Solar System and Universe

What is the solar system?

The solar system is a group of celestial bodies, including the Sun, planets, moons, asteroids, comets, and other objects, bound by gravity and orbiting the Sun.

What is a planet?

A planet is a large celestial body that orbits a star, is spherical in shape, and has cleared its orbit of other debris.

What is the geocentric theory?

The geocentric theory is an astronomical model where the Earth is considered the center of the universe, and all other celestial bodies, including the Sun and stars, revolve around it.

What is the heliocentric theory?

The heliocentric theory is an astronomical model that places the Sun at the center of the universe, with the Earth and other planets orbiting around it.

What is a dwarf planet?

A dwarf planet is a celestial body that orbits the Sun, is nearly spherical in shape, but has not cleared its orbit of other debris. Examples include Pluto, Eris, and Haumea.

What is an asteroid?

An asteroid is a small, rocky body that orbits the Sun, mainly found in the asteroid belt between Mars and Jupiter. They vary in size and shape and are remnants from the early solar system.

What is a galaxy?

A galaxy is a massive system that consists of stars, stellar remnants, interstellar gas, dust, and dark matter, bound together by gravity. Examples include the Milky Way and the Andromeda Galaxy.

What is the Moon?

The Moon is Earth's only natural satellite, orbiting the planet and affecting tides. It is the fifth largest moon in the solar system and has various phases and features such as craters and maria.

What is a meteor?

A meteor is the streak of light produced when a meteoroid burns up in Earth's atmosphere. These are often referred to as shooting stars, and they can vary in brightness and duration.

What is a comet?

A comet is a small celestial body made of ice, dust, and rocky material that orbits the Sun. When a comet approaches the Sun, its ice vaporizes, creating a glowing coma and often a tail that points away from the Sun due to solar wind.

What is a star?

A star is a massive, luminous sphere of plasma held together by gravitational forces, primarily composed of hydrogen and helium. Stars undergo nuclear fusion in their cores, producing light and heat, and serve as fundamental building blocks of galaxies

What is the electromagnetic spectrum?

The electromagnetic spectrum is the range of all types of electromagnetic radiation, which includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. Each type has different wavelengths and frequencies, and they travel at the speed of light.

What is apparent magnitude?

Apparent magnitude is a measure of the brightness of a celestial object as seen from Earth, without correcting for the object's distance from the observer. It is a logarithmic scale, where lower numbers indicate brighter objects.

What is absolute magnitude?

Absolute magnitude is the measure of the intrinsic brightness of a celestial object, defined as how bright the object would appear at a standard distance of 10 parsecs (about 32.6 light years) from the observer. It allows for a direct comparison of the true brightness of different stars and other celestial objects.

How does the Sun make its own energy?

The Sun generates energy through nuclear fusion in its core, where hydrogen atoms combine to form helium, releasing an enormous amount of energy in the process. This energy is emitted as light and heat, providing the Sun's luminosity.