|Centuries:||20th century – 21st century – 22nd century|
|Decades:||2010s 2020s 2030s – 2040s – 2050s 2060s 2070s|
|Years:||2037 2038 2039 – 2040 – 2041 2042 2043|
|Ab urbe condita||2793|
|British Regnal year||N/A|
|Chinese calendar||己未年 (Earth Goat)
4736 or 4676
— to —
庚申年 (Metal Monkey)
4737 or 4677
|- Vikram Samvat||2096–2097|
|- Shaka Samvat||1962–1963|
|- Kali Yuga||5141–5142|
|Japanese calendar||Heisei 52
|Julian calendar||Gregorian minus 13 days|
|Minguo calendar||ROC 129
|Thai solar calendar||2583|
2040 (MMXL) will be a leap year starting on Sunday (link displays the full calendar) of the Gregorian calendar (dominical letter AG), the 2040th year of the Common Era (CE) and Anno Domini (AD) designations, the 40th year of the 3rd millennium, the 40th year of the 21st century, and the 1st year of the 2040s decade.
Predicted and scheduled events
- May 11 – Partial solar eclipse.
- September 8 – Planetary alignment of Mercury, Venus, Mars, Jupiter, Saturn and the crescent Moon.
- November 4 – Partial solar eclipse.
- Global energy consumption will have increased by 56 percent from 2010, from 524 quadrillion British thermal units (Btu) to 820 quadrillion Btu.
- Japan will have shut down the last of its nuclear power plants.
- The Antarctic treaty will come under review.
- The United States Air Force will start an at least partial phase-out of their B-52 Bombers, which by 2040 will have served 85 years of combat.
- NASA predicts that by this year it will cost only tens of dollars per pound to launch humans or cargo into space.
- Projected completion date for the Trans-European Transport Networks (TEN-T) rail corridor running from Germany to southern Italy.
- Space-based solar power will be commercially viable.
- The Great Red Spot on Jupiter's atmosphere will become circular according to calculations based on its reduction rate at present.
- Amsterdam aims to be fossil fuel free - powering its electric cars, trucks, boats, and buildings with energy generated by wind, solar, and biomass. (Think Progress)
- Completion of the Northeast Corridor high-speed rail route, running from Boston to Washington DC.
- Pollen counts will be more than double today's level, due to climate change.
- The anime series Macross Plus, Cybuster, and Bubblegum Crisis Tokyo 2040 are all set in this year.
- In the universe of Star Trek: The Next Generation, the television becomes obsolete.
- The Doctor Who short story collection Short Trips: 2040 is set in the year 2040.
- The events of BBC science-fiction drama Outcasts take place primarily in this year.
- Phantom 2040 television series and comic strips take place during this year.
- Edward de Bono's film 2040: Possibilities by Edward de Bono presents an idea, in the form of a lecture, what 2040 might be like.
- In JLU, the episode The Once and Future Thing Pt. 2 Time Warped takes place in an alternate 2040 where Batman Beyond, Warhawk, Static, and Bruce Wayne are the only remaining members of the JLU. (2005)
- In Static Shock, the episode Future Shock takes place primarily in this year with young Static being transported to the future where he teams up with Terry/Batman to help save old Static from the Kobras. (2004)
- "JSC Celebrates 40 Years of Human Space Flight". NASA. 2002-09-03. Retrieved 2010-01-06.
- Jim Baumann. "Development of Alpine Rail Link using GIS". Retrieved 2011-12-31.
- Nancy Owano (2011-11-15). "IAA says 'Yes We Can' to power plants in orbit". Physorg.com. Retrieved 2011-12-31.
- "The Year 2040: Double the Pollen, Double the Allergy Suffering?". NewsWise/American College of Allergy, Asthma and Immunology (ACAAI). 30 October 2012. Retrieved 8 August 2013.
- "No More TV in 2040?". StarTrek.com. 2002-07-24. Retrieved 2011-12-21.