The secretive indri (Indri indri) of Madagascar, the largest living lemur. It is also critically endangered and highly evolutionarily distinct with no close relatives, which makes its branch one of most precarious on the mammal evolutionary tree. In the likely event that the indri goes extinct, we will lose 19m years of unique evolutionary history from the mammal tree of life. (Photo by Pierre-Yves Babelon/Aarhus University)

British fashion model Twiggy plays around on the bumper cars at the Bertram Mills Circus in London, England on January 10, 1967. (Photo by AP Photo)

In this June 1, 2016 photo, Maria Arias stands near her kitchen as she puts on earrings while getting ready for school in Caracas, Venezuela. So many students have fainted from hunger at Maria's school that administrators told parents to keep their children home until they could find more food. (Photo by Ariana Cubillos/AP Photo)

Soldiers of People's Liberation Army (PLA) Lanzhou Military Region jump through a burning obstacle during a training session at a military base in Tianshui, Gansu province, China, January 6, 2016. (Photo by Reuters/Stringer)

The Royal Observatory just announced its Astronomy Photographer Of The Year 2013 winners. Australian photographer Mark Gee was chosen among a thousand amateur and professional photographers around the globe to win the top title. His work is part of an exhibition of the winning photographers, which opened on Sept. 19 at the Royal Observatory Greenwich. The Royal Observatory shared with us the winners and notable mentions of the competition. Their descriptions of the prizewinners can be found below the images.

Maasai men of Matapato jostle to parade as they attend the Olng'esherr (meat-eating) passage ceremony to unite two age-sets; the older Ilpaamu and the younger Ilaitete into senior elderhood as the final rite of passage, in Maparasha hills of Kajiado, Kenya on September 23, 2020. Thousands of Maasai men clad in red and purple shawls and with their heads coated in red ochre gathered this week for a ceremony that transforms them from Moran (warriors) to Mzee (elders). (Photo by Thomas Mukoya/Reuters)

Since Rodrigo Duterte became president last year, his brutal campaign against drugs has claimed thousands of lives. Human rights groups say he is guilty of crimes against humanity, yet that is scant comfort to those mourning loved ones. Here: Constantino de Juan’s seven children sit on a sofa that still bears the bullet hole from their father’s shooting. Juan was preparing a spaghetti dinner on his daughter’s birthday when he was killed. (Photo by James Whitlow Delano/Funded by the Pulitzer Center on Crisis Reporting/The Guardian)