Perihelion, Aphelion & Astronomical Unit

12-Sep-2020: These are the Facts about Perihelion, Aphelion & Astronomical Unit:

The Earth revolves around the sun in an elliptical path, being at one of the foci or focal points. In early January, Earth reaches its closest position to the sun. Astronomers call this point perihelion, and at this time Earth is about 91.4 million miles (147.1 million km) away from the sun, according to NASA. 

Keep in mind that Earth's distance from the sun does not determine the seasons we experience; the seasons are determined by the tilt of the planet's axis. This is why the season occurring in Earth's Southern Hemisphere is always in opposition to the season in the Northern Hemisphere.

Half a year after perihelion, Earth reaches its farthest distance from the sun, which is called aphelion. At that moment, the planet is approximately 94.5 million miles (152.1 million km) from the sun. Aphelion occurs in early July. 

Perihelion and aphelion average out to about 93 million miles (150 million km).

The International Astronomical Union (IAU) is responsible for maintaining and approving a special set of units in astronomy, formally defined in 1976. 

One of the most important of these is the astronomical unit. It is a unit of length approximating the Sun-Earth distance (of about 150 million kilometres) which is of convenient use in astronomy. According to its definition adopted by the XXVIIIth General Assembly of the IAU (IAU 2012 Resolution B2), the astronomical unit is a conventional unit of length equal to 149 597 870 700 m exactly. This definition is valid irrespective of the used time scale. 

The unique symbol for the astronomical unit is au. The IAU also defines other astronomical units: the astronomical unit of time is 1 day (d) of 86,400 SI seconds (s) (SI is the International System of Units) and the astronomical unit of mass is equal to the mass of the Sun, 1.9891×10^30 kg.

Anniversary Vs Event Day

15-Aug-2020 / 73rd or 74th Independence Day

Today our country is celebrating the Independence Day- but there is a controversy whether it is 73rd or 74th. This is the “Off by One” syndrome by computer programming parlance. Let’s analyse and understand it in simple logical steps.

Our country was declared independent on 15-Aug-1947. And today is 15-Aug-2020. Simple arithmetic tells us that the difference is 73 years- it means that today we have completed 73 years and NOT 74 years.

Simultaneously, just today we stepped into the 74th year of Independence. And it will last till 15-Aug-2021, on which day we would have completed 74 years of independence.

Note that 73 or 74 years denotes a ”Duration of Time”, and 73rd or 74th event denotes a “Point in Time”. For people more conversant with Arithmetic, 73, 74 etc. are “Cardinal” numbers, while 73rd,74th etc. are “Ordinal” numbers.

Don’t confuse this two terms which are different. So the correct statement is that on the day of 74th Independence Day we completed 73 years of independence.

Let’s check it: with the same logic on 15-Aug-1947 we celebrated the 1st Independence Day and we completed 0 year of independence. Right? Yes, and the algebraic form are: on (n+1)th event day we complete n years of that event.

Now let’s come to the concept of “Anniversary”. Any event happening for the 1st time is NOT an Anniversary. The counting of anniversary starts a year after. So, on the 73rd Anniversary of our Independence we complete 73 years of independence. And the algebraic form is: on (n)th event Anniversary Day we complete n years of that event.

To summarise, if we use “Anniversary” then number denoting the duration and point are same. But if we don’t use “Anniversary” then number denoting the duration is one less than the number denoting point.

Having explained that, an exception can be stated here. Most people say it’s my 16th Birthday and my age is 16. What they mean is that, it’s my 16th Birthday “Anniversary” and my age is 16. The “Anniversary” word they omit inadvertently to cut the expression short. And that has become a norm, even if it is arithmetically incorrect.

Programmed to Fail

10-May-2020 / Food for Thought:

Please consider these three things:

(1) We, in our country, have a so called very efficient system of governance which is programmed to fail. Some won’t like it, so they are indifferent towards it. Some will simply reject it. Some work overtime to see it fail, so that they can blame the govt. There are still some who half-heartedly carry out without any seriousness. So the result is anybody’s guess.

(2) We are very proficient in post-event analysis. We do a lot of research why this failed, why that went wrong. Very rarely we plan for success. And even if we do the above item no.1 happens.

(3) Convergence: We never work in unison, or to say for a common goal. All the Govt Departments / independent entities / groups / bodies have their own set of goals, which rarely converge. And even at times goals clash with one another. Here’s a classic example: A couple of years ago, when the GoI decided to launch bank FDs for Senior Citizens with an RoI @8% pa, no banks came forward. They said it is not viable. Later LIC of India took up with their own tenets.

If we have developed since independence, it’s not because of the system but in spite of it. We have fortunately a select set of individuals who carry forward the nation against heavy odds.

In A Lighter Note

26-Apr-2020 / In a Lighter Note:

What is a Musk Melon?

Musk Melon or Muskmelon, also known by its scientific name, Cucumis melo, is a type of melon fruit that belongs to the same family as pumpkins, squash, zucchini and cucumbers.

Now let's have some fun: just reverse the positions of the two words. Then remove the 'M' from the first word (after reversal). What did you get? Did it surprise you?

A great, highly successful and billionaire innovator, entrepreneur, motivator.