Astronauts grow taller in space.

Without gravity compressing the spine, astronauts can grow up to about 3% taller. They return to normal height after coming back to Earth.

2017The oldest known written zero is in an Indian birch-bark manuscript.

Carbon dating published by the Bodleian Library in 2017 placed parts of the Bakhshali manuscript, which uses a dot for zero, centuries earlier than previously thought.

Why it happens

Writing zero as a symbol was a big step: it lets a numeral system show “nothing in this place”, which is what makes place-value numbers (10, 101, 1,000) work. Indian mathematicians developed a place-value decimal system that used a dot, later a small circle, for zero.

How we know

The Bakhshali manuscript was found in 1881 in a field near Peshawar (now in Pakistan) and is kept at the Bodleian Library in Oxford. In 2017 radiocarbon dating showed its 70 birch-bark leaves come from different periods, the oldest from the 3rd or 4th century CE. That made its dot-for-zero hundreds of years older than the zero carved at the Chaturbhuj temple in Gwalior (876 CE). Some scholars question whether the oldest leaves date the writing itself, so the exact date is still debated.

Did you know?

The mathematician Brahmagupta set out rules for calculating with zero in 628 CE, including that a number minus itself is zero. These ideas reached Europe through Arabic scholars, which is why we call our digits “Hindu-Arabic numerals”.

A group of owls is called a parliament.

Collective nouns for animals are often playful: a parliament of owls, a murder of crows, a tower of giraffes and a flamboyance of flamingos. Many date back to hunting books from the 15th century.

Turmeric has been used in India for about 4,000 years.

Archaeological evidence from potsherds uncovered in Harappa and Varanasi reveals that turmeric (Curcuma longa) has been cultivated, cooked, and utilized in Ayurvedic medicine in the Indian subcontinent for more than 4,000 years. Modern pharmacological studies confirm its primary polyphenol, curcumin, possesses potent systemic anti-inflammatory, antioxidant, and antimicrobial mechanisms.

1814Shampoo’s name comes from Hindi.

The word comes from the Hindi “chāmpo”, meaning to press or massage. Sake Dean Mahomed introduced head-massage “shampooing” baths in England in the early 1800s.