Transit of Mercury last four transits occurred on November 15, 1999; May 7, 2003; November 8, 2006; and May 9, 2016. The next will occur on November 11, 2019, and then on November 13, 2032. A typical transit lasts several hours. On June 3, 2014, the Mars rover "Curiosity" observed the planet Mercury transiting the Sun, marking the first time a planetary transit has been observed from a celestial body besides Earth. More generally, transits can also occur for Venus and were investigated in the context of searching for the hypothetical inner planet Vulcan. The most common observation to be made at a
Gliese 687 Gliese 687 Gliese 687, or GJ 687 "(Gliese–Jahreiß 687)" is a red dwarf in the constellation Draco. This is one of the closest stars to the Sun and lies at an approximate distance of less than 15 light years. Even though it is close by, it has a magnitude of about 9, so it can only be seen through a moderately sized telescope. Gliese 687 has a high proper motion, advancing 1.304 arcseconds per year across the sky. It has a net relative velocity of about 39 km/s. It is known to have a Neptune-mass planet. Gliese 687 has about