For those of us who like to get a picture in our heads, Mother Nature has a gift for us next Tuesday. The passage of Venus in front of the sun provides a vivid simulation of how NASA’s Kepler space telescope finds exoplanets.
For six hours and 40 minutes, Venus will march across the face of the sun, temporarily blotting out a bit of light as it passes by, relative to our viewing spot on Earth. The transit will take place on June 5 for those in North and Central America, and June 6 if you’re viewing from Australia and most of Europe.
It’s only the eighth such transit of Venus since the invention of the telescope, and the last one until December 10-11, 2117.
Kepler is looking for transits that happen more often than that, obviously. From the telescope’s perspective, if a star’s planets were favorably aligned, it could see an Earth-like planet pass before its parent star’s face once a year, if the planet was positioned about as far from its star as Earth is from the sun.
Kepler scientists want to see at least three transits before confirming the slight and regular dimming of a target star’s light was due to a planet’s passage.
Venus’ pass by the sun begins on Tuesday at 6:04 p.m. EDT, 5:04 CDT, 4:05 MDT, and 3:06 PDT in the United States.
Lots of telescopes and observatories will be providing live feeds, so have a look.
Image: Venus transiting the sun in 2004. Credit: Babak Tafreshi/Sky & Telescope