๐ญ โข Lesson 3.9 : Space Physics, Solar System, Universe (Phys) Flashcards
For this final lesson, we will finish by mastering our Solar System, the belts, the stars and the universe, the life cycle of stars, the Milky Way and other galaxies.
What is the Solar System made up of?
The Solar System contains one star (the Sun), eight planets, minor planets (like dwarf planets and asteroids), and moons that orbit the planets
What are the 8 planets in the Solar System, in order from the Sun?
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
What are minor planets in the Solar System?
Minor planets include dwarf planets like Pluto and asteroids in the asteroid belt, which orbit the Sun.
What are moons in the Solar System?
Moons are natural satellites that orbit the planets in the Solar System.
What is the closest star to Earth?
The Sun is the closest star to Earth.
How are astronomical distances measured?
In light-years, which is the distance light travels in one year.
How do you calculate the time it takes light to travel a significant distance?
You can calculate the time using the speed of light and the distance between objects (distance = speed ร time).
Why do the planets orbit the Sun?
The Sun contains most of the mass in the Solar System, causing gravitational attraction that keeps the planets in orbit.
What is the equation for orbital speed?
The orbital speed is given by v = 2ฯr/T,
Where r is the radius of the orbit and T is the orbital period.
What force keeps an object in orbit around the Sun?
The force that keeps an object in orbit is the Sunโs gravitational attraction.
How does the Sunโs gravitational field affect orbital speed?
The Sunโs gravitational field weakens with distance, causing the orbital speeds of planets to decrease as they move farther from the Sun.
What is the Sun made of and what type of energy does it radiate?
The Sun is mostly made of hydrogen and helium and radiates energy in the infrared, visible, and ultraviolet regions of the electromagnetic spectrum.
How are stars powered?
Stars are powered by nuclear fusion, where hydrogen is fused into helium, releasing energy.
How are stable stars formed?
Stable stars form from interstellar clouds of gas and dust, which collapse under gravitational attraction to form protostars.
How can a nebula from a supernova form new stars?
A nebula from a supernova can collapse and form new stars with orbiting planets.
What happens to a star with a small mass (about the mass of the Sun)?
A small mass star becomes a red giant, then evolves into a white dwarf surrounded by a planetary nebula.
What happens to a star with a large mass?
A large mass star becomes a red supergiant, then a supernova, and can turn into a neutron star.
What happens to a star with a very large mass?
A very large mass star becomes a red supergiant, then a supernova, and may turn into a black hole.
What are galaxies made of?
Galaxies are made up of many billions of stars.
Where is the Sun located?
The Sun is a star in the Milky Way galaxy.
What does the Big Bang Theory state?
The Big Bang Theory states that the Universe expanded from a single point of high density and temperature, and it is still expanding.
The Universe is approximately 13.8 billion years old.
How large is the Milky Way galaxy?
The Milky Way galaxy is about 100,000 light-years in diameter.
