Understanding the basics of Astronomy literally opens up a new world. The scale of the universe is mindboggling with billions of stars, planets, and celestial bodies. Mythical constellations beckon the Astronomer to listen to their own story. Astronomy it appears is infinite. To begin Astronomy is in fact very easy to do in fact nearly anybody can begin.
To begin Astronomy
All you need to view the stars and constellations are dark skies, it’s as simple as that! Light pollution can block out weaker stars and spoil your astronomical delight whereas a dark-site such as a local park or in the countryside is a choice location.
Most people have in their possession a basic set of binoculars. These can be used to view the night sky, either by being hand-held or mounted onto a tripod.
Constellations
Two of the easiest constellations that most people recognise are Orion’s Belt and The Big Dipper or Great Plough depending on your location and language.
Having located these two constellations you can begin discovering more. For example you can find Polaris (the North Star) very easily by following in a line the 2 last stars of The Big Dipper (Merak and Dubhe) until you find the next brightest star. This celestial north pole is also the Earth’s north pole too.
Planets
You will be surprised but often the brightest objects in the sky are not stars but actually planets. Venus, Saturn and Jupiter can all be seen with the naked eye. Even the brightest moons of Saturn and Jupiter can be seen with large binoculars.
Magnitude and the measurement of brightness
Magnitude is used as a measurement for showing how bright a star is. There are two kinds Apparent and Absolute. Apparent magnitude is the brightness as seen from Earth. The Absolute magnitude is the brightness if seen at a distance of 10 parsecs (32.616 light years). Magnitude is indicated as the brightest object having the lowest number even into minus figures.
So for example the middle star in Orion’s Belt called Alnilam has an apparent magnitude of 1.65 whereas Sirius the dog-star has an apparent magnitude of -1.46 and is therefore brighter.
The Speed of Light
The speed of light is used as a measurement in space. It is 186,000 miles-per-second (300,000 kilometres per second). If we look at Sirius the dog-star, it is the only star that appears to flicker different colours its distance is 8.6 light years from the earth.
The size of the Universe
The size of our Milky Way Galaxy is approximately 100,000 light years in diameter and contains 200-400 billion stars. It is estimated that there are up-to nearly 500 billion galaxies within the universe each containing hundreds of billions of stars. So you can see the math gets huge when talking about Astronomy.
Stellarium free Software
A great piece of software for your computer is a free virtual planetarium called Stellarium. It can show you all the constellations, nebulas, planets, and galaxies. Its most striking feature is that it can generate art for each of the constellations and show you the lines of its structure. Its a handy way to learn more about the night sky.
By understanding the basics of Astronomy you can understand how our planet exists within the universe. Furthermore the apparent complexity of the constellations will have begun to unravel. What at first seemed like millions of points of light will begin to take shape. You have also learnt how very little equipment you need to begin your journey into astronomy and the vastness that is the universe.
Resource:
http://www. universetoday.com/30305/how-many-galaxies-in-the-universe/
