The corona is a. 300 times cooler than the surface of the Sun b. 300 times hotter than the surface of the Sun c. 300 times cooler than the surface of the Earth
On Earth, coronal mass ejections can cause a. severe storms b. extremely high temperatures c. damage to the power grid
The corona is only visible during a. a CME b. a solar flare c. a total solar eclipse
Discussion/essay questions
In 1859, a CME caused telegraph stations around the world to burn out. Because we depend so much on technology, a CME of the same size today would cause major damage. What do you think the world would be like without any modern technology?
Transcript
The outer atmosphere of the Sun is called the corona. It is a thin layer of charged gas that extends for millions of kilometres. It is actually about 300 times hotter than the Sun’s surface, which is an ongoing puzzle for scientists. The corona is a chaotic environment, and it sometimes releases large amounts of magnetic matter into space. This is called a coronal mass ejection, or CME. Scientists monitor CMEs because they can damage the power grid on Earth. Most of the time, the corona is impossible to see with the naked eye. The surface of the Sun is so bright that it completely outshines the light from the outer layers. However, the corona can be seen briefly during a total solar eclipse, when the Moon obscures the Sun from view.
The inner disk of the Oort Cloud is also called a. the Hills Cloud b. the Kuiper Cloud c. the Neptunian Ring
Most of the objects in the Oort Cloud are a. asteroids b. comets c. gas planets
Sedna is the name of a. the moon that orbits Pluto b. a far dwarf planet in the inner Oort Cloud c. a comet with an orbit of millions of years
Discussion/essay questions
Some people make wishes on comets and meteors in the sky. The planets in the solar system are named after ancient gods. Why do you think humans see magic in space?
Transcript
The Oort Cloud is a cloud of small icy objects at the very outer edge of the solar system. It is thousands of astronomical units away from the Sun. It is made up of an inner disk, called the Hills Cloud, and an outer sphere, which surrounds the entire solar system. Scientists believe that the Oort Cloud formed in the early days of the solar system, when the strong gravity of the gas planets pushed other matter far away. The outer Oort Cloud contains the farthest objects that are trapped in the Sun’s gravity. Most of these objects are comets, which can take millions of years to orbit the Sun. However, the Hills Cloud also contains dwarf planets similar to Pluto. One of these dwarf planets, called Sedna, may be the farthest planet-like object in the Sun’s orbit.
Do you believe in life on other planets? Why or why not?
Do you think that aliens could be discovered in our lifetime?
Transcript
An exoplanet is a planet outside of our solar system. Most exoplanets orbit different stars in the galaxy. However, astronomers have observed some planets that are independent of any star system. The first two exoplanets were discovered in 1992. Since then, scientists have been searching for exoplanets that are similar to Earth. This might lead to the discovery of alien life. However, Earth-like planets are difficult to find, because the resources necessary for life only exist under very specific conditions. Our planet happens to be in the solar system’s habitable zone, where the temperature allows water to exist in liquid form. There are over 1,700 known exoplanets, and only 16 of them are potentially habitable.
