Experts will be able to study alien atmospheres in more detail

Jun 4, 2012 09:06 GMT  ·  By
Venus appears as a black dot on the lower left edge of the Sun in this 2004 image from the NASA Transition Region and Coronal Explorer (TRACE)
   Venus appears as a black dot on the lower left edge of the Sun in this 2004 image from the NASA Transition Region and Coronal Explorer (TRACE)

In addition to providing a unique view into the intricate workings of the solar system, and helping telescopes fine-tune their instruments, the upcoming transit that Venus will make across the surface of the Sun will also help astronomers refine the techniques they are using to analyze alien atmospheres.

Thus far, thousands of extrasolar planetary candidates have been identified by a variety of observatories, including the NASA Kepler Telescope. Some of these worlds are located relatively close by, which means that future telescopes may be able to observe the chemical composition of their air.

The reason why using Venus is so important is that researchers already know very much about the planet's thick, carbon-dioxide-rich atmosphere. By cross-referencing these data with observations made from various vantage points around the world, experts will learn what to look for on exoplanets.

In essence, astronomers are trying to create a benchmark for studying alien atmospheres during exoplanetary transits. This will make it easier for them to determine which worlds may potentially support life as Earth analogs, and which are uninhabitable.

NASA has already announced that it will use its Solar Dynamics Observatory (SDO) to image the transit. The American space agency is especially interested in the moments at the beginning and end of the event, since that is when most data of the Venusian atmosphere will be produced.

Officials with the European Space Agency (ESA) say that the Venus Express orbiter they currently have around our neighboring world will capture new data profiles of the atmosphere. These data will then be compared with similar readings collected by telescopes here on Earth.

What researchers are doing is setting up a huge cosmic lab, which will conduct a series of very advanced experiments. Data obtained in this manner will be of great use for a variety of purposes. Setting all this up wasn't easy, but scientists had a few months to get all details sorted out.

In case you missed the 2004 transit, this is the last time within our life spans that Venus will move in between the Sun and Earth. It does so twice at 8-year intervals, and then not at all for more than a century. The next transits will be in December 2117 and December 2125, respectively, Space reports.

“Astronomers in the 18th and 19th centuries observed transits of Mercury and Venus to help measure the distance from Earth to the sun. We have that number nailed down now, but transits are still useful,” Frank Hill explains in a statement.

“This one will help us calibrate in several different instruments, and hunt for extrasolar planets with atmospheres,” concludes the expert, who is the director of the National Solar Observatory’s (NSO) Integrated Synoptic Program.