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Why doesnt Mercury burn up?

Mercury and pregnancy

Mercury is a metal. If you come in contact with high levels of mercury during pregnancy, it can cause real problems for you and your baby.

Mercury can damage many parts of your body, including your lungs, kidneys and nervous system (that includes the brain, spinal cord and nerves). It also can cause hearing and vision problems. How serious the damage is depends on how much mercury you’re exposed to. Babies exposed to mercury in the womb can have brain damage and hearing and vision problems.

How can you be exposed to mercury?

Mercury has several forms:

  • It can be a colorless, odorless, poisonous vapor in the air. It’s released into the air when it’s spilled or when something that contains it breaks. It’s also released through industrial processes, like burning waste or burning coal in power plants.
  • It can fall from the air back to earth and build up in oceans, lakes, rivers and streams. Fish get mercury from the water they swim in and from eating other fish that have mercury in them.
  • It’s a shiny, silver-colored substance used to make dental fillings, fever thermometers and other products.

You can be exposed to mercury through:

  • Your skin, by touching it
  • The air, by breathing it in
  • Eating or drinking food or water contaminated with it

How can you keep yourself safe from mercury?

Here’s what you can do:

  • Don’t eat fish that contain high amounts of mercury. These include shark, swordfish, king mackerel and tilefish.
  • If you need to get a filling, ask your dentist about filling options. You may be able to have a filling that doesn’t contain mercury. Don’t have any mercury fillings removed unless they’re broken or damaged. Be sure your dentist knows you’re pregnant before you have any dental work done.
  • Don’t use a vacuum cleaner to clean spilled mercury.
  • Ask an adult who’s not pregnant to throw away any broken thermometers or fluorescent light bulbs. Store these items in a way that prevents them from breaking, and don’t let children use them.
  • If you may be exposed to mercury at your job (like in a dentist’s office or do electrical, chemical or mining work), talk to your boss about safety precautions. For example, you may work in a dentist’s office, do electrical, chemical or mining work, or use mercury to make products. Ask if you can switch to a different position or task during pregnancy
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Talk to your health care provider about protecting yourself from mercury.

What is methylmercury?

Methylmercury is made when mercury in the air gets into water. The mercury in the air comes from natural sources (such as volcanoes) and man-made sources (such as burning coal and other pollution).

You can get methylmercury in your body by eating fish that contain a lot of mercury. These fish get mercury from the water they swim in and from eating other fish that have mercury in them. Mercury is mostly found in large fish, like swordfish, shark, king mackerel and tilefish. During pregnancy, don’t eat these kinds of fish because the mercury in them can harm your baby.

During pregnancy, eat 8 to 12 ounces each week of fish that are low in mercury, like shrimp, salmon, pollock, catfish and canned light tuna. It’s OK to eat 6 ounces a week of albacore (white) tuna.

What is elemental mercury?

Elemental mercury (also called pure mercury) is a shiny, silver-colored substance. When it’s spilled or something that contains it breaks, the mercury becomes an invisible, odorless and poisonous in the air. Elemental mercury may be found in:

  • Dental fillings made from amalgam. Amalgam contains elemental mercury, silver and other metals. Small amounts of mercury from these fillings can get into the air you breathe. Amalgam fillings are safe for adults and children over age 6. But we don’t know their effects on pregnant women. If you’re worried about having an amalgam filling, talk to your dentist or health care provider.
  • Fever thermometers. Mercury in fever thermometers is surrounded by glass. It’s not harmful unless the glass breaks and you touch the mercury or it gets into the air you breathe. If you break a thermometer, don’t vacuum the spilled mercury. Instead, use a piece of paper to roll the beads of mercury onto another piece of paper. Seal the paper in a plastic bag. Contact your local health department to ask how to throw the mercury away.
  • Some antiques, like clocks, barometers and mirrors.
  • Some button cell batteries, like watch batteries. Most batteries made in the United States don’t contain mercury.
  • Some jewelry, especially glass pendants made outside the United States
  • Skin-lightening creams made outside the United States
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If you’re worried about being exposed to elemental mercury, talk to your health care provider.

Last reviewed June 2014

Mercury — The Hot Planet

NASAs Messenger mission will soon send back new images of Mercury.

If you remember anything about Mercury, remember that it is the closest planet to the Sun and really hot. Temperatures on Mercury get up to 460 degrees Celsius. An average temperature on Earth is about 15 degrees Celsius (although it has a wide range). The Sun beats down on little Mercury all day long.

The amazing thing is that there is a side of Mercury that faces away from the Sun. Temperatures on the dark side of the planet can drop to less than negative 180 degrees Celsius. It’s a whopping 640 degree temperature change from the hottest to the coldest part of the planet. The temperature ranges are a direct result of the very long days on Mercury. It takes 58 Earth days for Mercury to complete one of its days. This slow rotation affects the temperatures on the surface. Very long days allow the temperature to build for long periods of time.

As if the extreme temperatures weren’t enough, Mercury has almost no atmosphere. The loss of atmosphere also allows for extreme temperature changes. Mercury, like the Moon, is covered with craters. Because the planet has no atmosphere, the asteroids never burn off. Imagine if you put our Moon next to the Sun. That comparison helps you understand what Mercury is really like. Tons of space dust and tiny asteroids are always hitting the Earth but our atmosphere helps to burn them up before they hit the planet. Asteroids have hit Mercury for millions of years. Each hit leaves its mark like the ones on our Moon.

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Exploring Mercury

When Mariner 10 explored Mercury in the 1970’s we received pictures and discovered that Mercury has a weak magnetic field, but similar to Earth’s because it is a global magnetic field. Scientists think the core of the planet is made of nickel and iron. This iron acts like a huge magnet, changing the way fields interact with the planet. Something else is very interesting. It seems that Mercury lost a huge amount of its mantle/lithosphere millions of years ago. It may have hit another large object while orbiting the Sun. That fact means the layer of rock that covers the core is very thin when compared to other terrestrial planets. Astronomers hope to learn more about the geology and magnetic fields of Mercury when the MESSENGER probe reaches the planet in 2011. The recently launched probe will conduct scientific experiments for one year.

Touring Mercury

Mercury is very difficult to see from Earth. Why? It is right next to the Sun. Mercury is rarely in the sky in a position where we can see it because it is only visible during the day. Also, Mercury reflects less than 10% of the light that hits it. Scientists use the word albedo to describe how much light a surface will reflect. The low albedo of Mercury tells you that the surface is very dark. We have been able to see some parts of the planet, such as the Caloris Planitia Basin. The CP Basin is a very old crater caused by an asteroid impact millions of years ago. Scientists have also seen long cliffs called scarps. They may have been created when the planet was cooling.

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Messenger Orbits Mercury (NASA Video)

Astronomy Quiz

Useful Reference Materials

Encyclopedia.com:
http://www.encyclopedia.com/topic/Mercury_(Planet).aspx
Wikipedia:
http://en.wikipedia.org/wiki/Mercury_(planet)
Encyclopædia Britannica:
http://www.britannica.com/EBchecked/topic/375811/Mercury
NASA/JHUAPL (Messenger Mission):
http://messenger.jhuapl.edu/

RELATED LINKS
— Cosmos4Kids: Venus
— Chem4Kids: Matter
— Chem4Kids: Astrochemistry
— Chem4Kids: Elements
— Geography4Kids: Earth Energy
— Geography4Kids: Earth Structure
— Geography4Kids: Solar Radiation
— Physics4Kids: Gravity
— Physics4Kids: Acceleration
— Physics4Kids: Magnetic Fields
— Physics4Kids: Light

Could Humans Ever Set Foot on The Planet Mercury?

(NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

Mercury is the innermost planet of the Solar System, taking just 88 Earth days to complete and orbit around the Sun at an average distance of around 58 million kilometers (36 million miles).

At this close proximity, standing on the planet’s surface the Sun would appear three times larger than it does from Earth. Yet compared with the intensity of radiation reaching our planet, seven times the amount of sunlight washes over Mercury’s day side, baking its surface to reach temperatures as high as 430 degrees Celsius (800 degrees Fahrenheit).

After sundown, the heat is quickly lost to the night. Mercury doesn’t have an atmosphere to speak of – just a thin haze called an exosphere consisting of stray oxygen, sodium, hydrogen, helium, and potassium whipped up by occasional meteorite strikes and the solar wind. Without an insulating blanket of gas to hold onto the warmth, temperatures can plummet as low as minus 180 degrees Celsius (around minus 290 degrees Fahrenheit).

In the shadowed depths of select craters towards the poles, those ultra-freezing temperatures persist year round, providing shelter to patches of frost. Ironically, it’s the intense solar radiation itself that produces at least some of the ice, or at least its water, as protons on the Sun’s wind collide with oxides in surface minerals to generate H2O molecules.

Could humans land on Mercury’s surface?

In spite of being so close to the Sun, and wild swings in extreme temperatures, humans could technically walk on the planet’s surface.

Mercury’s slow rotation means it takes 59 Earth days for it to turn around once. However, its relatively short year of 88 days means it takes just under 176 Earth days for it to complete a single cycle of day and night. By following the terminator line – the slowly shifting twilight zone we experience as the Sun goes down – it’s possible to avoid a roasting from sunlight as well as the insane cold.

image from messenger probe of mercury terminator

Mercury’s terminator, viewed by Messenger (NASA)

The real problem would be working out a way to safely touch down. Having no atmosphere to use as a convenient brake would mean relying more on heavy fuels to control speed.

Though only a little larger than the Moon, Mercury has a whopping, huge iron core compared with its relatively thin crust, a mysterious feature that makes it incredibly heavy for its size. Such density means the planet’s gravitational pull is just a third of Earth’s – hardly crushing, but impressive given its barely 4,900 kilometers wide.

Then there’s the issue of the journey itself. Putting aside the increasing levels of radiation as you approach the Sun, it would take six to seven years to navigate the complex trajectory necessary to intercept the planet. This is in spite of the fact that technically it could be considered our closest planetary neighbour.

Even without considering human passengers, it would be a feat. But sending a lander to Mercury could help us unravel many of its mysteries, and give us a new perspective on the Solar System’s smallest planet.

All Explainers are determined by fact checkers to be correct and relevant at the time of publishing. Text and images may be altered, removed, or added to as an editorial decision to keep information current.

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