This shiny book will delight young space enthusiasts with beautiful pictures, vibrant descriptions, and incredible facts. Explore the planets closest to the sun, from Mercury to Neptune, on an unbelievable cosmic tour!
This is the third shiny installment in the wonderfully illustrated Kids Books for Young Explorers series. If your child likes reading playful poems, discovering cool science, and chasing down a galaxy full of fun, then they’ll love Gene Lipen’s sparkling story!
What is the Solar System?
The Solar System is a huge collection of planets, moons, asteroids, dwarf planets and comets. It stretches for millions of miles, and it’s an amazing space adventure that has fascinated scientists since the invention of the telescope.
The Sun is the center of our solar system, and the eight planets – Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune – orbit it in nearly circular orbits. The axis of rotation for all but Uranus and Pluto is almost perpendicular to the plane of their orbits, known as the ecliptic.
There are also billions of smaller objects ranging in size from tenth-millimeter dust particles to large meteoroids. Most of these are found in the asteroid belt, which encircles Mars and Jupiter.
The largest planets are gas giants made mainly of hydrogen and helium. These are the outer worlds of the solar system, and they’re the most massive and least rocky.
What are the Planets?
When we picture the solar system, our minds usually conjure up images of rocky planets with a few moons, a molten core and surface features like valleys, mountains and volcanoes. But that’s just the simplest way to describe the planets.
To explain the way these planets work, we need to look at how they were formed. Astronomers believe that the planets in our Solar System formed out of the ejecta (the ash and dust that formed when the sun exploded).
In their original state, they had no solid surfaces or other features. Instead, they were balls of gas or ice with thin atmospheres made up mostly of hydrogen and helium.
Our Solar System now contains eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Each of these planets is a bit different in size and composition from the others.
What are the Moons?
Moons are natural satellites of the planets and dwarf planets in our Solar System. They come in all shapes, sizes and types and some have atmospheres and even hidden oceans beneath their surfaces.
The majority of planetary moons formed from discs of gas and dust circulating around planets in the early days of our Solar System. However, some are “captured” objects that formed elsewhere and fell into orbit around larger worlds.
Jupiter, Saturn and Neptune each have more than a dozen moons. The reason is that these planets have strong gravitational pulls which attract lots of space rocks and matter towards them.
The moons’ orbits can be pro- or retrograde (against the direction of their planets’ rotation). Some are irregular, and others have elongated, semi-circular or circular orbits.
What are the Stars?
Stars are huge spheres of glowing gas held together by gravity. They are billions of miles away from Earth and can be seen with a telescope.
Stars burn nuclear fuel in their cores, releasing energy as radiation we call light. This is called stellar fusion.
For most of their life, stars are in a state called the main sequence, burning hydrogen fuel and emitting light and heat. The temperature of the inner core is so hot that it can fuse elements like carbon and helium into atoms.
As a star ages, it runs out of hydrogen fuel. It then expands to become a red giant. This process is repeated over billions of years until the star is gone. Larger stars eventually collapse and explode as a supernova, creating a black hole or neutron star.