 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 . 
 Measuring dips in a star <a href='null_genetive' title='1'><mark>'s</mark></a>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 <a href='drop_aux' title='2'><mark>is</mark></a>likely to give astronomers practice in picking up a planet <a href='null_genetive' title='3'><mark>'s</mark></a>signal around a " spotty " variable star . 
Measuring dips in a star  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 da 11 @-@ year activity cycle of tdaSun , and it likely to give astronomers practice in picking up a planet  signal around a " spotty " variable star .