Transit of Venus — last this century
A sight most people alive will never see again — the next transit comes in December 2117.
📍 Visible from where you are right now — computed in your browser
bearing · altitude · rise time · best time tonight
The moment of Transit of Venus — last this century: https://nowsky.org/e/venus-transit-2012 — opens at the right place and time, replayable, no login.
Available views: Orbit ✓ · Sky — (not visible in the sky)
The story
On 6 June 2012 Venus crossed the face of the Sun for the last time this century. The transit ran 6 hours 40 minutes, from 22:09 UT on the 5th to 04:49 on the 6th, and Korea saw it in full from 7:10 am to 1:50 pm — people with filters looked up at the Sun everywhere.
It was the partner of the 2004 transit, but its scientific weight was different. With the Kepler space telescope (launched 2009) finding exoplanets by the transit method, astronomers analysed sunlight filtered through Venus's atmosphere as a rehearsal, inside the solar system, for reading exoplanet atmospheres.
No transit had ever been observed with so many instruments. Hubble used the Moon as a mirror to analyse Venus's atmosphere in reflected light, and the Solar Dynamics Observatory recorded the whole event from space at very high resolution. That data is still the reference for interpreting the transit signals of Venus-like exoplanets.
The next transit of Venus is 11 December 2117 — for most people alive today this one was the first and the last. Observers then will dig through the 2012 data as historical record. Move the orbit view to 6 June 2012 to reproduce the Sun–Venus–Earth alignment.
Why it matters
The 2012 transit was the dress rehearsal for exoplanet atmospheric spectroscopy. Carbon dioxide was read from absorption lines in sunlight passing through Venus's atmosphere, and the same method led to James Webb's detection of WASP-39b's atmosphere in 2022 — the only real-world test available inside the solar system.
It also marked a peak of citizen participation. Tens of thousands joined the "Venus Transit" smartphone project to collect contact timings worldwide, reproducing Captain Cook's 1769 method by crowdsourcing.
Korea was among the rare regions to see the whole transit twice in a row, in 2004 and 2012. The observing events at schools and observatories became the base of a public-astronomy culture that carried on to the eclipses of 2017 and 2024.
How to watch
Move the orbit view to 6 June 2012, follow Earth and set the Sun as the gaze target, and Venus sits between them; placed beside 8 June 2004, the meaning of the eight-year pair becomes clear.
Select Venus in the sky view for its position and phase from your location. Move the time to the morning of 6 June 2012 and Venus is drawn over the Sun's disk; speed up the playback to watch the six-hour crossing.
The next transit is in 2117. Before that comes a transit of Mercury on 13 November 2032; Venus passes near the Sun in the late 2020s but does not cross the disk.
See this for yourself — replay the moment in the orbit view
Background
First contact came at 22:09 UT, so the Americas saw it on the evening of 5 June and Asia on the morning of the 6th. Europe caught only the final stages at sunrise, and South America and western Africa could not see it at all.
Aboard the International Space Station, astronaut Don Pettit photographed the transit through a solar filter he had brought for the purpose — the first transit of Venus photographed by a person in space.
The 2004–2012 pair were June transits; the next pair, 2117 and 2125, are December transits. Venus's orbital nodes fall in June and December, so transits happen only in those two months.
Korea held a special position for the 2012 transit. Only East Asia, eastern Australia and the western Pacific saw the whole event in daylight — all six hours and forty minutes from first contact at 7:10 am to last contact at 1:50 pm. Observatories and science centres across the country held solar-projection events, and the Gwacheon National Science Museum and regional observatories streamed it live. For Korean observers, who in 2004 had seen only the second half, 2012 was the first and last transit witnessed from start to finish.
FAQ
Was the whole transit visible from Korea?
Yes — from 7:10 am to 1:50 pm on 6 June 2012, start to finish.
Why does it matter for exoplanets?
Reading carbon dioxide from sunlight filtered through Venus's atmosphere validated the method used to analyse exoplanet atmospheres during transits.
When is the next one?
11 December 2117, followed by 8 December 2125.
How long did the transit last?
6 hours 40 minutes; Venus's silhouette, a thirtieth of the Sun's diameter, was visible to the naked eye through a filter.
Related
- Transit of Venus (2004)
- Transit of Mercury (2032)
- Venera 7 — landing on Venus
- Venus — object index
- The Sun — object index
Times and figures are approximate — verify with official sources when planning travel. Simulation uses J2000 mean elements.