Introductions


Uranus at Opposition

Opposition

In positional astronomy, two astronomical objects are said to be in opposition when they are on opposite sides of the celestial sphere, as observed from a given body (usually Earth). A planet, asteroid, or comet…


Galaxy Cluster Apparent Magnitude

Galaxy Clusters and Superclusters

Previously we have talked about the different galaxy types, and it got us thinking about structures that could be larger than the single galaxy? The answer is galaxy clusters and superclusters. Galaxy Clusters A galaxy…


Dark Matter

What Is Dark Matter

In the standard model of cosmology, the total mass–energy of the universe is said to contain 5% of ordinary matter and energy, 27% of dark matter, and 68% of what is known as dark energy. This article will only touch the surface of…


Double Stars

Double Stars

In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes. The first double stars…


Space Law Space Policy

Space Policy: An Introduction

Space policy can be defined as the political decision-making process for, and application of, public policy of a state regarding spaceflight and uses of outer space, both for civilian, scientific and commercial, and military purposes. This is significantly…


Space Weather

Space Weather: An Introduction

The technical definition of space weather can be said to be a branch of space physics and aeronomy concerned with the time varying conditions within the Solar System. It is worth noting that these features are distinct from but…


Atmosphere Atmospheric Science

The Atmosphere Of The Earth: An Introduction

The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth’s gravity. The atmosphere of Earth protects life on Earth by creating pressure allowing for liquid water to exist on the Earth’s surface, absorbing ultraviolet solar radiation, warming the…


Gravitational Waves

Gravitational Waves: An Introduction

Gravitational Waves can be defined as disturbances in the curvature of spacetime, generated by accelerated masses, that propagate as waves outward from their source at the speed of light. This means that gravitational waves transport energy as gravitational radiation, which is…


Gravity Assist

Gravity Assist: The Basics

In orbital mechanics and aerospace engineering, a gravity assist is the use of the relative movement and gravity of a planet or other astronomical object to alter the path and speed of a spacecraft, typically to save propellant and reduce expense. The origins of a gravity assist can trace its origins to the…