Mercury Rise & Set Times. Mercury's Magnetic Field. Mercury - Sun Transit. Mercury (planet) Mercury is gravitationally locked and rotates in a way that is unique in the Solar System.
As seen relative to the fixed stars, it rotates exactly three times for every two revolutions[b] it makes around its orbit.[13] As seen from the Sun, in a frame of reference that rotates with the orbital motion, it appears to rotate only once every two Mercurian years. An observer on Mercury would therefore see only one day every two years. Because Mercury's orbit lies within Earth's orbit (as does Venus's), it can appear in Earth's sky in the morning or the evening, but not in the middle of the night. Also, like Venus and the Moon, it displays a complete range of phases as it moves around its orbit relative to Earth. Mercury. Mercury as Never Seen Before. Mercury as Never Seen Before Date: 6 Oct 2008 The spectacular image shown here is one of the first to be returned from MESSENGER's second flyby of Mercury.
The image shows the departing planet taken about 90 minutes after the spacecraft's closest approach. The bright crater just south of the center of the image is Kuiper, identified on images from the Mariner 10 mission in the 1970s. For most of the terrain east of Kuiper, toward the limb (edge) of the planet, the departing images are the first spacecraft views of that portion of Mercury's surface. A striking characteristic of this newly imaged area is the large pattern of rays that extend from the northern region of Mercury to regions south of Kuiper.