 332.946 times the earthmass. in kgs the mass is 1.96E30 kg'

ooc: the E is exp, that's one of the buttons on the calculator (duh) I have no idea how to write it different

^ooc: the E stands for "10 to the power of" (that way it's quicker to type in). So that means that your answer would be 1.96 X 10 to the 30th power.

"I have that the sun's mass is 1.989 × 10 to the 27th power in metric tons," Kali answered, "That's large enough to fit a million Earths inside of it... or am I confusing mass and volume with that last piece?"


Then adding to Rosa's answer she responded, "It takes up 99% of the solar system because it's so massive and the solar system is full of empty space. That means that all the planets, their moons, and all the comet, asteroids, and meteorites and add their masses together, they still wouldn't be as massive as the sun."

Francis smiled as the question had already been answered. She takes notes and waits for the next question.

*Caroline scribbles down notes on a piece of parchment*

Mithos was very happy that Julia earned Ravenclaw house points.

:: Ganymede rolled her eyes and flipped her dark purple hair. She wondered if she could find a way to help Slytherin earn some more points. ::

Julia gives a sigh and copies down some notes. She looks at Mithos and smiles. She looks at her parchment then waits for the next question.

Anila nodded to the Slytherin that answered...hopefully she raked up some points. Anila wondered if she'd ever get the chance to answer...

Thats right! 5 points!

Despite its large mass, the Sun has a lower density, or mass per unit volume, than Earth. The Sun’s average density is only 1.409 g/cu cm (1.188 oz/cu in), which is a quarter of the average density of Earth. The Sun produces an enormous amount of light. It generates 3.83 × 1026 watts of power in the form of light. In comparison, an incandescent lamp emits 60 to 100 watts of power. The temperature of the outer, visible part of the Sun is 5510° C (9950° F).

What is the average distance of the earth from the sun?

Mithos raised his hand "The distance from the Earth to the Sun averages about 93 million miles. It varies about 2% over the course of the year, with closest approach coming in the middle of winter and the farthest distance in midsummer."

*raise hand*
Mean distance from Earth: 149.6×106 km (92.95×106 mi)

2 points!

The Sun is much closer to Earth than any other star is. The Sun’s nearest stellar neighbor, Proxima Centauri (part of the triple star Alpha Centauri), is 4.3 light-years from our solar system, meaning light from Proxima Centauri takes 4.3 years to reach the Sun. The Sun is so much closer to Earth than all other stars are that the intense light of the Sun keeps us from seeing any other stars during the day.

Earth would not have any life on it without the Sun’s energy, which reaches Earth in the form of heat and light. This energy warms our days and illuminates our world. Green plants absorb sunlight and convert it to food, which these plants then use to live and grow. In this process, the plants give off the oxygen that animals breathe. Animals eat these plants for nourishment. All plant and animal life relies on the Sun’s presence.

Fill in the blanks.

The Milky Way Galaxy contains about ___ billion stars. All of these stars, and the gas and dust between them, are rotating about a galactic center. Stars that are farther away from the center move at _____ speeds and take longer to go around it.

Mithos raises his hand "The Milky Way Galaxy contains about 200 billion stars. All of these stars, and the gas and dust between them, are rotating about a galactic center. Stars that are farther away from the center move at slower average speeds and take longer to go around it."