Transit of Venus: A Rare Astronomical Event

A transit of Venus happens when Venus passes directly between Earth and the Sun.
Venus appears as a small black dot moving slowly across the Sun’s face.
These events are extremely rare, occurring in pairs eight years apart, separated by over a century.
The last pair occurred in 2004 and 2012; the next won’t happen until 2117 and 2125.
Early astronomers used Venus transits to calculate the astronomical unit—the Earth-Sun distance.
Observing safely requires solar filters, as with solar eclipses and Mercury transits.
The transit can last up to 7 hours, depending on viewing location.
Historical expeditions sent scientists worldwide to record the exact timing.
The phenomenon inspired global cooperation in astronomy as early as the 18th century.
Transits of Venus are among the most celebrated and scientifically important celestial events in history.