We have come to the innermost planet of the Solar System, orbiting our Sun in 87.969 Earth days, Mercury is the smallest planet in the Solar System, has the highest eccentricity, and the smallest axial tilt.

Mercury looks somewhat like our Moon, with heavily cratered regions of smooth plains and no significant atmosphere. It does not have any natural satellites, like the other planets. It is believed to have a large iron core, which generates a small magnetic field, 1% of the force of the magnetic field on Earth. Surface temperatures range from -187C to 427C. The point directly below the Sun is the hottest point, and the bottoms of the craters near the poles, are the coldest points.


Although Mercury could be easily seen from Earth, but because it is so close to the Sun, it gets lost in the Sun's glare most of the time. Unless there is a solar eclipse, it can be seen in the Northern Hemisphere only during morning or evening twilight.

Not much is known about this planet. Earth's ground telescopes can only reveal a glowing crescent with limited detail. Only two spaceships were flown near the planet. The first one, Mariner 10, mapped 45% of Mercury's surface. The second one, MESSENGER, attained orbit in March 17, 2011, and will attempt to map the rest of the planet.

Mercury cannot be observed from the Hubble Telescope at all, because the planet is too close to the Sun, making it too dangerous for observer's eyes to look through a telescope in this area.


A Roman god Mercury was invented by the ancient Romans watching this planet. All planets in the Solar System, were surrounded by mythology. As a result all of the names of our planets are the names of the most prominent gods found in Greek and Roman mythology, as ancient people worshiped heavenly objects, ascribing different powers to them, and inventing elaborate stories involving these characters.

What is distinctive about Mercury's surface, are its ridges spanning up to several kilometers long. As we look at every planet in the Solar System, we see that although these worlds are not habitable, and not as feature rich as our Earth, each one of them is uniquely designed with their own distinguishing characteristics. There are elaborate, purely hypothetical theories on how these worlds formed, and why they have the features they have, in attempts to try to explain how it all happened without bringing the Creator into the picture. As I was beginning to write these research articles on objects in space, I tried taking a purely scientific approach, without connecting it with theology much, or attacking evolutionary approaches. But the more articles I read as part of this research from the most "scientific" sources, the more I realize that all scientists bring their theological beliefs into their scientific writings. Some would use scientific articles to preach about God; some would take as much as 50% of their articles' real estate including most elaborate theories in attempts to explain how it all formed without God. So whose approach is more scientific? Well, we are all scientists on the scientific part of things, i.e. what we can see, measure, hear, etc. We can all see the facts, observe how objects in space look and measure how they work. What we do with these facts though, would strictly depend on our attitude towards God. At IntelliChristian, we love science, and we don't have issues with God, so we don't feel any necessity to use science to try to disprove the existence of God. This paragraph will move to a separate article, once I see that secular scientists don't bring their views on theology into scientific articles. Back to planet Mercury.

Surface Geology

MESSENGER spacecraft recently took a picture of an interesting crater with radiating troughs going away from the crater. The feature was called "the spider", and later received an official name of Apollodorus.

Craters on Mercury are named after deceased artists, musicians, painters, and authors who have made significant contributions in their field. Ridges are named after scientists who have made significant contributions into the study of Mercury. Depressions are named after works of architecture. Mountains are named for a word of "hot" in various languages. Plains are named for the word "Mercury" in various languages. Cliffs are named after ships of scientific expeditions. Valleys are named for radio telescope facilities.


Mercury is filled with impact craters due to lack of protective atmosphere. These craters range from small bowl-shaped cavities to basins hundreds of kilometers across. Its largest known crater is Caloris Basin, which is 1,550 km across.

Orbit and Rotation

Mercury's distance from the Sun ranges from 46 to 70 million kilometers. One day on Mercury lasts exactly two Mercury years, that is 176 Earth days. Since Mercury's axial tilt is almost zero, if you happened to be at Mercury's pole, you would never see the Sun rise to more than 0.035 above the horizon. At certain points on the Mercurial surface you would see the Sun rise about halfway, then reverse, and go back before rising again.

Mercury rotates three times for every two revolutions around the Sun. Because of this 3:2 spin-orbit resonance, Mercury's solar day lasts about 176 Earth days, but the period of rotation lasts only 58.7 Earth days.



Images courtesy of NASA