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Cosmos - Astronomy

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Introduction to Cosmos - Astronomy

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The enigma of the universe is fascinating yet intimidating. Scientific research has attempted to uncover the mysteries of the universe, but there is a long way for humanity to grasp even a fraction of the observable universe. Astronomy is the branch of science that engages with the observable universe's components and physics: stars, planets, galaxies, etc. On the flip side, Cosmology is the physical study of the universe from its earliest form during the Big Bang till contemporary times. It is an amalgamation of Astrophysics and Physics manifested to examine the nature of the universe. Cosmology's exciting aspect is that the discipline may even circumscribe religious and philosophical contemplation of the cosmos and nature. Anaximander is both known as the 'father of Astronomy' and the 'father of Cosmology.'

Cosmos – You can define the cosmos in astronomy as the complex and orderly arrangement of the universe. Ancient Greek philosopher - Pythagoras- first used the term to represent the order of the universe. The word 'cosmos' became a part of modern vocabulary after Geographer Alexander Von Humboldt extracted it from ancient Greek texts and named his five-volume Magnum Opus – Kosmos. Thus, Cosmos refers to the entire physical universe as a unified whole. 

We use the word cosmos and universe most of the time interchangeably. But there are differences. "Cosmos" in astronomy is the harmonious and orderly whole, a system that is governed not by human or supernatural laws but by natural law. In astronomy, cosmos refers to objects that exist naturally, especially those visible in the sky. The term "cosmos" has two derivatives. It stems from the Greek word "kosmos", meaning "order, good order," or "orderly arrangement". The second meaning is from the verb "kosmein", which means "arrange" or "adorn", which is derived and passed on to the English language.

On the contrary, "Universe" is defined as "everything that exists including all matter and energy, the Earth, and everything in it together with extraterrestrial or celestial bodies such as the galaxies, stars, meteors, and everything that you can find in intergalactic space." It is everything that existed, that is existing, and will live in the future. The universe has three elements: space and time or the vacuum, matter and energy that occupy space and time, and the physical laws that govern them, which have been constant throughout history.


A Star Gazer's Guide to the Cosmos

Stargazing is a better-known title for the term amateur astronomy. People who do not have scientific backgrounds primarily engage in stargazing. They are interested in observing the stars and other celestial bodies for their pleasure and peace of mind. Many people are incredibly passionate about stargazing. If you are looking to indulge in stargazing yourself, compiled below is a stargazer's guide to the cosmos.

1. Place - Your stargazing experience will be altered drastically by where you position yourself. There are some fantastic places to stargaze on earth, but there are some places you should avoid as well. Starting local is the optimal way. If you live in a city, a very high rise building is a suitable option. It is recommended that you travel out of the town if possible to get an immersive and wholesome experience of stargazing. If you reside in a rural area, congratulations, you can stargaze from any open field. A 360-degree view enables us to observe the horizon (hills or summits) and see many more celestial objects in the sky. So, it would help if you avoided any areas where there are too many trees close by.

2. Types of Equipment – Binoculars are an affordable way to start stargazing for beginners. Then you can move towards the telescope and other hi-tech eyepieces. Apps like NASA, Star Walk 2, Star Chart, etc., should be downloaded for a better experience. It would help if you took other things like a portable table, thermos, notebook, pen, observing stool along.

3. Seasons - The best seasons to go stargazing are autumn, winter and spring as the atmosphere is crisper and there is better long-distance. Also, the sky gets dark faster during these seasons of the year. Hence, the observing time increases during these seasons of the year. It is noteworthy to mention that it takes roughly 1 hour to 1.5 hours to get genuinely dark after sunset when the best observing begins. The further north you live, the longer it will take for true darkness to arrive after sundown. Always check the weather forecast as conditions can always change at a moment's notice.

Celestial Objects to Look For in the Night Sky 

  • Sirius - It is the brightest star in the Northern hemisphere. The most shining star in the sky is Sirius; also known as the "Dog Star" (It is Kepler's favourite one).

  • The Moon - Earth's very own satellite looks epic when viewed with binoculars; the craters appear so much more detailed, it is a sight to behold. 

  • Mars - it is called the red planet for a reason, and it's so cool to be able to see the colour through binoculars. It's too far away to pick out any crucial details with binoculars, but you can still see the red glow.

  • The Milky Way (the Galaxy we Live in) - The Milky Way galaxy sits low in the sky during winter and high in the summer, but it's beautiful whenever you're viewing it.

  • Ursa Major – The term 'Ursa Major' loosely translates to the 'great bear' in Latin. It is the third-largest constellation, and its brightest stars form the Big Dipper. To find the Ursa Major constellation, look for seven stars shining in the shape of a saucepan. It is noteworthy to mention that the Big Dipper is the tail of a bear, so you are looking for a tail, a head and a body.

Cosmos in astronomy is a fascinating subject. It is a warehouse of knowledge, and there is a lot to investigate and understand. Stargazing is a viable technique to understand cosmos, astronomy and our universe practically. A stargazer's guide to the cosmos begins with curiosity and by asking questions.