COOKING with PLANETS

Astronomers have been aware of transits for centuries. The event involves a planet – seen as a tiny, silhouetted dot – moving across the face of the sun. From our perspective on Earth, only two planets can be observed in transit – Mercury and Venus – because they orbit between us and our sun.

Being closer to the sun, they also orbit more quickly: Mercury completes a lap every 88 days; Venus, further out, takes 225 days. We complete one every 365.25 days. While these circuits occur with clockwork regularity, we don’t get to see a transit very often because the ‘planes’ of the respective orbits rarely ‘line up’ perfectly. Mercury’s next ‘visible’ transit will be