The Transit of Venus June 8, 2004 Presented By: Amber Foster, Brad Prather, and Dr. Summers

Discovery and History The first recorded transit of Venus was done by Jeremiah Horrocks and William Crabtree during the 1639 transit. Transits were the first way astronomers could accurately measure the distance from the Earth to the Sun. Today, Radar is used.

A planetary transit is much like a lunar eclipse. Venus will pass between the Earth and the Sun. The major difference is that the Moon appears to be about the same size of the Sun from Earth. Venus, on the other hand, appears very small from Earth.

Transits of Venus are only possible during early December and June when Venus’s orbital nodes pass across the Sun. Transits of Venus show a clear pattern of recurrence at intervals of 8 years, years, 8 years, and years. The 2004 transit will be best seen from Europe, Africa, and Asia. The final stages will be visible from the eastern United States and Canada.

Venus appears % of the Sun’s apparent diameter. The orbit of Venus is inclined 3.4 degrees with respect to Earth’s orbit. Between the Years 2000 BC to 4000 AD, a period of 6000 years, Venus will make a total of 81 transits. In comparison, Mercury makes 13 to 14 transits per century.

1631Dec Dec June June Dec Dec June June Dec Dec June June Dec Dec 10 TRANSITS OF VENUS

On June 8, 2004, Venus will cross the Sun’s disk at about 1:13am and will disappear at about 7:26am (Eastern Standard time). From Sunrise, that gives us approximately one hour of viewing.

Venus will move westward with respect to the Sun with an angular speed of 3.2 arc-minutes per hour. This means it will take about 6.2 hours for Venus to cross the Sun’s disk.

Position of Venus in relation to the Earth and Sun in 2020, 2012, 2004, and 1996.

The Transit of Venus is a rare occurrence that many will not want to miss; however, it is important to follow safety procedures when viewing this spectacular event. It is vital that viewers take precaution and protect their eyes at all times with the proper solar filters. No matter what protection is used, it is still important that one does not continuously stare at the sun. 1)Viewing with Protection: ** Do not make the careless mistake of wearing sunglasses to view the transit because they do not offer sufficient protection. However, inexpensive eclipse shades can be purchased to help aide in the viewing of the transit. They are equipped with special safety filters that seem similar to sunglasses, but these eclipse shades are much safer!

Telescopes with Solar Filters: ** The transit of Venus is best viewed with a telescope that contains a solar filter. ** The solar filter strengthens the magnification and it will clearly show the planet Venus and sunspots. Pinhole Projectors: ** This is an indirect way of viewing the sun and it is also a safe way to view the transit. The thing to remember about pinhole projectors is that they image displayed is upside down.

Safe Solar Viewing Continued: **Related Projection Methods: *** You can also use binoculars. The Exploratorium demonstrates the safe ways on *** Another safe way is with the tool called the sunspotter telescope. You can find one of these at *** There is also a way that a large crowd can view at one time. It is by using a sun gun. This can be found at

Other Links You may want to check out: 1) How to Observe the Sun Safely by Lee Macdonald 2) Observe and Understand the Sun, edited by Richard E. Hill 3) Safe Sunwatching Techniques from NASA’s spaceweather.com 4) Recomendaciones para Observar el Sor (Spanish version of safe sunwatching)

Venus