Science Year 10 Term 3 SPACE

The Universe is everything that exists, including all galaxies, stars, planets, and cosmic matter, spanning over 93 billion light years in diameter.

A star is a massive self-luminous celestial body made of gas, shining through radiation from internal energy sources (nuclear fusion).

A planet is a celestial body that orbits a star, has enough gravity to be spherical, and has cleared its orbit of similar-sized objects.

A celestial body is any natural object in space, such as a planet, star, or nebula.

A galaxy is a massive system of stars, gas, dust, and dark matter bound together by gravity.

A nebula is a giant cloud of dust and gas in space, often a star-forming region.

A black hole is a region of space with gravity so strong that nothing, not even light, can escape.

A constellation is a group of stars forming a recognizable pattern.

The Universe is estimated to be about 13.8 billion years old.

An AU is the average distance between Earth and the Sun (~149,597,879 km).

A light year is the distance light travels in one year, approximately 9.46 trillion kilometers.

The Big Bang Theory proposes that the Universe began from a singular, infinitely hot and dense point around 13.8 billion years ago and has been expanding ever since.

Evidence includes Cosmic Microwave Background Radiation (CMB), the abundance of light elements (hydrogen, helium), and the observed expansion of the Universe.

Hubble’s Law states that galaxies are moving away from us, and the farther they are, the faster they move, indicating the universe is expanding.

Redshift occurs when the wavelength of light from distant objects is stretched toward the red end of the spectrum, indicating that the objects are moving away from Earth.

Planck curves are used to determine the temperature of a star based on its radiation emission.

The Hertzsprung-Russell diagram is used to plot stars by luminosity and temperature, helping to determine their absolute magnitude and evolutionary stage.

the mass, age, temperature, and hydrogen consumption rate of a star determine its fate.

Nuclear fusion is the process by which stars convert hydrogen into helium, releasing energy that powers the star.

Average-sized stars become red giants and then white dwarfs, while massive stars become red supergiants, then explode as supernovae, leaving behind a neutron star or black hole.