Science pictures

Greek authorities have appealed to swimmers to stay away from the beaches in the southern suburbs of Athens after thick black oil began washing up.

Winners and shortlisted images include a mosquito's foot and a skull-shaped tapeworm that latches onto the intestine of its host.

The 45-year-old Agia Zoni II sank while anchored off the coast of the island of Salamina (also known as Salamis), close to Greece's main port of Piraeus.

At least 91 people were killed by the massive earthquake that struck off the coast of southern Mexico on Thursday (7 September).

Irma's winds of around 175mph (290kph) tore down trees, and flattened homes, schools and hotels, destroying some of the world's most exclusive tourist resorts.

Hurricane Irma, one of the most powerful Atlantic storms in a century, is heading directly towards Florida after it lashed the Caribbean.

Smashed hotels, boats tossed into piles, and flooded streets and homes on Sint Maarten, the Dutch side of the Caribbean island of Saint Martin.

Harvey has dumped 15 trillion gallons (56 trillion litres) of rain on the Houston area, with another five trillion gallons to come.

The popular Italian tourist island of Ischia off the coast of Naples was hit by an earthquake, killing at least two people and injuring dozens.

Millions of Americans armed with protective glasses have staked out their positions for what should be the most observed and photographed eclipse in history.

Ten photos that brought about real change by influencing the way people think and swaying public and political opinion.

Around 400 bodies have been recovered so far, but the death toll is expected to rise as an estimated 500 are still missing.

In the middle of the Utah desert lies a US Army facility that tests chemical and biological weapons such as sarin and anthrax.

When the quake hit, the performers ran off the stage in terror and the audience thought the tremor was part of the show.

Fires in Indonesia, lit to clear forest and peatlands for plantations, cause an annual crisis that blankets large parts of southeast Asia in smog.

At least 53 people have lost their lives after parts of southeast Asia were inundated by flooding.

A heatwave is currently extending across the continent, with temperatures exceeding 40 degrees in some areas.

Mount Sinabung erupts again, spewing out a towering column of volcanic ash more than four kilometres (2.6 miles) high.

Yemen is suffering the worst cholera outbreak ever recorded in any country in the space of a single a year, but it has put off a vaccination campaign until 2018.

Fires have ravaged tinder-dry vegetation in France, Portugal, Italy, Spain, Croatia and Montenegro and across southern Europe.

More than ten villages in central Portugal have been evacuated as forest fires rage in the provinces of Castelo Branco and Santarem.

Four firefighters have been injured as wildfires rage along the French Riviera and on the Mediterranean island of Corsica.

Rescue authorities said a Swedish man and a Turkish man died in the collapse at the White Corner Club when the quake struck.

More than 2,200 firefighters on the ground and in the air have contained just seven percent of the Detwiler Fire.

The 2,000 residents of the town of Mariposa, in the Sierra Nevada mountains southwest of Yosemite, were ordered to flee as the Detwiler Fire approached.

The brains were preserved by heavy rains seeping into bullet holes in their skulls, turning them into a soap-like substance.

Photojournalist Danish Siddiqui follows the increasingly filthy river from its mountain source to the megacity of Kolkata.

Border collies Summer, Olivia and Das spend their days bounding through charred forests, unaware they're leaving a trail of seeds that could transform the landscape.

More than 1,000 firefighters and nine water-dropping aircraft are battling the blaze in Pedrogao Grande, which is raging for a third consecutive day.

Portugal's worst forest fires in living memory have so far claimed the lives of 62 people, most of whom died in their cars as they tried to flee the inferno.