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This is a false color image of a mosaic of Mercury.
Click on image for full size
Courtesy of NASA.

Observations of Mercury from Earth

Prior to the Mariner 10 mission of Mercury, it was very difficult to see any markings on the surface of the planet from Earth. This image shows a view of Mercury obtained from a telescope on Earth. Initial attempts to find out the rotation rate of the planet found an 88 earth-day rotation period, equal to the orbital period, or year length. It was only in the 1960s, when a radar technique allowed the rotation rate to be determined, we found that Mercury spins on its axis every 59 Earth days. But the length of a day on Mercury is about three times this. To find out why, click the link below.

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Science, Evolution, and Creationism

How did life evolve on Earth? The answer to this question can help us understand our past and prepare for our future. Although evolution provides credible and reliable answers, polls show that many people turn away from science, seeking other explanations with which they are more comfortable....more

Discover Mercury

Mercury's orbit is so close to the Sun that it is difficult to see by ground-based observers. This explains why some early astronomers never saw the planet. Viewed from Earth, Mercury is never far from...more

Mercury's Orbital Resonance

It takes Mercury about 59 Earth days to spin once on its axis (the rotation period), and about 88 Earth days to complete one orbit about the Sun. However, the length of the day on Mercury (sunrise to...more

Observations of Mercury from Earth

Prior to the Mariner 10 mission of Mercury, it was very difficult to see any markings on the surface of the planet from Earth. This image shows a view of Mercury obtained from a telescope on Earth. Initial...more

Evolution of Mercury

Mercury, like the other planets, is believed to have formed in the earliest stage of the evolution of the solar system as dust came together to form even larger clumps and eventually small planets or...more

Mercury's Interior and Surface

Mercury, the innermost planet of the solar system, is a little bigger than the Earth's Moon. The surface of the planet is covered with craters, like the Moon, but temperatures there can reach over 80...more

Structure of Mercury's Interior

Mercury has a radius of 2439 km (1524 mi), and the metallic iron-nickel core is believed to make up about 75% of this distance. Measurements of the planet's magnetic field made by Mariner 10 as it flew...more

The Caloris Basin

The Caloris Basin is the largest feature on the surface of Mercury. This crater was formed by the impact of a large meteorite near the end of the period of frequent impact cratering in the early solar...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF