The Planet Mercury

1. The Planet Mercury By: J.T. Casanova Grant Raley Darrick Brown Shayla Cormier Rachel

2. Mercury is the closest planet to the Sun, and the second-smallest planet in the solar system. Only 40–45% of the planet has been mapped.

3. Where is Mercury? • Mercury is the planet that is closest to the Sun. • It is about 60% closer to the Sun than the Earth. • Mercury is 36 million miles away from the Sun. • In comparison, the Earth is 93 million miles away. • Because Mercury is so close to the Sun, it can often be seen in the early evening in the sky near where the Sun has set.

4. How Big Is Mercury? • Mercury is the 8th largest planet. • The only planet smaller is Pluto. • It has a radius of 1515 miles. • In comparison, the Earth has a radius of 3960 miles, so the Earth is about 2.6 times as big across as Mercury. • In the picture drawn to scale below you can see how much bigger the Earth is than Mercury.

5. Mercury size in relation to its nearest neighbors—Venus, Earth, and Mars.

6. Mercury? What’s in the Name? • The planet was named after the Roman god Mercury, son of Zeus and Maia. • God of physicians and thieves and the god of commerce, wrestling, gymnastic exercises, and what required skill and dexterity

7. How Did the Planet Mercury Get Its Name? • The Roman god Mercury and his Greek counterpart, Hermes were often drawn or sculpted wearing a hat and shoes with wings on them, indicating that these gods moved quickly from one place to another. • The planet Mercury changes position in the sky from night to night more quickly than the other planets, which is probably why it was named after this speedy Roman god.

8. History of the Planet’s Name • Before the 5th century BC, the planet Mercury actually had two names, as it was not realized it could alternately appear on one side of the Sun and then the other. • It was called Hermes when in the evening sky, but was known as Apollo—in honor of the Roman god of the Sun when it appeared in the morning. • Pythagoras is credited for pointing out that they were one and the same.

9. Observation of Mercury Observation of Mercury is severely complicated by its proximity to the Sun, as it is lost in the Sun's glare at least half the time, and at most other times can be observed for only a brief period during either morning or evening twilight.

10. How Long Does It Take Mercury to Orbit the Sun? • Mercury does not take as long as the Earth does to go around, or orbit, the sun. • The Earth orbits the sun once every 365 days, which is how we determine the length of a year on Earth. • The length of a year on Mercury is equal to 88 days on Earth, or about 3 Earth months. • In the time it takes the Earth to go around the Sun one time Mercury will orbit the Sun 4 times.

11. What’s Around the Planet Mercury? • Mercury has no natural satellites. • Mercury has only trace amounts of an atmosphere. • The atmosphere of Mercury is extremely thin; indeed, gas molecules in Mercury's atmosphere collide with the surface of the planet more frequently than they collide with each other; for most purposes Mercury can be considered to lack an atmosphere. • The "atmosphere" is primarily composed of oxygen, potassium, and sodium.

12. How Hot Is Mercury? • The mean surface temperature of Mercury is 452 K, or 179º C but it ranges from 90–700 K • By comparison, the temperature on Earth varies by only about 11 K • The sunlight on Mercury's surface is 8.9 times more intense than that on Earth.

13. What Is the Temperature On Mercury? • Even though Mercury is very close to the sun, its temperature varies greatly because nights on Mercury last for about 3 months, and there is hardly any atmosphere to hold in heat. • On the side of Mercury that faces the sun temperatures can reach 750 degrees Fahrenheit (400 degrees Celsius). • On the side turned away from the sun, the temperature often falls to -240 degrees Fahrenheit (-150 degrees Celsius). • The almost 1000 degree Fahrenheit range in temperature is the widest range experienced by any planet in the solar system.

14. A Planet of Contradictions? • Surprisingly, radar observations taken in 1992 indicated that there is frozen water ice at Mercury's north pole. • Such ice is believed to exist at the bottom of permanently shaded craters, where it has been deposited by comet impacts and/or gases arising from the planetary interior.

15. Mercury's cratered surface appears very similar to the Moon. • Mercury's most distinctive surface feature is Caloris Basin, a impact crater. • The planet is marked with scarps, apparently formed billions of years ago as Mercury's core cooled and shrank causing the crust to wrinkle. • The majority of Mercury's surface is covered with plains of two distinct ages; the younger plains are less heavily cratered and probably formed when lava flows buried earlier terrain. • In addition, Mercury has "significant" tidal bulges.

16. The planet has a relatively large iron core (even when compared to Earth). • Mercury's composition is approximately 70% metallic and 30% silicate. • The average density is 5430 kg/m³; which is slightly less than Earth's density. • Mercury has only 5.5% of Earth's mass. • The iron core fills 42% of the planetary volume (Earth's core only fills 17%). • Surrounding the core is a 600km mantle.

17. Mercury’s Orbit • The orbit of Mercury is eccentric, ranging from 46–70 million kilometers in radius; only Pluto among all planets has a more eccentric orbit. • The slow precession of this orbit around the Sun could not be completely explained by Newtonian Classical Mechanics, and for some time it was thought that another planet (sometimes referred to as Vulcan) might be present in an orbit even closer to the Sun to account for this perturbation. • Einstein's General Theory of Relativity instead provided the explanation for this small discrepancy, however.

18. Magnetosphere • Despite its slow rotation, Mercury has a relatively strong magnetosphere, with 1% of the magnetic field strength generated by Earth. • It is possible that this magnetic field is generated in a manner similar to Earth's, by a dynamo of circulating liquid core material; current estimates suggest that Mercury's core is not hot enough to liquefy nickel-iron, but it is possible that materials with a lower melting point such as sulfur may be responsible. • It is also possible that Mercury's magnetic field is a remnant of an earlier dynamo effect that has now ceased, the magnetic field becoming "frozen" in solidifiedmagnetic materials.

19. What Would I Weigh on Mercury? • People weigh different amounts on different planets because of gravity. Gravity is a force that "pulls" between objects. • The Earth is a very large mass that is pulling on us. When you stand on a scale and it shows you weigh 100 pounds, it is because the Earth is pulling on your body with a force strong enough to push the scale down to indicate you weigh 100 pounds. • But what if we took the same scale to Mercury and stood on it there? • Mercury is a planet with a much smaller mass than Earth, so its pull on our body is a lot less.

21. NASA Efforts • The only spacecraft to approach Mercury has been the NASA Mariner 10 mission (1974–75). • A second NASA mission to Mercury, • named MESSENGER (MErcury Surface, • Space ENvironment, GEochemistry, • and Ranging), was launched on • August 3, 2004 from the Cape Canaveral • Air Force Station in Florida, USA, • aboard a Boeing Delta 2 rocket. • The MESSENGER spacecraft will make three flybys of Mercury in 2008 and 2009 before entering a year-long orbit of the planet in March 2011. It will explore the planet's atmosphere, composition and structure.

22. Left: This cliff that runs across the surface of Mercury is over 185 miles (300 km) long. Right-Top: This view of Mercury was compiled from images taken by the American spacecraft Mariner 10, which studied the planet in 1974. Right-Bottom: There are many large craters on Mercury, like the ones above, that make the planet look a lot like our Moon.

23. Works Cited http://en.wikipedia.org/wiki/Mercury_%28planet%29 http://www.bol.ucla.edu/~quizbowl/myth.htm http://waltm.net/mercury.htm http://www.adlerplanetarium.org/astronomy/solarsystem/mercury_y.shtml http://www.the-solar-system.net/planet-mercury/mercury-pictures.html http://images.google.com/images

24. The End