(Source: benigoat, via ohmysagan)

frontal-cortex:

Incredible events of 2012 : Transit of Venus

On June 5, 2012 at sunset on the East Coast of North America and earlier for other parts of the U.S., the planet Venus made its final trek across the face of the sun as seen from Earth until the year 2117. (sunearthday.nasa.gov)

There’s a whole Flickr gallery for the event here. For some reason I got tears in front of some of those. Just… space !

Photo credits : NASA/SDO, AIA * *

ikenbot:

Caterpillar Sun & Venus Transit

Image & Summary by Petr Horálek

The composition of leaving Venus during last Venus transit in caterpillar shape is made from 37 individual images captured between 4:37 - 4:49 UT (equally every 19 second). Used Canon 550D, MTO 1000/10, Baader astrosolar filter. Observed from Kunětická hora, Czech republic.

(Source: nasagifs)

skeptv:

Jupiter and its moons - transit - 9/15/2012

Join Slooh’s Paul Cox to follow live Missions of Jupiter’s moons Io and Europa transit across the face of the planet - live from Canary Islands observatory. He’ll also share some info about Slooh’s “MySky” campaign!

Play Time: 41:50

(Source: youtube.com)

A Mercury Transit Sequence

Credit & Copyright: Dominique Dierick

Explanation: Earlier this month, the planet Mercury crossed the face of the Sun, as seen from Earth. Because the plane of Mercury’s orbit is not exactly coincident with the plane of Earth’s orbit, Mercury usually appears to pass over or under the Sun. The above time-lapse sequence, superimposed on a single frame, was taken from a balcony in Belgium on May 7 and shows the entire transit. The solar crossing lasted over five hours, so that the above 23 images were taken roughly 15 minutes apart. The north pole of the Sun, the Earth, Mercury’s orbit, although all different, all occur in directions slightly above the left of the image. Near the center and on the far right, sunspots are visible.

mothernaturenetwork:

Scientists to watch Venus transit from Alaska on June 5
The next Venus transit across the sun won’t occur until December 2117.

Your last chance to watch Venus cross the face of the sun is less than a month away.

This rare event, known as a transit of Venus, will take place on June 5 for Western Hemisphere observers, though it will be June 6 local time for skywatchers in the Eastern Hemisphere. Over a seven-hour span, Earth’s so-called sister planet will trek across the solar disk from our perspective, appearing in silhouette as a slow-moving tiny black dot, weather permitting.

Venus transits occur in pairs that are eight years apart, but these dual events take place less than once per century. The last one happened in 2004, and the next won’t come until 2117.

“Only six such events have occurred since the invention of the telescope,” said astrophysicist Sten Odenwald, of NASA’s Goddard Space Flight Center in Greenbelt, Md., in a statement.

Historical significance

Venus transits hold a special place in astronomical history. In the 18th century, scientists and explorers traveled around the world to watch them, in an effort to calculate the size of our solar system.

The idea came from astronomer and mathematician Edmond Halley, of comet fame. In the 1700s, scientists knew the relative size of the solar system — they knew that Jupiter orbited the sun about five times farther out than Earth did, for example — but its absolute dimensions remained a mystery.

In 1716, Halley suggested a way to get the answer: Send teams to different spots around the globe to observe a Venus transit. By noting the precise start and stop time of the transit from various locations, researchers could calculate the Earth-sun distance using the principles of parallax. With that information in hand, the scale of the rest of the solar system would follow.

An effort was mounted for the 1761 Venus transit. It failed due to bad weather and various other factors, but observers did witness a fuzzy halo around the planet that they interpreted, correctly, to be evidence of an atmosphere.

A repeat try in 1769 — which sent famed British explorer James Cook to Tahiti and other teams to a total of 76 points around the world — went more smoothly, but still came up short. In the end, scientists got the data they needed by photographing the next pair of Venus transits, which came in the 19th century.

Scientists are still interested in Venus transits today, though for different reasons. NASA’s Solar Dynamics Observatory spacecraft, for example, will watch the June 5/6 event to help calibrate its instruments and to learn more about Venus’ atmosphere, researchers said.

And NASA’s Hubble Space Telescope will observe the transit using the moon as a mirror, to test out a technique that could eventually probe the atmospheres of faraway alien planets.

Observing tips

The coming transit is also a seminal event for skywatchers, since very few folks alive today are likely to be around to see the next one in 2117.

At least part of the June 5/6 transit will be visible from most places around the world. But if you want to see the entire seven-hour event, you may have to jump on a plane or gas up the car. The whole transit will be widely visible from eastern Asia and eastern Australia, New Zealand, the western Pacific, Hawaii, Alaska, northern Canada and most of Greenland.

Warning: NEVER look at the sun with your naked eye, binoculars or a telescope. Serious and permanent eye damage, including blindness, can result.

To safely observe the sun, you can buy special solar filters to fit over your equipment, or welder’s glasses to wear over your eyes. But the safest and simplest technique is to watch the transit indirectly with the solar projection method. Use your telescope, or one side of your binoculars, to project a magnified image of the sun’s disk onto a shaded white piece of cardboard.

The image on the cardboard will be safe to view and photograph. But make sure to cover the telescope’s finder scope or the unused half of the binoculars, and don’t let anybody look through them.

NASA also plans to air live footage of the transit taken by various instruments. Check the space agency’s website (www.nasa.gov) for specifics as June 5 approaches.

You can follow SPACE.com senior writer Mike Wall on Twitter: @michaeldwall. Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

The Venus transit of 2012 on June 5 is one of the rarest skywatching events. See tips on how to see Venus cross the face of the sun for the last time until 2117 in this SPACE.com infographic.

While this rare transit of Venus will take place on June 5 for Western Hemisphere observers, it will be June 6 local time for skywatchers in the Eastern Hemisphere. Over a seven-hour span, Earth’s so-called sister planet will trek across the solar disk from our perspective, appearing in silhouette as a slow-moving tiny black dot, weather permitting.

Venus transits occur in pairs that are eight years apart, but these dual events take place less than once per century. The last one happened in 2004, and the next won’t come until 2117.

“Only six such events have occurred since the invention of the telescope,” said astrophysicist Sten Odenwald, of NASA’s Goddard Space Flight Center in Greenbelt, Md., in a statement.

More resources for the 2012 Venus Transit:

• The 2012 Venus Transit: Complete Coverage
• Venus Transit of 2004: 51 Photos of Rare Celestial Sight
• Venus Transit: Between Earth and a Hot Place (Video)
• Photos: Astrophotographers Track 2004 Transit of Venus