LAST UPDATED Dec. 10: These dates are subject to change, and will be updated throughout the year as firmer dates arise. Please DO NOT schedule travel based on a date you see here. Launch dates collected from NASA, ESA, Roscosmos, Spaceflight Now and others.
Find out what's up in the night sky this month with our visible planets guide and skywatching forecast. Spot the International Space Station, Hubble Space Telescope and other satellites in the sky above with this satellite tracker.
Dec. 11: Russian cosmonauts Sergey Prokopyev and Oleg Kononenko will perform a 6-hour spacewalk outside the International Space Station to investigate the cause of a leak that was discovered in the Soyuz MS-09 spacecraft in August. [Watch Live]
Dec. 12/13: Rocket Lab will launch an Electron rocket from the Mahia Peninsula in New Zealand during a 4-hour launch window that opens at 11 p.m. EST on Dec. 12 (0400 GMT on Dec. 13). The rocket will deploy 10 cubesats for NASA's Venture Class Launch Services Program.
Dec. 13/14: The Geminid meteor shower peaks.
Dec. 16: Comet 46P/Wirtanen will make its closest approach to the sun, and it will be visible to the naked eye just after dusk.
Dec. 18: A SpaceX Falcon 9 rocket will launch the U.S. Air Force's first third-generation navigation satellite for the Global Positioning System (GPS 3-01) from Cape Canaveral Air Force Station in Florida at 9:24-9:50 a.m. EST (1424-1450 GMT).
Dec. 18: France's first Composante Spatiale Optique military reconnaissance satellite (CSO-1) will launch from the Guiana Space Center in Kourou, French Guiana on an Arianespace Soyuz rocket at 11:37 a.m. EST (1637 GMT).
Dec. 19: India will launch the GSAT 7A communications satellite for the Indian Air Force using a Geosynchronous Satellite Launch Vehicle Mk. 2.
Dec. 19/20: NASA astronaut Serena Auñón-Chancellor, European Space Agency astronaut Alexander Gerst and Russian cosmonaut Sergey Prokopyev are scheduled to undock their Soyuz MS-09 spacecraft from the International Space Station on Dec. 19 at 8:42 p.m. EST (0142 GMT on Dec. 20). They will land in Kazakhstan on Dec. 20 at 12:03 a.m. EST (0503 GMT).
Dec. 21: Winter solstice. Beginning at 5:09 p.m. EST (2209 GMT), it will officially be winter in the Northern Hemisphere and summer in the Southern Hemisphere. It will also be the shortest day of the year for the Northern Hemisphere and the longest day in the Southern Hemisphere.
Dec. 22: Full moon. The Cold Moon, also known as the Long Nights moon, will become full at 12:49 p.m. EST (1749 GMT).
Dec. 25: A Russian Proton rocket will launch the Blagovest No. 13L communications satellite from the Baikonur Cosmodrome in Kazakhstan at 5:12 p.m. EST (2212 GMT).
Dec. 26/27: A Russian Soyuz rocket will launch two Kanopus-V Earth observation satellites from the Vostochny Cosmodrome in Siberia at 9:07 p.m. EST on Dec. 26 (0207 GMT on Dec. 27).
Coming in 2019...
- Jan. 1: NASA's New Horizons spacecraft, which flew by Pluto in 2015, will reach its next target: Ultima Thule.
- Jan. 30: India will launch the Chandrayaan-2 mission to the moon.
- A SpaceX Falcon 9 rocket will launch the Crew Dragon spacecraft from Kennedy Space Center in Florida for an uncrewed test flight to the International Space Station. Liftoff is scheduled for no earlier than Jan. 17 at 8 p.m. EST (0100 GMT on Jan. 18).
- A United Launch Alliance Atlas V rocket will launch Boeing's first CST-100 Starliner spacecraft on an unpiloted Orbital Test Flight to the International Space Station. The capsule will dock with the space station, then return to Earth. (This test flight was delayed from August 2018 to mid-2019.)
- A SpaceX Falcon Heavy rocket will launch the Arabsat 6A communications satellite from Kennedy Space Center's historic Pad 39A.
- A SpaceX Falcon Heavy rocket will launch the U.S. Air Force's Space Test Program-2 mission from Kennedy Space Center in Florida.
- China will launch the Chang'e 5 mission to return samples from the moon. It will be the first lunar sample return mission attempted since 1976.
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