Cosmology itself deals with modern complex theories of physics. But cosmology is a beautiful subject. Once you started to study you will want more. It can help you to think differently. So let me tell you about cosmology simple and clear as anyone of you can understand.
What is cosmology?
Cosmology was the study of the origins of our universe. But with time passing by, now we have a proper definition for it. As NASA (National Aeronautics and Space Administration) says, Cosmology is “the scientific study of the large-scale properties of the universe as a whole.”
The most preferred theory for the beginning of the universe is the big bang theory. But there is not only one existing universe for the multiverse theory. There are other ideas like string theory. All these are part of cosmology today.
History of cosmology
The history of cosmology ran back to the beginning of civilizations. Religions have their own explanation for how the universe and earth started. One famous explanation still believed today is creationism. It says an intelligent creator (A God) created the entire universe.
Astronomers in early ages believed the Sun and planets orbit around earth. Nicolaus Copernicus first stated that the earth is orbiting around the sun in 1543. But it was not largely accepted until a century. However, In the 17th century, Sir Isaac Newton introduced the inverse-square law of universal gravitation. He could explain the motion of the solar system by gravity.
In the 19th century, we only knew the existence of the milky way until Edwin Hubble. In 1923, he resolves a debate called ‘Shapley–Curtis’ and proved there were other galaxies beyond the milky way.
Just like that once considered the whole universe became a group of stars. Albert Einstein invented the general theory of relativity. Dark energy was discovered in 1998. String theory was invented in 1968.
The truth behind beautiful images of cosmology
With the help of telescopes located on the Earth and space, scientists try to understand the origins of the universe and the reality of nature. People can see some of those pictures of stars, planets, and galaxies. Many usually find these beautiful and interesting.
Why are they colorful or colorless?
Technically most of the light observed by these telescopes is invisible to the human eye. So, they have no color. But we have to transfer those to a form that the human brain can process. Otherwise studying them will be impossible.
We only see a fraction of the electromagnetic spectrum called visible light. But telescope data contains infrared and x-rays. So, scientists need to colorize these pictures. They do that by referencing colors to selected wavelengths of the telescope data and assigning colors for other wavelengths. A simple method is giving red for the longest wavelength, green for medium, and blue for the highest wavelength. So, after this process, we can get a colorful image.
Astronomers can analyze these pictures. They identify Certain things like temperature and places where new stars are birthing. So, these beautiful cosmology images have really important uses.
Beautiful things in space
The heart of M16 also known as the Eagle Nebula is a cloud of gas and dust which 7000 light-years away from earth. In 1995, the Hubble telescope captured a beautiful image of the eagle nebula, and it was astounding by it. There are three gaseous columns in the famous picture known as ‘Pillars of Creation. Studying the birth of stars in the eagle nebula helps us to understand how our solar system was created.
The mystic mountain is an area of Carina Nebula. The Hubble telescope image of it has the same name. Mystic Mountain is located 7500 light-years away from earth. It has 3 light years in height. It contains a large number of stars that fire off getting gases.
This planetary nebula got its name from a creature in Greek mythology. Just like how dreadful Gorgon Medusa is, the Medusa nebula has a dreadful beauty. It is in the constellation Gemini. It is 5400 light-years away from earth.
Messier 101 also known as Pinwheel galaxy is belonged to the Ursa Major constellation. Pinwheel galaxy is 21 million light-years away from earth. It is larger than the milky way (100 000 light-year diameter) with 170 000 light-years diameter. It was the most detailed picture taken with the Hubble telescope at that time.
The future of beautiful cosmology with the James Webb telescope
The Hubble telescope retired after more than 30 years of being active. During that time scientists discovered many new things. Beautiful interstellar pictures were taken. Now to fill the gap it left behind, and even more capable James Webb telescope was launched on 25th December 2021. With a 6.5m diameter aperture and 0.6 to > 27 microns wavelength coverage, it is the most powerful telescope launched into space. On March 16, 2021, NASA took the first image from it.
We don’t know what it will do with all those powerful hardware. But we know the James Webb telescope will help scientists to solve some mysteries in beautiful cosmology.