James Webb Telescope/Speed of Light

-

Telescope model
The James Webb Telescope has 18 hexagon-shaped mirrors which fit together like a jigsaw puzzle. This telescope works by detecting infrared radiation from distant objects. Created by NASA, ESA (Europe) and CSA (Canada), it was named after James Webb of NASA who supervised the Apollo program which took humans to the Moon. 

It showed us pictures from a distance of 13.7 billion light years away. So, the conclusion was that the universe is 13.7 billion years old.

Or that the universe was so young back then, it couldn't produce any stars. But, now it is said that Webb could spot a galaxy nearly 30 billion light years away!

Speed of Light

The speed of light is unimaginably fast. Almost 300,000km/s! The distance travelled by light in one year is called a light year, which is 9.6 trillion kilometers. It is one of the largest units used for measuring astronomical distances. Similarly, a light second is the distance covered by light in one second, and a light minute is the distance covered by light in a minute. 

It takes 8 minutes and 20 seconds for light from Sun to reach Earth. Hence the distance between Earth and Sun is 8 light minutes and 20 light seconds.

Sunrise
Sunrise-Mountain view


Also, the Sun we see in real-time is how the Sun was 8 minutes and 20 seconds ago from the moment you look at it. As it takes that much time for the light from the Sun to reach us. Though the Sun is the ultimate energy and light source, the free space is still dark, because light needs an atmosphere to scatter.

Propagation of Light

In order to explain the propagation of light, different theories were put forward by many scientists. Light travelling in straight lines, light as a wave, and even having a particle nature. Let us take a look.

In 1704, Sir Isaac Newton proposed the Corpuscular theory. It states that light is made up of tiny energy packets called corpuscles, which travel in a straight line. But this theory failed to explain diffraction and interference of light. Christiaan Huygens, a Dutch mathematician and physicist, came up with the idea that light does not propagate as a straight line but in waves. And this theory could successfully explain the phenomena which could not be explained by Newton's corpuscular theory.

The photoelectric effect of light shows that light has a particle nature too. 

Note: Contents published here has been taken from various sources for reference purpose. Readers are requested to do their own study before using them in any medium.

Comments

Post a Comment

Popular posts from this blog

Continents and Some of their Interesting Facts

-
Image
Our Earth is divided into seven continents. Millions of years ago, there was a single continent called Pangea, which was covered by an Ocean called Panthalassa. Eventually, the supercontinent broke apart to form the different continents that we have today. Here are some interesting facts about them. Africa Africa is the 2nd largest continent in the world. Its total land area is 3,03,65,000 sq.km. Africa is surrounded by the Atlantic Ocean, Mediterranean Sea, Red Sea and Indian Ocean. It is the only continent through which the Equator, Tropic of Cancer and Tropic of Capricorn passes!   Nile River  Africa is also known as the " Cradle of Humankind ". There are 54 countries in Africa. The Nile, the longest river in the World and the Sahara, the largest hot desert in the world is in Africa. Africa produces about 70 percent of the world's cocoa beans. Asia Asia is the largest continent in the world. It is surrounded by the Arctic Ocean, Pacific Ocean, Indian Ocean, and Red Sea
Read more

Parassinikkadavu Muthappan Temple-Here you can Chat with God

-
Image
Temple view from Valapattanam River  Lord Muthappan Temple of Parassinikkadavu is a very famous temple. It is situated on the bank of Valapattanam River, in Parassinikkadavu in Kannur district. Parassinikkadavu is a small town, approximately 19-20 km away from Kannur City. To visit the temple and to see the Muthappan, departed from the hotel at early morning. About 6.15 am we got the line bus to the Kannur KSRTC station ( Kerala State Transport Corporation). We reached the station by 6.30 a.m and by 6.45a.m we got the State Transport bus to the Parassnikkadavu . The bus charge to Parassinikkadvu from Kannur Transport Bus station was Rs.25.00 The bus took almost 30.minute to reach at Parassinikkadavu. From there you have two option to reach the temple. Option one is to hire an  Auto rickshaw  and other option is to walking up to the temple. As I was travelling with elders and they had the difficulty to walk, we preferred to hire an Auto rickshaw. The road to the temple was very beautifu
Read more

Standard/Metric Conversions and Roman Numerals/World Currencies

-
Image
We are using several measurements in our day to day life. Unit of measurements vary from its actual usage and field of application. Please find the details below. Inch x 25.4 = Millimetre Foot x .3048 = Metre Yard x .9144 = Kilometre Acre x .4047 = Hectare Quart x .9463 = Litre Gallon x .004 = Cubic Metre Ounce x 28.3495 = Gram Pound x .4536 = Kilogram Degrees Farenheit x 5/9-32 = Degrees Celsius Millimetre x .0394 = Inch Metre x 3.2808 = Foot Metre x 1.0936 = Yard Kilometre x .6214 = Mile Hectare x 2.4710 = Acre Litre x 1.0567 = Quart Cubic Metre x 284.2 = Gallon Gram x .0353 = Ounce Kilogram x 2.2046 = Pound Degree Celcius x 9/5 + 32 = Degrees Farenheit ROMAN NUMERALS Roman  Numerals are unique and are very stylish. We can see it almost everywhere in our daily life. It is very much common on wrist watches and on wall clocks. Some of those numerals are given below for reference. Clock with Roman Numerals I =  1      II =  2  III = 3 IV = 4 V = 5 VI = 6 VII = 7 VIII = 8 IX = 9 X = 10 X
Read more