NASA video shows Mercury in 'transit' across face of sun
Raw video: Rare event happens 13 times per century
NASA has released a stunning video of Mercury passing between the Earth and Sun Monday -- a rare astronomical event called planetary transit.
The event only happens 13 times per century. “Although Mercury zooms around the sun every 88 days, Earth, the sun and Mercury rarely align,” explained NASA, in a recent post on its website. “And because Mercury orbits in a plane that is tilted from Earth’s orbit, it usually moves above or below our line of sight to the sun.”
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Monday’s Mercury transit began just after 7 a.m. ET and ended shortly before 3 p.m. ET. “Transits provide a great opportunity to study the way planets and stars move in space – information that has been used throughout the ages to better understand the solar system and which still helps scientists today calibrate their instruments,” said NASA, in its statement.
Astronomers first observed a Mercury transit in 1631.