A quick look at Transit of Venus facts and figures for June 5, 2012.
Transit Distances
Current Distance Earth to Sun = 150,000,000 km (1 au)
Current Distance Earth to Venus = 43,000,000 km (0.287 au)
Current Distance Venus to Sun = 107,000,000 km (0.713 au)
Size Comparison
Diameter of the Sun = 1,391,000 km
Diameter of Venus = 12,104 km
Diameter of Earth = 12,756 km
Local Transit Timeline (Northwest Territories)
Inuvik, Northwest Territories (68°N latitude)
Begins: 4:05 p.m. MDT
Ends: 10:49 p.m. MDT
Norman Wells, Northwest Territories (65°N latitude)
Begins: 4:05 p.m. MDT
Ends: 10:49 p.m. MDT
Yellowknife, Northwest Territories (62°N latitude)
Begins: 4:05 p.m. MDT
Ends: 10:49 p.m. MDT
Fort Smith, Northwest Territories (60°N latitude)
Begins: 4:05 p.m. MDT
Ends: Sunset at 10:43 p.m. MDT
Detailed Transit Timeline (Mountain Daylight Time)
Ingress Exterior: 4:05 p.m. MDT
Ingress Interior: 4:23 p.m. MDT
Transit Centre: 7:27 p.m. MDT
Egress Interior: 10:31 p.m. MDT
Egress Exterior: 10:49 p.m. MDT
Transit Path
Inuvik, Northwest Territories (68°N)
Yellowknife, Northwest Territories (62°N)
Fort Smith, Northwest Territories (60° N)
Frequently Asked Questions
What is a transit?
Transit is a term used to describe when one object passes in front of another object. When a planet, satellite, spacecraft, a plane, a bird or any other object passes in front of the Sun, it is a transit. Because the Sun is so bright, when something passes between the Earth and the Sun, it will appear as a dark silhouette against a bright yellow-orange circle.
How often do transits occur?
The inner planets Mercury and Venus pass between Earth and the Sun multiple times each year, however the perfect alignment needed for a planet to transit the Sun is very rare. Mercury transits are more common than Venus transits. Mercury will transit the solar disk approximately 13-14 times each century, while Venus will transit the Sun only twice (eight years apart) every one hundred years.
How much do we know about this rare planetary alignment?
Astronomers continue to study the complex nature of orbits and other factors that cause the Transit of Venus to be one of the rarest of predictable astronomical events. For reasons that are not fully understood, Venus transits tend to occur in pairs, eight years apart, and only in the months of June or December.
When will the Transit of Venus next be visible above the Northwest Territories?
The next Transit of Venus will occur in 2117, but it will not be visible above the Northwest Territories. The next time a Transit of Venus will be visible above the Northwest Territories will be eight years later, in 2125.
Why is the Transit of Venus important to scientists?
Scientists use the Transit of Venus to measure Earth’s distance to the Sun, which is approximately 150,000,000 kilometres, or 1 astronomical unit. An astronomical unit (AU) is an important because it is used to measure much larger distances, such as the diameter of the solar system (39.5 AU), the diameter of the Milky Way Galaxy (6,320,400,000 AU). The Astronomical Unit is also converted into light years to measure even greater distances (1 light year = 63,240 AU), such as the distance to the Andromeda Galaxy, which is 2.3 million light years away.
Scientists also use the Transit of Venus to examine the atmosphere of Venus, which consists of mostly carbon dioxide, with low levels of nitrogen and a layer of sulfuric acid clouds.
Also of scientific interest, the light displaced during a Transit of Venus can help scientists discover planets in orbit around other stars. These exo-planets (extra-solar planets) are too dim to be seen, but as they pass in front of a star (a transit) they block a tiny percentage of the star’s light. By analyzing these changes in the light of a star, scientists can confirm the presence of a planet, and in some cases can even estimate the size, temperature and atmosphere of the planet.
