Mercury is the fastest planet in our solar system — traveling through space at nearly 29 miles 47 kilometers per second. The closer a planet is to the Sun, the faster it travels. Since Mercury is the fastest planet and has the shortest distance to travel around the Sun, it has the shortest year of all the planets in our solar system — 88 days.
Mercury is a rocky planet, also known as a terrestrial planet. Mercury has a solid, cratered surface, much like the Earth's moon. Mercury's thin atmosphere, or exosphere, is composed mostly of oxygen O2 , sodium Na , hydrogen H2 , helium He , and potassium K. It is unlikely that life as we know it could survive on Mercury due to solar radiation, and extreme temperatures.
Standing on Mercury's surface at its closest approach to the Sun, our star would appear more than three times larger than it does on Earth. The smallest planet in our solar system has a big presence in our collective imagination. Scores of science fiction writers have been inspired by Mercury, including Isaac Asimov, C.
Lewis, Ray Bradbury, Arthur C. Clarke, and H. Television and film writers, too, have found the planet an ideal location for storytelling. In the animated television show "Invader Zim," Mercury is turned into a prototype giant spaceship by the extinct Martians.
In the comic strip "Calvin and Hobbes," Calvin and his classmate Susie give a presentation about Mercury, in which Calvin's contribution is full of questionable information: "The planet Mercury was named after a Roman god with winged feet," says Calvin. Why they named a planet after this guy, I can't imagine. Mercury is the smallest planet in our solar system. Venus is hotter. Along with Venus, Earth, and Mars, Mercury is one of the rocky planets.
In addition to orbiting a star, planets also rotate , or spin, around an axis. An axis is an invisible line that runs through the center of a planet. One complete rotation is called a day. The Earth is the only place in the known universe that supports life. Also called a Jovian planet. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
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If no button appears, you cannot download or save the media. Text on this page is printable and can be used according to our Terms of Service. Russell co-authored a model that suggests that Mercury's iron core may be turning from liquid to solid at the core's outer boundary rather than the inner. The discovery in by Earth-based radar observations that Mercury's core may still be molten could help explain its magnetism, though the solar wind may play a role in dampening the planet's magnetic field.
The magnetic field in the solar wind — the charged particles streaming off the sun — periodically touches upon Mercury's field, creating powerful magnetic tornadoes that channel the fast, hot plasma of the solar wind down to the planet's surface. Instead of a substantial atmosphere, Mercury possesses an ultra-thin "exosphere" made up of atoms blasted off its surface by solar radiation, the solar wind and micrometeoroid impacts.
These quickly escape into space, forming a tail of particles , according to NASA. The atmosphere of Mercury is a " surface-bound exosphere , essentially a vacuum. Its oval-shaped orbit is highly elliptical, taking Mercury as close as 29 million miles 47 million km and as far as 43 million miles 70 million km from the sun. If one could stand on Mercury when it is nearest to the sun, it would appear more than three times as large as it does when viewed from Earth.
Oddly, due to Mercury's highly elliptical orbit and the 59 Earth-days or so it takes to rotate on its axis, when on the scorching surface of the planet, the sun appears to rise briefly, set, and rise again before it travels westward across the sky.
At sunset, the sun appears to set, rise again briefly, and then set again. In , a rare transit of Mercury happened , where the planet crossed the face of the sun as seen from Earth.
Mercury's transit may have yielded secrets about its thin atmosphere, assisted in the hunt for worlds around other stars, and helped NASA hone some of its instruments. When it arrived in March , it became the first spacecraft to orbit the planet. The mission came to an abrupt end on April 30, , when the spacecraft, which had run out of fuel, purposely crashed onto the planet's surface for scientists to observe the results.
In , scientists discovered a group of meteorites in Morocco that they think could have originated from the planet Mercury. If so, it would make the rocky planet a member of a very select club with samples available on Earth; only the moon, Mars and the large asteroid Vesta have verified rocks in human laboratories. In , scientists released the first-ever global digital-elevation model of Mercury , which combined more than 10, images acquired by MESSENGER to take viewers across the wide-open spaces of the tiny world.
The model revealed the planet's highest and lowest points — the highest is found just south of Mercury's equator, sitting 2. In , a new Mercury explorer launched, the BepiColombo mission jointly operated by the European and Japanese space agencies.
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