Category Archives: The Basics

There are certain basic astronomical facts that everybody should know. I’m talking about stuff like the shape of the Earth, or why a day is 24 hours long. Things that impact our lives at such a basic level that we don’t ever think about them, because they’re part of the everyday fabric of our lives. Most schools will teach you these things at some point, but those lessons are usually short and you don’t always remember them. Maybe you’re still in school and have been asked to find out about these things yourself. Either way, the articles below will explain some of the more basic facts about how the universe works.

How do we know that the Earth is round?

Urban Astronomer avatarPosted on by

There are some things that everybody knows without thinking about.  The sky is blue, apples are red, water is wet, the Earth is round.  But it’s important to regularly question ourselves and check for errors.  It doesn’t take much thought to realise that the sky is usually NOT blue – on overcast days it is grey, at night it’s black, at sunset it can be practically any colour you care to name.  Apples come in green varieties.  When water freezes into ice, or … Continue reading →

Seasons

Urban Astronomer avatarPosted on by

Summer, Autumn, Winter and Spring.    The cycle of the seasons has been known since the dawn of time and human beings all over the world use them to mark moments in their personal histories.  Some people are astonished to learn that the seasons are six months out of phase on opposite sides of the globe, something which amuses us in the Southern hemisphere no end.  But what actually causes seasons?   Many people are dimly aware that the Earth’s … Continue reading →

How do Tides work?

Urban Astronomer avatarPosted on by

    We all learned about the Tides in primary school.  The explanation was always a bit murky, but we knew that the moon was involved.  Sometimes the Sun got involved as well, and then we have spring tides. It was vague, it was oversimplified, and one got the impression that the teachers weren’t entirely sure how it worked either.  Diagrams like the one below only added to the confusion:       It might be of some comfort to … Continue reading →

Phases of the Moon

Urban Astronomer avatarPosted on by

Everybody knows that the Moon changes its face.  Sometimes we have Full Moons, other times it’s a Half-moon, or a crescent, or there’s no Moon at all.  And everybody knows that these are called the phases of the Moon.  But not everybody knows that these faces follow a regular cycle, or that the common descriptions are misleading at best.  A proper understanding of what’s actually happening to make the moon show different faces, and the nature of the “Dark Side … Continue reading →