September 24 belongs to Hana Bru

On September 24, 1996, 71 countries signed at the UN the Comprehensive Nuclear-Test-Ban Treaty (CTBT), prohibiting any nuclear explosion for military or civilian purposes. Although it has not formally entered into force — since several nuclear-armed countries have not ratified it — its signing is considered one of the greatest achievements of international disarmament.

On September 25, 1992, NASA launched Mars Observer, its first mission to Mars in seventeen years. The probe was meant to map the planet from orbit, but contact was lost three days before orbital insertion in August 1993. The loss of the probe cost nearly one billion dollars and delayed Martian exploration by several years.

On September 24, 1973, Guinea-Bissau proclaimed its independence from Portugal during a long liberation war that had begun in 1963. Portugal did not officially recognise it until 1974, after the Carnation Revolution in Lisbon. The country, one of the smallest in mainland Africa, remains one of the poorest in the world today.