The transit of Venus

BANGALORE: On June 6, Indians will have the privilege to witness the rare astronomical spectacle called ‘Transit of Venus’. This transit will be the last for this century and will be next visible only in 2117. The entire transit of Venus will be visible from Eastern Asia, Eastern Australia, North Western North America, the Arctic and North Pacific Ocean.The beginning of the event will not be visible from any place in India as the it will be in progress before sunrise. The end phase of the transit can be clearly seen from India.What is the transit? During a transit, Venus can be seen from Earth as a small black disk moving across the face of the Sun. The transit is similar to a solar eclipse by the Moon. While the diameter of Venus is almost four times that of the Moon, it appears smaller and travels more slowly across the face of the Sun because it is much farther away from Earth.Observations of transits of Venus has helped scientists use the principle of parallax to calculate the distance between the Sun and the Earth. The Transit of Venus deals with the eighteenth-century attempt to complete the Newtonian system of the world by determining its actual solar dimensions.     The 2004 transit of Venus was the first in 121 years. This was only the sixth transit of Venus since the telescope was invented. The last pair happened in 1874 and 1882.Observe caution:The safest way to observe a transit is to project the image of the Sun through a telescope, binoculars, or pinhole onto a screen. But the event can be viewed with the naked eye using filters specifically designed for this purpose. Visit the local planetarium.