1999 in science

The year 1999 in science and technology included many events, including those below.

Aeronautics

February 27 – While trying to circumnavigate the world in a hot air balloon, Colin Prescot and Andy Elson set a new endurance record after being in a hot air balloon for 233 hours and 55 minutes.
March 3 – Bertrand Piccard and Brian Jones begin their attempt to circumnavigate the world in a hot air balloon without stopping. Their journey ended in success on March 20.

February 7 – Stardust is launced on a mission to collect samples of a comet coma, and return them to Earth.
July 20 – Mercury program: Liberty Bell 7 is raised from the Atlantic Ocean.
July 31 – NASA intentionally crashes the Lunar Prospector spacecraft into the Moon, thus ending its mission to detect frozen water on the moon's surface.
NASA loses two Mars probes, the Mars Climate Orbiter and the Mars Polar Lander.
The Subaru 8.3-m and Gemini North 8.1-m reflecting telescopes open at the Mauna Kea Observatory in Hawaii.

The bacterium Thiomargarita namibiensis is discovered off the coast of Namibia. At 0.3mm in diameter, it is largest bacteria yet discovered.

March 26 – The Melissa worm attacks the Internet.
First working 3-qubit NMR computer demonstrated at IBM's Almaden Research Center. First execution of Grover's algorithm.

January 25 – A 6.0 Richter scale earthquake hits western Colombia, killing at least 1,000.
August 17 – A 7.4-magnitude earthquake strikes northwestern Turkey, killing more than 17,000 and injuring 44,000.