EarthSky // Tonight // Astronomy Essentials Bruce McClure Jun 05, 2012

Everything you need to know: Venus transit on June 5-6

Venus appeared as a small dark dot crossing sun’s face for last time this century on June 5-6, 2012. Last transit of Venus in our lifetimes! Transit times and more here.

June 2012 guide to the five visible planets

Venus’ transit day has passed – the last transit of Venus for the 21st century! The brightest planet, Venus, passed right in front of the sun for nearly seven hours on June 5-6, 2012, but, from many places, the transit was in progress at sunrise or sunset. During the transit, Venus appeared in silhouette as a small, dark dot moving in front of the solar disk. This exceedingly rare astronomical event – a transit of Venus – won’t happen again until December 11, 2117. However, a transit of Mercury will take place on May 9, 2016.

Gallery: Venus transit June 5-6, 2012

As with any solar eclipse, you must have proper eye protection to view a planet transiting across the sun. Click on the following link to hear why eclipses glasses and welder’s glass might not be best for viewing a solar eclipse, to learn how to make an indirect viewing system, and to find a webcast: What’s the best way to view the June 5-6 transit of Venus safely?

Transit of Venus June 8, 2004. Image Credit: Wikimedia Commons

Who saw the June 5-6, 2012 transit of Venus?

Depending on where you live worldwide, the transit of Venus happened on June 5 or 6, 2012. If you live in the world’s Western Hemisphere (North America, northwestern South America, Hawaii, Greenland or Iceland), the transit started in the afternoon hours on June 5. In the world’s Eastern Hemisphere (Europe, Africa, Asia, Australia or New Zealand), the transit was first seen at sunrise or in the morning hours on June 6.

Map of where June 5-6, 2012 Venus transit will be seen. Image Credit: Michael Zeiler, eclipse-maps.com

Click here to expand image above

Click here to expand chart above

Transit Computer giving the Universal Time for your sky

The chart above shows the times of the 2012 transit of Venus in Universal Time (essentially the same as UTC). To know when any astronomical event occurs in your part of the world, you need to translate the times to your time zone. Here’s how to do that: How do I translate Universal Time into my time?

Be careful and watch for the time of sunset or sunrise in your location. In the continental United States, for example, the greatest transit took place just before sunset for most of us. During last month’s solar eclipse, which was also at sunset for U.S. locations, many people told us they missed out because their viewing location was hindered by trees or tall buildings. Don’t let that happen to you! If you’re in the continental U.S., be sure to find a viewing location with a clear view of the horizon. To know the time of sunset or sunrise for your location, try this site, which will let you create a custom sunrise/sunset calendar: Sunrise/sunset times for your sky

From the mainland U.S., the West Coast saw more hours of the transit than the East Coast did. Here in Austin, Texas, we got to see the first half of the transit, but the second half took place after sunset – or when the sun was beneath our horizon.

In the world’s Eastern Hemisphere, it was as equally important to find a level eastern horizon on June 6. For Africa, Europe, much of Asia and western Australia, the sun rose (on June 6) as the transit was taking place. Elsewhere in the Eastern Hemisphere, the transit started in the morning hours on June 6.

More great links on 2012 transit of Venus

Click here to find out if an observatory or astronomy club near you is giving a public presentation.

What’s the best way to view the June 5-6 transit of Venus safely?

View from space: Venus edging closer to sun prior to transit!

Tony Misch and William Sheehan: Video of 1882 Venus transit

Deborah Byrd and Jorge Salazar talk about the transit on this week’s EarthSky 22

ISS astronaut first man in space to photograph a Venus transit

Venus goes from east to west (left to right) across the solar disk

Image credit: Fred Espenak

Contact I: ingress exterior – Venus’ first contact with sun’s exterior
Contact II: ingress interior – Venus first seen totally within solar disk
Greatest transit: transit center – center of transit
Contact III: egress interior – Venus last seen totally within solar disk
Contact IV: egress exterior – Venus’ last contact with sun’s exterior

The contact times (I, II, greatest transit, III and IV) on the above illustration are given in Universal Time. It is important to note that these times are for an imaginary observer at the Earth’s center – not the Earth’s surface. So if you translate from Universal Time to the clock time in your time zone, it’ll give you a ballpark reference of your local transit times, which won’t be off by any more than a maximum of plus or minus seven minutes.

Why is a transit of Venus so rare?

The last transit of Venus was June 8, 2004. But don’t be fooled by that proximity in time. Transits of Venus are very rare, plus transits tend to occur in pairs. They occur in a pattern that repeats every 243 years, with pairs of transits eight years apart separated by long gaps of up to 121.5 years. Before 2004, the last pair of transits were in December 1874 and December 1882.

Venus, the second planet outward from the sun and next planet inward from Earth, swings between the Earth and sun (at a point called inferior conjunction) five times every eight years, or one time in every 584 or so days. (See the Diagram of Venus’ orbit around the sun below.) More often than not, Venus passes above or below the solar disk at inferior conjunction – that point in its orbit where Venus passes out Earth’s evening sky and into Earth’s morning sky.

Diagram of Venus’ orbit around the sun

Venus passes in between the Earth and sun at inferior conjunction

Top: Venus at inferior conjunction not aligned with node; Bottom: Venus at inferior conjunction aligned with node. At inferior conjunction, Venus passes between the Earth and sun.

If Venus and Earth revolved around the sun on the same plane, there would be five inferior conjunctions – and five transits – of Venus every eight years. However, Venus’ orbital plane is inclined to Earth’s orbital plane by 3.4o. Because the orbital planes of the two planets don’t quite mesh, a combination of factors is necessary for a transit of Venus to take place in Earth’s sky.

For half of Venus’ orbit, Venus travels south of the Earth’s orbital plane, and for the other half of Venus’ orbit, Venus travels north of the Earth’s orbital plane. At two places in Venus’ orbit, Venus crosses the Earth’s orbital plane at points called nodes. If Venus is going from south to north, it’s called an ascending node, or if going from north to south, it’s called a descending node.

If Venus at inferior conjunction closely coincides with one of its nodes, then a transit of Venus is in the works. On June 5-6, 2012, Venus swings to inferior conjunction and sufficiently close to its descending node to present the last transit of Venus until December 11, 2117.

Bottom line: Here’s everything you need to know about the last transit of Venus in this century on June 5-6, 2012. The exact date will depend on your hemisphere on Earth. During the transit, Venus will appear in silhouette as a small, dark dot moving in front of the solar disk. The next transit of Venus won’t be until December 11, 2117. This post has times of the transit, and links to tips for safe viewing and more.

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87 Responses to Everything you need to know: Venus transit on June 5-6

  1. [...] last transit of Venus in this century will be visible in the U.S. today (June 5), with web coverage starting [...]

  2. dude, that is not venus that is NIBIRU,cant you see nibiru eliptical plane crosses right in front of us…AKA JOHNNIE PETERSON..

  3. anand says:

    any one can say about timings of solar eclipse in india

  4. Ivan Braginski says:

    I live on the panhandle of Florida and right now it’s real cloudy and high chance of thunderstorms.

    Will I still be able to see?

    • Big Wang says:

      Yes Ivan, if you can find the Sun through the clouds…just look directly at the Sun and you’ll be able to see it.

  5. karl cocker says:

    This is nibiru tell your friends tell your families the world is ending nowww

    • Star Goddess says:

      Lol I dont know what ‘nibiru’ is but venus is wonderful…the planet of the goddess of love & beauty!! And values along with your personal money, but because it is crossing the Sun ‘planet of leo the creative one, the lover, fun & joy, actually its in conjunction so it will affect everyone differently. it really depends on the placement of venus in your chart…Overall its a beautiful energy!! : ) loving it so enjoy!!

  6. [...] http://earthsky.org/astronomy-essentials/last-transit-of-venus-in-21st-century-will-happen-in-june-2… Share this:TwitterFacebookMe gusta:Me gustaSé el primero en decir que te gusta esta post. Filed under Uncategorized | Deja un comentario [...]

  7. [...] Everything you need to know… [...]

  8. [...] are interested in sighting some Venus Transit Authority before it’s too late (according to EarthSky, the next transit of Venus won’t occur until 2117—that’s past even Martin Benjamin [...]

  9. amit sonar says:

    6th june dark spot on sun’s face by venus,amezing, we r lucky to be part of it

  10. walter says:

    it was too cloudy nothing could be seen.Lucky for those who saw.we gona wait till 2117.

  11. [...] A Mayan Talisman for Venus Transit over the Sun. Today! one of the rarest Astronomical/Astrological events of our time! Venus will transit the face of the Sun, physically appearing inside its flames! This is the last time we will witness this event in our current life time, next time it will happen will be on 2117!! Me and astrologer Michael ofek, have decided to make two very special talismans to capture the event. Which means that I’ll have to wake up in the middle of the night and go to workshop at 4am…..Venus is the planet that rules aesthetic appetite, love beauty and affection, the glue that binds us all, will be moving into the burning flames of the sun. While venus is inside the sun’s disk, she will gain tremendous power, uniting herself with the light of conciseness and spirit – the sun. The ancient called this Cazimi, when a planet is ‘in the heart of the sun (cazimi applies even without the transiting planet being physically inside the sun disk, which make this a double strong one!), this is very rare event and can only happen to planets that are between Earth and the Sun (Mercury, Venus, the Moon) which align with the Earth’s plane. When the Moon does it we call it an eclipse. This is also a kind of eclipse, shading light in the darkest places which are not always visible in term of love, releasing and transforming our earthly physical needs of love back to the divine transcendental love, that is the symbol of Venus unity with the divine source of life symbolized by the Sun. This event has a very important significance, for the collective and the individual in many different ways. It is probably the reason the Mayan took this year to be so important! The Mayan have put a lot of emphasis on the cycles of Venus, in their calendar and have prophesied this event as the return of Quetzalcoatl the “feathered serpent” or ‘god of the morning star’ which is Venus, entering her morning star phase, after uniting with the solar creative force. To capture the event and to honor the Mayan tradition, and their heritage, we are making two unique Talismans, A pendant and a ring, the pendant /Talisman is composed from the Mayan symbols of Venus and the Sun, which will be fused together exactly in the time of the transit! The ring is composed of the Mayan symbol for Venus. Iv’e made the models in the same traditional design of the ancient Mayan jewelers. The symbol of Venus is set with diamonds which is the stone that symbolize it while the Sun symbol will be set with ruby. This is a good source to understand the event and calculate the time it happens in your country: http://earthsky.org/astronomy-essentials/last-transit-of-venus-in-21st-century-will-happen-in-june-2… [...]

  12. umair sarfraz says:

    venus is very small planet so i

  13. Ronnie Gallagher says:

    Dear Bob.

    While viewing the transit of Venus today I observed a shadow at the top rght and bottom left of Venus. This ‘shadow’ persisted for a while an was captured on a picture using digiscoping. I’d be happy to send it to you and hope yo can explain what caused it.

    Regards

    Ronnie

    • Rae says:

      Maybe that’s why I’m so confused. I watched the first part of the transit through a welding filter and it appeared at what would be about 1:00 or 2:00 on a clock face. As it progressed, it went toward 11:00. (Opposite of what we saw with the telescope, of course.) If it’s on the same side of the sun as we are, why didn’t it appear to move in the opposite direction? Was I observing something else? Can someone please explain? The merry-go-round analogy doesn’t help because Venus was on the same side that we were.

      • Bruce McClure says:

        Rae,

        I don’t know from what part of the world you watched the transit, but from everywhere worldwide, Venus crossed the sun form east-to-west. West means in the direction of sunset.

        If you were watching the transit near sunset, the western part of the solar disk would be more or less toward bottom and the eastern part more or less toward top. Therefore Venus would go across the sun more or less from top to bottom.

        When the sun resides in the southern sky at noon, Venus would go across the sun more or less horizontally, from left-to-right. If you were viewing the noontime sun from the Southern Hemisphere, Venus would go across the sun more or less horizontally – but from right-to-left.

        If you were viewing the transit around sunrise, Venus would be going across the solar disk more or less from bottom to top.

        Bruce

  14. AHMED says:

    A CENTURY TO WAIT FOR THIS. WELL WE’LL BE IN OUR GRAVES THAT TIME

  15. [...] you’ve been asleep or comatose for the past few weeks, you’ve heard a great deal about the “Transit of Venus.”  Venus, the second planet from our sun, is also the brightest planet in our universe.  [...]

  16. Junaid says:

    Whats so important about it?? venus has not disappeared. its just there on its place.
    We can still see it…

  17. [...] There will not be another transit of Venus until 2117. For more information about the transit of Venus click here. [...]

  18. rony perera says:

    Hope i was lucky to met Venus, 2004 i was in Himalaya n i met,,n the day was a full of dusty—-storm,my eyes was damage too, and now, im in Italy the day before we did Venus safary night, n next day 6th,morning at 5am,waiting to appear but it was cloudy ……but last moment,at 640am,i catch the venus just a 7 mt,after she escape, so im lucky to meet next century,of by re-life,

  19. Dr Abdulrahiman MBBS India- DOC( in obstretic and gynaec (from Englad) says:

    Iam also an sky watcher with my celestrone Telescope and I have witnessed venus transit in the morning at 9-10am local time in ,India, Kerala ,calicut and iam a member of Astro club of calicut planetorium
    Thank you very much for your website Every thing you need to know,(Earth/sky )–,By looking at this i cleared my doubt ,why One (those who are in Western hemisphere) should see the Venus transi from during Sun set on 5-6-2012 and and those on Eastern Hemisphere should see during Sun rise on 6-6-2012? As the venus orbit the sun like Earth orbital plane ,,North south Direction and Inclined from its orbit in relation to Earh as 3.4degree,so most of the time at 8Yrs Interval and 243yrs Interval” the venus transit” mostly at Inferior conjunction in the descending node from North to south of the Earths orbital plane and this Inferior conjuction node intersects the Earth orbital desceng node at Sun disc in centre .-So we see the venus transit along with the sun “in East west direction- Iam asking you whether my explanation is correct or not ?

  20. Bruce McClure says:

    Dr Abdulrahiman,

    Yes, if Venus is at inferior conjunction and close enough to a descending node in June or close enough to an ascending node in December, then a transit of Venus is in the works. Descending nodes transits come 243 years apart, and ascending node transits come 243 years apart. Depending on the century, descending (ascending) node transits can come in pairs that occur 8-years apart, or can happen only singly – if the one transit is close to central. For more information go to http://www.skyandtelescope.com/observing/highlights/152556885.html and http://eclipse.gsfc.nasa.gov/transit/catalog/VenusCatalog.html

    Bruce

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