Six Science posts #79

Uluru from space, 1st Indian on the ISS, the perfect date and more

Author

Harshal Chhaya
June 29, 2025

Six tweets that celebrate engineering and all things STEM.

I scroll so you don’t have to.

(Thanks to the reader who asked about past special topic-specific issues. I have added a list of links at the bottom. Is there a specific topic you would like to have an entire issue on? Hit “reply” and let me know.)

#1 🤯 

Group Captain Shubhanshu Shukla, who's piloting the mission, has become only the second Indian to travel to space. His trip comes 41 years after cosmonaut Rakesh Sharma became the first Indian to fly to space aboard a Russian Soyuz in 1984.

#2 🤯 

NASA and ISRO have a long-standing relationship built on a shared vision to advance scientific knowledge and expand space collaboration. The experiments that will be done during this mission include regenerating muscle tissue, sprouting seeds, microalgae growth, improving electronic interactions and research on tardigrades.

More details:

https://www.nasa.gov/missions/station/iss-research/nasa-isro-research-aboard-fourth-private-astronaut-mission-to-station/

#3 🤯 

We have a robot on another planet! 🤯 

There are cathedrals everywhere for those with the eyes to see.

#4 🤯 

Think of our radio and TV signals expanding outward like a cloud of human culture. As we move more and more to streaming and less over the air broadcasts, will the cloud become less dense over time? When will the aliens conclude if the signals weaken?

#5 🤯 

Commander Hadfield isone of the pioneers of sharing his observations from space directly with the rest of us. His viewpoint and views are unparalleled.

#6 🤯 

A “perfect” number is the sum of its divisors - so both 6 and 28 are perfect numbers.

6/28 is also called “Tau day” because it’s 2*pi (2 × 3.14)

I hope you all ate 2 pies yesterday. Because stopping at just one is irrational.

This is issue #79. Let’s see what makes 79 an interesting number:

  • 79 is a prime number and also an “emirp” because it’s reverse - 97 - is also prime

  • 79 is a right-truncatable prime, because when the last digit (9) is removed, the remaining number (7) is still prime.

  • 79 is a sexy prime (with 73) (i.e. a prime that’s 6 away from another prime. 😀 )

  • In 79 AD, Mount Vesuvius, a stratovolcano located in the modern-day region of Campania, Italy erupted, causing one of the deadliest eruptions in history. The event destroyed several Roman towns and settlements in the area. Pompeii and Herculaneum are the most famous examples.

  • 79 is the atomic number of Gold, chemical symbol Au (from Latin “aurum”). It is one of the least reactive chemical elements. Gold is the most malleable of all metals. It can be drawn into a wire of single-atom width, and then stretched considerably before it breaks.

  • For international calling, “79” is a reserved prefix in Russia

About

This newsletter is my way of sharing interesting science-related news with my curious friends. I enjoy finding science and math connections in our world.

Please share this newsletter with others. Let’s encourage curiosity.

- Harshal (@hschhaya on X/Twitter)

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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