A follow-up to "Six Science posts #89"

Another "89" fact and a more measured celebration of the Haber process

Author

Harshal Chhaya
October 02, 2025

Hi friend,

I have a follow-up to a couple of things in issue #89 of the newsletter 

1.

Post #3 of the newsletter mentioned the Haber process which makes fertilizer production more efficient and has resulted in significant improvement in agriculture yield.

A reader, FF, alerted me to the fact that the process is not all good. There’s some pretty bad side-effects of the process.

Part of the problem is that the conventional Haber-Bosch process is bad for the environment because it's highly energy-intensive, consumes a significant amount of global energy, and is a major source of greenhouse gas emissions, including CO2 and N₂O.

However, there are mitigations.

Also, this experience is similar to a few other scientific discoveries - the initial impact of the solution is lauded as the “best thing ever” but subsequent research shows significant side-effects that were either unknown or ignored during the original research.

A few other examples I can think of are DDT, leaded petrol, asbestos and more.

This is a cautionary tale that any “perfect solution” might have secondary problems that may not be evident initially.

2.

As with previous issues, issue #89 had a pretty fun list of facts about the number 89.

Here’s what it said:

89 is

  • the atomic number of Actinium, a chemical element, symbol Ac

    • The actinide series, a set of 15 elements between actinium and lawrencium in the periodic table, are named for actinium.

    • the introduction of the actinides in 1945 was the most significant change to Dmitri Mendeleev's periodic table since the recognition of the lanthanides

    • Owing to its strong radioactivity, actinium glows in the dark with a pale blue light, which originates from the surrounding air ionized by the emitted energetic particles

    • The name actinium originates from the Ancient Greek aktis, aktinos , meaning beam or ray.

  • the 24th prime number, following 83 and preceding 97.

  • a Pythagorean prime - a prime number of the form 4 n + 1

    • Pythagorean primes are exactly the odd prime numbers that are the sum of two squares

    • In this case: 89 = 52 (25) + 82 (64)

  • The 11th Fibonacci number and thus a Fibonacci prime as well.

  • There are exactly 1000 prime numbers between 1 and 892 =7921.

    (Harshal: This is such a cool and interesting and kind of pointless fact. I love it! 😀 )

  • There is no country with 89 as its international calling code

But wait there’s more…

Hellin's law, also called Hellin-Zeleny's law, is an empirical observation in demography (study of human populations) that the approximate rate of multiple births is a power of 89. So, twin births occur about once per 89 singleton births, triplets about once per 892 , quadruplets about once per 893 , and so on.

And you thought 89 was just another number! 😄 

That’s it for this update, folks.

Stay curious! And share this newsletter with friends and family and everyone who would appreciate staying informed and entertained.

Love,

  • Harshal