SortStack #21 — 2026-06-30

By weight · Order from lightest to heaviest.

1. An adult house mouse 19 g

   Male mice sing ultrasonic courtship songs too high-pitched for humans to hear, with repeated phrases like birdsong.

2. A giant Pacific octopus 30 kg

   It can squeeze its entire body through any gap larger than its beak — the only hard part it owns.

3. A whole wheel of Parmigiano-Reggiano cheese 38 kg

   Italian banks accept aging Parmesan wheels as loan collateral, storing thousands of them in climate-controlled vaults.

4. An adult blue whale 140 t

   The largest animal ever known has a heart the size of a small car, and its calves gain roughly 90 kg per day on milk alone.

5. The International Space Station 420 t

   Assembled over 42 flights, it circles Earth 16 times a day at 28,000 km/h, so its crew sees 16 sunrises daily.

6. An Ohio-class nuclear submarine, submerged 18.8K t

   It displaces more than some WWII aircraft carriers and can stay underwater for months, limited mainly by the food supply.

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