The Sun and Solar Energy

What is the source of light and heat for the solar system?

The sun

What process occurs at the core of the sun?

Nuclear fusion

What two elements fuse together in the sun's core?

Hydrogen atoms

What is the estimated temperature of the photosphere?

Between 5500°C and 6100°C

What layer of the sun appears reddish in color?

The chromosphere

What is the outermost layer of the sun's atmosphere called?

The corona

What causes the grainy appearance of the sun?

Convective currents

What is the speed of solar wind?

About 400 kilometers per second

How long does solar wind take to reach Earth?

More than 4 days

What are the charged particles from the corona mainly composed of?

Protons and electrons

What protects Earth from solar winds?

Earth's magnetic field

What phenomenon occurs when solar winds energize ions in the atmosphere?

Aurora

What are the northern and southern lights called?

Aurora Borealis (Northern lights) Aurora Australis (Southern lights)

What are sunspots?

Dark regions on the sun's photosphere, cooler than surrounding areas

What is the temperature range of sunspots?

About 1500°C to 2000°C cooler than the sun's surface

Who began recording sunspots in the 1600s?

Galileo

How long is the sunspot cycle?

Approximately 11 years

What is the peak year for the next sunspot cycle?

Around the year 2012

How long can an individual sunspot last?

From less than a day to up to 6 months

What is a proposed effect of minimum sunspots?

Times of cooler temperatures

What occurs during a solar eclipse?

The Moon passes between the Sun and Earth, casting a shadow on Earth, blocking the Sun’s light partially or fully.

How often does eclipse season occur?

Eclipse season happens twice a year.

What should you use to view the Sun during an eclipse?

Eclipse glasses or a safe solar viewing method like a pinhole projector.

What is a total solar eclipse?

The Moon completely blocks the Sun, observed as a darkening sky and visible corona.

What can be seen during a total solar eclipse?

The Sun’s corona, the outer atmosphere of the Sun.

What is an annular solar eclipse?

The Moon is farther from Earth and appears smaller, creating a ring of sunlight around it.

What happens during a partial solar eclipse?

Only part of the Sun is covered, giving it a crescent shape.

What is a hybrid solar eclipse?

An eclipse that shifts between annular and total as the Moon’s shadow moves across Earth.

What happens during a total lunar eclipse?

The Moon moves into Earth's umbra, sunlight scatters, and the Moon appears reddish or orangish due to longer wavelengths passing through the atmosphere.

What causes the red color of the Moon during a total lunar eclipse?

Shorter wavelengths scatter away, allowing longer wavelengths like red and orange to reach the Moon.

What is a partial lunar eclipse?

An imperfect alignment results in the Moon passing through part of Earth's umbra, partially shadowing it.

What is a penumbral eclipse?

The Moon travels through Earth's penumbra, dimming slightly and often unnoticed.

When do lunar eclipses occur?

Lunar eclipses occur during the full moon phase when Earth is between the Moon and Sun.

How does atmospheric dust affect the Moon's appearance during an eclipse?

More dust or clouds in the atmosphere can make the Moon appear redder during the eclipse.

What is the visibility of a lunar eclipse?

Each lunar eclipse is visible from half of Earth.