No man who witnessed the Venus transit in 2004 had seen the previous transit in 1882, and a lot had happened since then: Twelve astronauts had walked on the Moon, unmanned probes had visited distant corners in our Solar System and big observatories were scanning the Universe.
by Anne Mette Sannes
During the transit: The atmosphere of Venus was seen as a bright arc outside the solar disk. The picture was taken with the one-meter telescope at La Palma. Due to the sharp picture and fine details on the solar surface, the atmosphere of Venus could also be seen while Venus was crossing the solar disk.
Photo: Swedish Solar Telescope/Institute for Solar Physics
2004 A Venus transit for the people!
Since about 1950, the astronomers had learned to recognize Venus as a deserted place with extreme greenhouse effect, temperatures around 470 C and with an atmosphere consisting of carbon dioxide and sulfuric acid not exactly a place to look for life. Also, big telescopes had revealed the planets rotation period 243 days the longest rotation period of all the planets in the Solar System, and also discovered that the planet has a retrograde rotation it spins the opposite way!
In 1962, the unmanned spacecraft Mariner 2 passed Venus, followed by Venera 7 in 1970 which also landed on the planets surface. In 1990, Magellan went into orbit around Venus and mapped the surface by radar instruments which penetrated the planets thick atmosphere.
Of all the rocky planets, our sister planet turned out to be the least earth-like. What new was there to learn from the 2004-transit? Thanks to the radar and laser technology, the distances in the Solar System have, since the last transit, been determined with great accuracy. The distance Earth Sun is calculated to the nearest inch and the distances between planets to the nearest mile.
But still, the Venus transit in 2004 was a transit for the people. Far better pictures were taken and schools across the world measured the distances in the Solar System.
June 6th is a new Venus transit. For all of us, this will be the last transit in our lives unless one stays alive for another 105 years.
Read more about the Venus transit in 2012
Major celestial events in Norway 2010-2015