Many of us around the world will enjoy a firework display tonight (or have already); but what are the mechanisms behind the magnificent spectacle?



The story behind fireworks begins about 2000 years ago in China. Alchemists at the time were in search for an elixir which made them immortal. Obviously, they did not find this- what they did find however was a substance consisting of potassium nitrate, charcoal and suphur; or gunpowder,as we know it. The evolution of fireworks from gunpowder took another 1000 years until a monk named Li Tian realised that if you placed gunpowder into a bamboo tube and ignited it, an impressive explosion on sound and light ensued. Fireworks were born!

The gunpowder is responsible for the trajectory of the firework, ...

This is the pink-necked green pigeon (Treron vernans) and it is honestly not Photoshopped. They\'re found in Cambodia, Indonesia, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Vietnam. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical mangrove forests, and subtropical or tropical moist montane forests.

Mr. Peebles from Pekin, Illinois, USA was claimed as the world's smallest cat. Mr. Peebles is two years old cat weighing just three pounds and measuring 6.1 inches in height. This anomaly is caused by a genetic disorder.

A Hoopoe (pronounced who-poh, scientific name: Upupa epops) is a colourful African bird which has a distinctive ‘crown’ of feathers. The species is highly distinctive, with a long, thin tapering bill that is black with a fawn base. The strengthened musculature of the head allows the bill to be opened when probing inside the soil. The hoopoe has broad and rounded wings capable of strong flight; these are larger in the northern migratory subspecies. The Hoopoe has a characteristic undulating flight, which is like that of a giant butterfly, caused by the wings half closing at the end of each beat or short sequence of beats.

Listen to it sing:

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The kitti's hog-nosed bat (Craseonycteris thonglongyai), also known as the bumblebee bat is the smallest known species of mammal. Its natural habitat is in the countries of western Thailand and southeast Burma, where it occupies limestone caves along rivers. The bat is about 29 to 33 mm (1.1 to 1.3 in) in length and 2 g (0.071 oz) in mass, and is listed as a vulnerable species.

This is a butterfly gurnard fish. They have a large bony head and a bony rostrum on the snout with a very small median notch with tiny spines.  They are sandy with reddish bands and blotches and often turn red on capture.  The greenish pectoral fins are round with bright blue spots and margins, and a roundish black blotch with a bright blue margin and scattered blue spots inside.

If you were to guess, what do you think ancient humans used as contraceptives? It's definitely hard to list even a couple of ideas given how far we've come since the start of the 20th century. 

According to historians, the first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Dried dung was inserted into the vagina to form an impenetrable barrier. Other pessaries used back in the day included tree sap, lemon halves, cotton, wool, sea sponges, and elephant dung.

Later on, however, condoms made of animal bladders or intestines were also reportedly used. Luckily, in 1844, Charles Goodyear obtained the first patent for a rubber condom. ...

Nearly 20% of all electricity in the world comes from hydropower, and Norway has adapted to rely nearly entirely on it. They are the world leader in hydroelectricity production, generating 120 TWh annually. France and Sweden are next highest, each generating ~65 TWh per year.