Scientific Views of the Universe
What is a model?
A representation of an idea, object, or system.
What is the age of the universe?
About 13.8 billion years old.
What causes day and night?
The 23.5 degree tilt of Earth as it rotates around the Sun.
What is the third planet?
Earth.
What is a scientific theory?
An explanation of how or why something happens, with many observations and repeat testing until it is confirmed.
What is the Big Bang Theory?
A singular mass that is a tiny, hot dense point that exploded and continues to expand the universe.
What are galaxies?
A giant system in space made of billions or even trillions of stars, along with dust, gas, and planets, all held together by gravity.
What is a solar eclipse?
It happens when the Moon passes directly between the Sun and the Earth, blocking the Sun's light and casting a shadow on the Earth.
What is the asteroid belt?
A region in our solar system located between the orbits of Mars and Jupiter that contains millions of rocky, airless bodies called asteroids.
How has the solar system changed?
By the Sun's gravity pulling the planets into orbit, while other pieces of dust and gas formed asteroids, comets, and dwarf planets like Pluto.
What does Hubble's Law state?
A galaxy's speed, as it moves away from us (its velocity), is directly proportional to its distance.
What is cosmic background radiation?
The leftover heat and light from the Big Bang (the event that created our universe).
What is a lunar eclipse?
It happens when the Earth moves directly between the Sun and the Moon, casting a shadow on the Moon.
What is the Kuiper Belt?
It is a huge, cold ring of icy, rocky objects and comets that orbits the Sun beyond the planet Neptune.
What evidence supports the Big Bang?
Cosmic microwave background, red shift, and light elements.
What is a light year?
A unit that measures distance, not time.
What is stellar evolution?
The life story of a star, from its birth in a cloud of gas and dust to its eventual death, like a white dwarf or a supernova.
What is the gravitational pull?
A natural force that pulls any two objects with mass toward each other.
What is the heliosphere?
A giant bubble of particles and magnetic fields created by the Sun that surrounds and protects our entire solar system.
What is a hypothesis?
A testable "educated guess" about the outcome of a science experiment, often stated in an "If, then, because..." format.
What is dark matter?
An invisible substance that doesn't shine, absorb, or reflect light.
What is a supernova?
A giant, super-powerful explosion that happens when a star dies.
What is the Moon's orbit?
Its a repeating path as it travels around the Earth.
What is the Oort Cloud?
A giant, spherical bubble of icy, comet-like objects that surrounds our entire solar system.
What is peer review?
When classmates read each other's work, like an essay or a project, and give constructive feedback to help them make it better.