A rainbow is an optical phenomenon that can occur under certain meteorological conditions. It is caused by refraction, internal reflection and dispersion of light in water droplets resulting in a continuous spectrum of light appearing in the sky. The rainbow takes the form of a multicoloured circular arc. Although a rainbow spans a continuous spectrum of colours, it is traditionally assigned a discrete sequence, with red, orange, yellow, green, blue, indigo and violet as the most common list. The rainbow inspired the rainbow flag, a symbol of LGBT pride and Pride Month. This portion of a rainbow, appearing to rise from a lakeside forest, was photographed in 2005 in Jasper National Park in Alberta, Canada.

Photograph credit: Wing-Chi Poon

The western bowerbird (Chlamydera guttata) is a species of bird in the family Ptilonorhynchidae. The species is endemic to Australia, where it has a disjunct distribution, occurring in both Central Australia and the Pilbara region of Western Australia. It is 24 to 28 centimetres (9.4 to 11.0 in) in length with a mass of 120 to 150 grams (4.2 to 5.3 oz). The plumage is brown with reddish or buff spots over the throat, chest, neck, back head and wings, with a pink erectile crest on the nape. Its tail is brown, with the undersides buff. Males and females are similar in appearance, except that the tail of the female is slightly longer and it is more spotted on the throat than the male. This western bowerbird was photographed near Alice Springs in the Northern Territory in 2022.

Photograph credit: John Harrison

NGC 6530 is a young open cluster of stars lying around 4,350 light years from Earth in the constellation Sagittarius. The cluster is set within the larger Lagoon Nebula, a large interstellar cloud of gas and dust. This photograph of a portion of NGC 6530 was taken by NASA's Hubble Space Telescope released in 2022, with the Lagoon Nebula giving the image its smoky appearance.

Photograph credit: ESA / Hubble / NASA / O. De Marco

Key Monastery is a monastery belonging to the Gelugpa school of Tibetan Buddhism, located at an elevation of 4,166 m (13,668 ft) on a hill rising above the Spiti valley in the northern Indian state of Himachal Pradesh. Said to have been founded in the 11th century, it is the largest monastery in Spiti, housing hundreds of monks. This view shows the monastery in winter, overlooking the snow-covered Spiti river valley with the Himalayas in the background.

Photograph credit: Kulbhushan Suryawanshi

Clara McAdow (1838–1896) was an American women's suffragist and mine owner. Born in Ohio, she grew up in Jackson, Michigan, relocating to Montana with her first husband, C. E. Tomlinson. When Tomlinson died, she took their savings and invested in real estate in Billings. Through her real-estate ventures, she met her second husband, Perry McAdow. She purchased from him the Spotted Horse mine, which he had received as payment for a debt. Clara took charge of all aspects of the mine, directing all of its operations and often living on site. McAdow was intensely interested in the women's suffrage movement, hosting Carrie Chapman Catt and Susan B. Anthony in her home to promote giving women the vote.

Photograph credit: unknown; restored by Adam Cuerden

The Interior of the Palm House on the Pfaueninsel Near Potsdam is the title of two oil-on-canvas paintings by Carl Blechen, completed between 1832 and 1834. Both depict four odalisques as they relax in a palm house (which was destroyed by fire in 1880) at the royal retreat of Pfaueninsel near Berlin, but have different angles of view and compositions. The works were commissioned by King Frederick William III of Prussia and are now in the Hamburger Kunsthalle and the Art Institute of Chicago, with an 1832 color study for the work found in the Alte Nationalgalerie in Berlin. This picture shows the Chicago version of the painting, which was gifted by Frederick William to his daughter Alexandra Feodorovna, the wife of Emperor Nicholas I of Russia. It remained in the Russian imperial collection until around 1917, became part of a Swiss collection around 1920, and was owned by private collectors prior to its purchase by the Art Institute of Chicago in 1996.

Painting credit: Carl Blechen

Tenthredo scrophulariae, the figwort sawfly, is a species of insect in the family Tenthredinidae, found across Europe. The larvae are relatively large, with a length of 30 millimetres (1.2 in) and having 22 legs. They have a white body with black spots, and feed on mullein and figworts. They feed from August to September and emerge as adults in May the following year. This T. scrophulariae larva was photographed near Keila in north-western Estonia.

Photograph credit: Ivar Leidus

Ruddigore is a comic opera in two acts, with music by Arthur Sullivan and a libretto by W. S. Gilbert. It is one of the Savoy operas and the tenth of fourteen comic operas written together by Gilbert and Sullivan, and was first performed by the D'Oyly Carte Opera Company at the Savoy Theatre in London on 22 January 1887. The first night was not altogether a success, as critics and the audience felt that Ruddygore (as it was originally spelled) did not measure up to its predecessor, The Mikado. However, after it was revived by D'Oyly Carte in 1920, the work was reassessed more positively. This illustration was created by the British illustrator H. M. Brock for the 1921 revival of Ruddigore at the Prince's Theatre in London. Published in the October 29 issue of The Sphere, it depicts a scene from the opera in which the ghosts of Sir Ruthven Murgatroyd's ancestors step out of their picture frames and accuse him of not having committed a crime every day in accordance with the family curse.

Poster credit: H. M. Brock; restored by Adam Cuerden

Girvan Yuddha Bikram Shah (1797–1816) was the fourth king of Nepal, ruling from 1799 to 1816. This drawing of the king was produced by an unknown artist around 1815 with opaque watercolor and gold on paper, and is now in the collection of the Los Angeles County Museum of Art.

Illustration credit: unknown; restored by Captain Medusa

Dubrovnik, historically known as Ragusa, is a city in southern Dalmatia, Croatia, by the Adriatic Sea. A seaport and the centre of the Dubrovnik-Neretva County, it is one of the most prominent tourist destinations in the Mediterranean. Its total population is 41,562 as of the 2021 census. In 1979, the centre of the city was added to UNESCO's list of World Heritage Sites in recognition of its outstanding medieval architecture and fortified old town. This aerial panorama of Dubrovnik was taken in 2016.

Photograph credit: Chensiyuan; edited by Bammesk

The 1974 aluminum cent was a one-cent coin proposed by the United States Mint in 1973. Composed of an alloy of aluminum and trace metals, it was intended to replace the predominantly copper–zinc cent due to the rising costs of coin production in the traditional bronze alloy. None of the 1,571,167 coins struck were released into circulation. The coin depicted here was donated to the National Numismatic Collection at the Smithsonian Institution's National Museum of American History.

Coin design credit: Victor David Brenner and Frank Gasparro; imaged by the National Numismatic Collection