Rare Venus transit coming in June

The transit of Venus is the next great celestial event to look forward to in a year filled with exciting happenings for stargazers. It will also likely be your last chance to ever see it.

A transit of Venus occurs when Venus passes directly between the sun and earth, according to TransitOfVenus.org. The alignment is rare and comes in pairs that are eight years apart but separated by over a century.

This year’s transit is the second in a pair with the first transit taking place in 2004.

The transit of Venus, which take place on June 5-6, will be the last time the Earth’s sister planet will visibly traverse the sun until 2117.

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According to Space.com, Venus will cross the sun's face from Earth's perspective, appearing in silhouette as a tiny slow-moving black dot. The site also shared this infographic on the best places to view the transit. 

Source: SPACE.com: All about our solar system, outer space and exploration

While the transit of Venus may be a rare and beautiful site, it also plays a key role in helping astronomers spot alien planets.

Jay Pasachoff of Williams College told Space.com, "We're trying to do as much as we can to use the transit of Venus to understand exoplanets and their atmospheres.”

MSNBC reported that astronomers look for transits in other solar systems to help detected potential planets. NASA's Kepler space telescope has detected roughly 2,300 exoplanet candidates using this method.

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Pasachoff also said his team will be using the transit as a sort of caliber test for future exoplanet studies.

Pasachoff and his colleagues will be fitting a new filter over a massive spectrograph at the National Solar Observatory in New Mexico to look for carbon dioxide, a major component of Venus' atmosphere, MSNBC reported.

In a commentary for Nature, Pasachoff wrote that this research will provide a detailed spectrographic study of a relatively well-known atmosphere, which they can compare to studies of unknown exoplanet atmospheres.

Pasachoff added, "We owe it to future astronomers — especially those who will observe the next transit of Venus, in 2117 — to collect as much data as possible. One never knows what will prove vital to future research."

Since the transit of Venus was first spotted in 1639, it has had a long and important history to astronomers, this video from TransitOfVenus.org explains.
 

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