Stars are pictured over the famous Matterhorn mountain, seen from the Riffelberg area, in Zermatt, Switzerland.

Jean-Christophe Bott/Keystone/AP

Stars seen in the sky over the Matterhorn mountain, seen from the Riffelberg area, in Zermatt, Switzerland

A Bangladeshi child watches from behind soldiers of Bangladeshi Rapid Action Battalion a rally to celebrate the first day of the Bangla New Year in Dhaka, Bangladesh, Tuesday, April 14, 2015.

A.M. Ahad/AP

A child watches a rally to celebrate the first day of the Bangla New Year in Dhaka, Bangladesh, from behind soldiers of the Bangladeshi Rapid Action Battalion

People wearing costumes attend the annual water-splashing festival to mark the New Year of the Dai minority in Jinghong, Yunnan province.

China Daily/Reuters

People wearing costumes attend the annual water-splashing festival to mark the New Year of the Dai minority in Jinghong, Yunnan province, China

A young Yemeni poses with a gun during a protest against Saudi-led airstrikes on Yemen, outside the Sana a-based UN offices in Sana a, Yemen, 13 April 2015. According to reports, Yemeni students rallied outside the Sana a-based UN offices, calling for an end of the Saudi-led military Decisive Storm operation, accusing the Saudi-led coalition of attacking schools and civilian houses throughout Yemen in their bid the degrade the capabilities of the Houthis and their allies.

Yahya Arhab/EPA

A young Yemeni poses with a gun during a protest against Saudi-led airstrikes on Yemen, outside the Sanaa based UN offices in Sanaa, Yemen on Monday

Revellers use water guns as they participate in a water fight during Songkran Festival celebrations at Silom road in Bangkok April 13, 2015. The Songkran festival, also known as the water festival, marks the start of Thailand's traditional New Year and is believed to wash away bad luck

Athit Perawongmetha/Reuters

Revellers take part in a water fight during Songkran festival celebrations at Silom road in Bangkok on Monday. The Songkran festival, also known as the water festival, marks the start of Thailand’s traditional New Year and is believed to wash away bad luck.

A Bulgarian Orthodox priest leads an annual religious march marking the second day of Easter at the Bachkovo monastery on on April 13, 2015.

Nikolay Doychinov/AFP

An Orthodox priest leads an annual religious march marking the second day of Easter at the Bachkovo monastery in Bulgaria on Monday.

A woman does acrobatics as she waits for a band to start playing at the Coachella Valley Music and Arts Festival in Indio, California

Lucy Nicholson/Reuters

A woman does acrobatics as she waits for a band to start playing at the Coachella Valley Music and Arts Festival in Indio, California.

The sun rises off the North East coast near Cullercoats bay in North Tyneside, as Britain is set to bask in its hottest temperatures of the year so far, with the mercury expected to soar higher than in parts of Spain this week.

Owen Humphreys/PA

The sun rises off the northeast coast near Cullercoats Bay in North Tyneside, as Britain is set to bask in its hottest temperatures of the year.

German Chancellor Merkel and Indian Prime Minister Modi look at a UMI robotic arm at the world's largest industrial technology fair, the Hannover Messe, in Hanover...German Chancellor Angela Merkel and Indian Prime Minister Narendra Modi (R) look at a UMI robotic arm at the world's largest industrial technology fair, the Hannover Messe, in Hanover April 13, 2015.

Wolfgang Rattay/Reuters

German Chancellor Angela Merkel and Indian Prime Minister Narendra Modi look at a UMI robotic arm at the world’s largest industrial technology fair, the Hannover Messe, in Hanover.

A member of the Sudanese security forces waits outside a polling station where he is registered to vote, in Khartoum, Sudan, Monday, April 13, 2015.

Mosa'ab Elshamy/AP

A member of the Sudanese security forces waits outside a polling station, where he is registered to vote, in Khartoum, Sudan on Monday.

German Chancellor Angela Merkel and Greek Prime Minister Alexis Tsipras listen to their countries' national anthems upon his arrival for talks at the Chancellery on March 23, 2015 in Berlin, Germany. The two leaders are meeting as relations between the Tsipras government and Germany have soured amidst contrary views between the two countries on how Greece can best work itself out of its current economic morass.

Sean Gallup/Getty Images

German Chancellor Angela Merkel and Greek Prime Minister Alexis Tsipras listen to their countries’ national anthems upon his arrival for talks at the Chancellery on Monday in Berlin, Germany

An Iraqi Shiite fighter from the Popular Mobilisation units, part of the Zahraa Brigade, poses for a picture under a sign which reads in Arabic "Lions of Najaf" during a training exercise in the central Iraqi city of Kufa, some 160 kms south of Baghdad, on March 23, 2015.

Haidar Hamdani/AFP

An Iraqi Shia fighter from the Popular Mobilisation units, part of the Zahraa Brigade, poses for a picture under a sign which reads in Arabic “Lions of Najaf” during a training exercise in the central Iraqi city of Kufa, some 160 kms south of Baghdad, on Monday

A cosplayer poses for a portrait at the cosplay area during the Anime Japan 2015 Expo in Tokyo, Japan. Cosplay (Costume play) is a subculture that sees participants role play as a specific character of their choice. Many of the popular characters are sourced from manga, anime, comic books, video games and cartoons, often the cosplayer will take on the body language, clothing and mannerisms of the character. AnimeJapan 2015, is one of the largest anime festivals in Japan, offering visitors entertainment such as stage performances, screenings, workshops, cosplaying areas, and a chance to buy exclusive anime themed goods

Chris McGrath/Getty Images

A cosplayer poses for a portrait at the cosplay area during the Anime Japan 2015 Expo in Tokyo, Japan. Cosplay (Costume play) is a subculture that sees participants role play as a specific character of their choice. Many of the popular characters are sourced from manga, anime, comic books, video games and cartoons, often the cosplayer will take on the body language, clothing and mannerisms of the character

A Syrian woman carries water with her children in a refugee camp in Suruc, in the province of Sanliurfa, Turkey. Turkey has one of the largest populations of Syrian refugees fleeing the ongoing civil war with official estimates currently at 1.6 million. Border towns such as Suruc have received a large number of refugees though other refugees have settled as far afield as Istanbul

Carl Court/Getty Images

A Syrian woman carries water with her children in a refugee camp in Suruc, in the province of Sanliurfa, Turkey

An Indian farmer herds his sheep on the dry bed of a river at Bibi Nagar in Nalgonda District, some 40 kilometers from Hyderabad on March 23, 2015.

Noah Seelam/AFP

An Indian farmer herds his sheep on the dry bed of a river at Bibi Nagar in Nalgonda District, some 40 kilometers from Hyderabad on Monday

The People's Liberation Army's Air Force Air Demonstration Team, China's best-known aerobatic team, performs at Langkawi International Maritime and Aerospace Exhibition in Langkawi, Malaysia, on Thursday

Vincent Thian/AP

The People’s Liberation Army’s Air Force Air Demonstration Team, China’s best-known aerobatic team, performs at Langkawi International Maritime and Aerospace Exhibition in Langkawi, Malaysia, on Thursday

A father and son on a makeshift boat made from styrofoam paddle through a garbage filled river as they collect plastic bottles that they can sell in junkshops in Manila on March 19, 2015. They earn three US dollars a day. The Philippines will be observing World Water day on March 22, a global event that focuses on finding access to clean and safe water

Noel Celis/AFP

A father and son on a makeshift boat made from styrofoam paddle through a garbage filled river as they collect plastic bottles that they can sell in junkshops in Manila on Thursday

Police officers are seen on the pavement outside parliament in Tunis...Police officers are seen on the pavement outside parliament in Tunis March 18, 2015. Gunmen attacked Tunisia's national museum near its parliament on Wednesday, killing at least seven tourists and taking others hostage inside the building, the government said

Zoubeir Souissi/Reuters

Police officers are seen on the pavement outside parliament in Tunis. Gunmen attacked Tunisia’s national museum near its parliament on Wednesday, killing at least seven tourists and taking others hostage inside the building

Israeli Prime Minister Benjamin Netanyahu waves to supporters at the party headquarters in Tel Aviv March 18, 2015. Netanyahu claimed victory in Israel's election after exit polls showed he had erased his center-left rivals' lead with a hard rightward shift in which he abandoned a commitment to negotiate a Palestinian state

Amir Cohen/Reuters

Israeli Prime Minister Benjamin Netanyahu waves to supporters at the party headquarters in Tel Aviv on Wednesday. Netanyahu claimed victory in Israel’s election after exit polls showed he had erased his center-left rivals’ lead with a hard rightward shift in which he abandoned a commitment to negotiate a Palestinian state

Wheelchair-bound Palestinian student teacher Ahmed al-Sawaferi, 25, who said that he lost his both legs and his left arm in an Israeli air strike in 2008, gives a class at an elementary school in Gaza City...Wheelchair-bound Palestinian student teacher Ahmed al-Sawaferi, 25, who said that he lost his both legs and his left arm in an Israeli air strike in 2008, gives a class at an elementary school in Gaza City March 18, 2015. Al-Sawaferi, a father for two children, is due to hold a B.A in Islamic studies after finishing his last university semester in June this year

Suhaib Salem/Reuters

Wheelchair-bound Palestinian student teacher Ahmed al-Sawaferi, 25, who said that he lost his both legs and his left arm in an Israeli air strike in 2008, gives a class at an elementary school in Gaza City on Wednesday. Al-Sawaferi, a father for two children, is due to hold a B.A in Islamic studies after finishing his last university semester in June this year