Topics of Cancer

Oh don’t worry. For a change there won’t be any need for a spell check at least for the title of this post. I like word play, and they do help me with a sparkly header.

Sometimes I feel that I have wasted my high school education completely. We carry on with our life with memories that can be seen as trivial, but when it comes to practical information, the mind definitely starts throwing a tantrum. Back in my school, History, Geography and Civics used to be cumulatively taught under a subject called as Social Science. While Maths used to fail me in its logistics, Social Science kept me company and helped me in shining. So it came as a complete shock to me when I went to Bhopal – the capital city of Madhya Pradesh (M.P.), India and learnt that the practicality of learning Geography has failed me for the first time. I was unaware of the most basic geographical feature of my own country.

You must be wondering what am I blabbering about right? Let me clarify now. I am talking about the Tropic of Cancer, a line of latitude that circles around the Earth at 23.5 degrees north of the Equator.

The newly renovated monument to mark the area where the Tropic of Cancer passes in Bhopal.

Initially I couldn’t understand when my driver kept talking about it in the native language. It has been a while since my ears had the pleasure of listening to Hindi spoken by a true native. Then it hit me. The man is actually talking about the Tropic of Cancer, which has been visibly etched at the Bhopal – Sanchi road as you can see in the pictures below. I would have posed for you guys, but there was a rush of ongoing traffic, and I didn’t want to miss out on Sanchi.

On the other side of the road, repair is still being done.
On the other side of the road, repair is still being done. Do you see the white lines on the road? That’s where the line has been marked

My driver was very helpful in providing these vital information:

  • The Tropic of Cancer, also known as Kark (= Cancer) Rekha (=Line) passes through 14 districts of M.P, namely Ratlam, Ujjain, Shajapur, Rajgarh, Sehore, Bhopal, Vidisha, Raisen, Sagar, Damoh, Katni, Jabalpur, Umariya and Shahdol.
  • It is responsible for the harsh climate that the region of Madhya Pradesh is known for. Summers are extremely hot and starts by February, lasting till July. Monsoon and winter seasons, on the other hand, are known for their short duration.

I wanted to blog about this at that very moment. But I have been told that patience is a virtue, and I decided to note it all down in my Travel diary. Thank god for that moment of sanity, right? It became the perfect fodder for my Featured Post

Now can I tell you some more facts about the Tropic of Cancer in general?

Indian states through which the Tropic of Cancer passes

  1. Gujarat
  2. Rajasthan
  3. Madhya Pradesh
  4. Chattisgarh
  5. Jharkhand
  6. West Bengal
  7. Tripura
  8. Mizoram

The Naming ceremony

At summer solstice (around June 21) when the Tropic of Cancer was named, the sun was pointed in the direction of the constellation Cancer, thus giving the new line of latitude the name the Tropic of Cancer. However, because this name was assigned over 2,000 years ago, the sun is no longer in the constellation Cancer. It is instead located in the constellation Taurus today. For most references though, it is easiest to understand the Tropic of Cancer with its latitudinal location of 23.5°N.

Why is it important?

  • It is used to divide the Earth into different parts for navigation and marking the northern boundary of the tropics, which is the region that extends from the equator north to the Tropic of Cancer and south to the Tropic of Capricorn.
  • It is significant to the Earth’s amount of solar insolation and the creation of seasons.Solar insolation is the amount of incoming solar radiation on the Earth. It varies over the Earth’s surface based on the amount of direct sunlight hitting the equator and tropics and spreads north or south from there. Solar insolation is most at the sub-solar point (the point on Earth that is directly beneath the Sun and where the rays hit at 90 degrees to the surface) which migrates annually between the Tropics of Cancer and Capricorn because of the Earth’s axial tilt.


  • When the sub-solar point is at the Tropic of Cancer, it is during the June solstice and this is when the northern hemisphere receives the most solar insolationDuring the June solstice because the amount of solar insolation is greatest at the Tropic of Cancer, the areas north of the tropic in the northern hemisphere also receive the most solar energy which keeps it warmest and creates summer.
    In addition, this is also when the areas at latitudes higher than the Arctic Circle receive 24 hours of daylight and no darkness. By contrast the Antarctic Circle receives 24 hours of darkness and lower latitudes have their winter season because of low solar insolation, less solar energy and lower temperatures.

Related (and not-so related) Posts:


Madhya Pradesh

24 comments

  1. Thank you Ishita 🙂 so cool to understand these things. In Mexico this Tropic is a big deal too as it moves towards south every year a few millimetres more and it changes dramatically the weather. Thank you so much for this! 🙂 I’m sharing it on my FB page.

    Liked by 1 person

  2. Interesting Post. I copied this from Google and thought you’d find this interesting: El Quelite is located 20 miles north of Mazatlan (where I live) just across the Tropic of Cancer between the SIERRA MADRE MOUNTAINS and the Pacific Ocean. Isn’t that a coincidence?

    Liked by 1 person

  3. Goodness! I don’t think I remember hearing/learning even half of that a century ago in high school! Thanks so much – It’s so good to stretch our brains once in a while.

    Liked by 1 person

Leave a comment