FAQ

What is a transit of Venus?
The transit is the movement of Venus across the face of the sun as Venus orbits directly between Earth and the sun.
What can I expect to see?
You may safely view the transit of Venus only if you wear proper solar shades (not sunglasses); use a proper solar
filter over a telescope; or project a magnified image of the sun with a suitable indirect viewing technique.
Watch the black disk of Venus glide toward the edge of the sun after sunrise. A magnified view through a solar filter may reveal the “black drop” effect, sunspots, the atmosphere of Venus, and other rare sights.
What is the significance of a transit?
Transits help determine our place in the cosmos. In historic expeditions, explorers spanned the globe to time transits of Venus, from which they measured the size of the solar
system. Astronomers now seek earth-class planets
transiting distant stars.
How can I participate?
People of all ages can witness this rare phenomenon with proper viewing equipment. Students can time the transit and contribute their data to global observing projects to quantify the earth-sun distance.
Where is more info and resources?
www.transitofvenus.org
http://sunearth.gsfc.nasa.gov/sunearthday/

The “Black Drop” Effect:
At internal contact, Venus appears to elongate,
confounding astronomers for centuries.

Witness a celestial spectacle
not seen by any human now alive!

ransit of Venus

Venus passes between the sun and Earth.

Hands-on activities illustrate why transits of Venus are so rare.

NASA - Goddard Space Flight Center Scientific Visualization Studio

Observers must use proper solar filters, such as Eclipse Shades,
to watch the transit safely.

Explorers spanned the globe
to time the passage of Venus
across the sun.

June 8, 2004

Transit of Venus

Mishawaka, Indiana