Six Science posts #82

"Old" formula, colorful Crays, Chicago's superb bridges and more

Author

Harshal Chhaya
August 04, 2025

Six tweets that celebrate engineering and all things STEM.

I scroll so you don’t have to.

A quick fun fact: The first of this month was an interesting date. It has 2 square numbers and 2 cubes - in all formats

  • 8/1/25

  • 1/8/25

  • 8/1/2025

  • 1/8/2025

The last time this happened was on New Year’s day

(I recently learned of a newsletter where you can read it at no cost but replying is limited to paid subscribers. This is NOT that newsletter. You can reply and forward this newsletter for FREE - as many times as you want. 😄 Stay curious, my friends!)

#1 🤯 

This is NASA’s new consolidated social media approach.

If you aren’t on the platform, don’t worry. I will scroll and curate and share so you don’t

#2 🤯 

I found this very fascinating.

Do you agree with Sheel’s formula?

#3 🤯 

It’s really, truly amazing how much computing has gotten faster in our lifetimes.

#4 🤯 

Each of the three name has a fascinating history

1. Mt. Everest is named after Sir George Everest, a British surveyor who served as the Surveyor General of India in the 19th century. The name was proposed by Andrew Waugh, Everest's successor as Surveyor General

2. K2 was named by the survey team because it was the 2nd peak they surveyed in the Karakoram range. It was so remote, that it apparently didn’t have a local name.

3. Kanchenjunga means "Five Treasures of the Snow" in Tibetan and refers to the mountain's five major peaks.

#5 🤯 

From a colorful Cray that only the top universities and research teams could afford to beige boxes on every desk - within 6 years!

#6 🤯 

Reader and friend Chris Woods (@dailystem on X) shared some more impressive details about this bridge:

The bridge carries two railroad tracks across the Chicago River at an angle of about 40 degrees to the center line of the river. Upon completion, the main span could be raised 111 feet (34 m) in about 45 seconds. By 1916, each day the bridge was crossed by about 300 trains, and was raised for river traffic about 75 times.

Check out the bridge’s wikipedia page at https://en.wikipedia.org/wiki/Canal_Street_railroad_bridge for details including a link to the 1915 article from the Journal of the Western Society of Engineers describing the bridge’s design.

(Image of bridge in the header is by By Richie D. from Chicago, IL, USA - Cermak Bridge Barge Passageway, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=5509641)

This is issue #82. Let’s see what makes 82 an interesting number:

  • It is the international calling code for South Korea

  • A semiprime number - product of 2 primes - 41 and 2

  • 82 is a happy number - a happy number is a number which eventually reaches 1 when the number is replaced by the sum of the square of each digit. 82 is a happy number because:

    • 82 + 22 = 64 + 4 = 68

    • 62 + 42 = 36 + 64 = 100

    • 1 + 0 + 0 = 1

  • 82 is palindromic in bases 3 (100013), 9 (1019) and 40 (2240).

  • 82.5 is the longitude used for the time zone in India and Sri Lanka. It is UTC (Coordinated Universal Time) + 5:30

  • 82 is the atomic number for lead, symbol Pb (Latin: plumbum)

    • The amount of lead in the universe is slowly increasing as most heavier atoms (all of which are unstable) gradually decay to lead.

    • The name of the chemical element is not related to the verb of the same spelling, which is derived from Proto-Germanic *laidijan- ('to lead')

  • In science, the sixth magic number.

    • In nuclear physics, a magic number is a number of nucleons (either protons or neutrons, separately) such that they are arranged into complete shells within the atomic nucleus. As a result, atomic nuclei with a "magic" number of protons or neutrons are much more stable than other nuclei. The seven most widely recognized magic numbers as of 2019 are 2, 8, 20, 28, 50, 82, and 126.

    • Note the factoid above that other elements decay to lead - this is because it is a stable element with 82 protons in the nucleus

That’s it for this issue.

Hit ‘reply’ to tell me what you think.

And hit ‘forward’ to share with your friends and family.

Let’s all celebrate science and engineering and curiosity.

Best wishes,

Harshal

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