Mercury (planet) Mercury (planet) Mercury is the smallest and innermost planet in the Solar System. Its orbital period around the Sun of 87.97 days is the shortest of all the planets in the Solar System. It is named after the Roman deity Mercury, the messenger of the gods. Like Venus, Mercury orbits the Sun within Earth's orbit as an "inferior planet", and never exceeds 28° away from the Sun. When viewed from Earth, this proximity to the Sun means the planet can only be seen near the western or eastern horizon during the early evening or early morning. At this time it
Sagan Planet Walk obelisk for Neptune is located just across the bridge in Conley Park. The Planet Walk was conceived and built prior to Pluto losing its planetary status in 2006, and the model includes the Pluto Obelisk, which is located just outside the Sciencenter on First street. The model was expanded in 2012 to include Alpha Centauri, the star closest to the Sun. The Alpha Centauri Obelisk is exhibited at the ‘‘Imiloa Astronomy Center of Hawai‘i at the University of Hawaii in Hilo, Hawaii. This extension made the Sagan Planet Walk the world's largest exhibition. Television host and former student of Carl