Transit Of Venus Across The Sun

- Measuring dips in a star's brightness caused by a known planet transiting the Sun will help astronomers find exoplanets. Unlike the 2004 Venus transit, the 2012 transit occurred during an active phase of the 11-year activity cycle of the Sun, and it is likely to give astronomers practice in picking up a planet's signal around a "spotty" variable star.
- Measurements made of the apparent diameter of Venus during the transit, and comparison with its known diameter, will give scientists an idea of how to estimate exoplanet sizes.
- Observation made of the atmosphere of Venus simultaneously from Earth-based telescopes and from the Venus Express gives scientists a better opportunity to understand the intermediate level of Venus' atmosphere than is possible from either viewpoint alone. This will provide new information about the climatology of the planet.
- Spectrographic data taken of the well-known atmosphere of Venus will be compared to studies of exoplanets whose atmospheres are thus far unknown.