Harvard Two Harvard scientists report, in the peer-reviewed journal "Science", the first creation of metallic hydrogen in a laboratory, using a diamond anvil cell. Other researchers did not agree with this finding when it was first posted on the arXiv preprint server in October 2016, and have not yet changed their positions.
Trump administration Vice President Mike Pence gives a speech at the March for Life promising to end the tax-payer status of abortion providers.
President Trump signs an executive order limiting refugees and immigration from seven Muslim-majority countries, including Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen. The order also prioritizes the vetting of Christian refugees of the Syrian Civil War.
California independence referendum Yes California, the campaign to reinstate the independence of California launches its signature campaign.
Cameroon Protests take place in Cameroon following the arrest of several opposition leaders and internet services being cut off in the nation's English-speaking areas.
North Korea and weapons of mass destruction New satellite imagery released by think tank 38 North indicates North Korea has resumed operations at its Yongbyon Nuclear Scientific Research Center in North Pyongan Province.
Israeli–Palestinian conflict Israeli authorities approve 153 construction permits for settlement homes in East Jerusalem, and plan to approve another 11,000 in the coming months.
United Kingdom–United States relations British Prime Minister Theresa May meets with U.S. President Donald Trump at the White House in Washington, D.C.. This is the first visit by a foreign leader since Trump's inauguration last Friday.
Santa Olga A wildfire destroys almost the entire town of Santa Olga in Chile's central Maule Region as a Russian firefighting Ilyushin Il-76 arrives to help fight the worst wildfire in Chile's modern history.
Wet Seal The clothing retailer Wet Seal announces the closing of all 148 of its brick-and-mortar stores after filing for bankruptcy in 2015. The news comes on the heels of recent announcements of the closings of other major clothing chains, such as The Limited.
Somali Civil War (2009–present) Al-Shabaab militants attack a remote AMISOM base in southern Somalia, claiming to have killed dozens of Kenyan troops.