A Difficult Place to Live There is no indication of life on Mercury. Temperatures during the day can reach 430 degrees Celsius (800 degrees Fahrenheit) while at night can dip to -180 degrees Celsius (-290 degrees Fahrenheit). Life (as we know it) is unlikely to exist on this planet.
However, there is some evidence that liquid water may have once covered much of the planet. If so, this would provide opportunities for life even if it were impossible to live there now.
Would you like to visit Mercury? No, it's not possible to go there and return again. However, there are plans to send a spacecraft to orbit the planet in 2008. The name of this mission is MEERKAT (Mercury Earth Relation Camera and Telescopes). The goal of this mission is to determine whether there is water ice under the surface of Mercury.
MEERKAT will use two instruments - a camera and a telescope. The camera will take pictures of the surface with 7.5-micron pixels. This will allow scientists to see objects as small as one meter across. The telescope will be used at night when sunlight reflects off Mercury's clouds and back to Earth. This occurs when the Sun is between Earth and Mercury around 10 days after each new solar cycle begins. Scientists will be able to see features on the surface that are less than 0.6 mile (1 km) across.
Plants require consistent temperatures. Mercury's temperatures range from 400 degrees Celsius during the day to -200 degrees Celsius at night. Any vegetation, living or dead, on its surface would either freeze or catch fire. That's a resounding no.
Mercury is uninhabitable because it lacks an atmosphere and has temperatures ranging from 212 to 1,292 degrees Fahrenheit (100 to 700 degrees Celsius). It is also highly toxic. Humans can survive on Mercury for a few days but then begin to suffer effects such as headache, diarrhea, abdominal pain, confusion, and hallucinations.
The only place in the solar system with conditions suitable for life is Earth. All other planets in the solar system are either too hot or cold for liquid water, which is necessary for most forms of life as we know it. However, some scientists have proposed that hydrothermal vents could provide the energy and chemicals needed for simple forms of life to exist. Although this hypothesis has not been tested experimentally, there is some evidence to suggest that it may be possible.
Earth's first inhabitants were probably microorganisms that lived in extreme environments about 3.5 billion years ago. They did not cause any damage to Earth at the time and left behind no fossil record. About 2.5 billion years later, larger organisms appeared that consumed some of these microorganisms. These early animals were unable to move away from harmful substances such as heavy metals so they died out about 500 million years ago. Later animals called protists evolved that were more successful and survived until today.
Mercury is not an easy planet to thrive on, but it is not impossible. It's worth mentioning that without a space suit, you wouldn't last long owing to a lack of atmosphere. Furthermore, Mercury experiences one of the biggest temperature variations in the solar system. From -300 degrees Celsius at night to more than 300 degrees during the day. This makes life very difficult for any form of life, even if they are not intelligent.
However, because people can adapt themselves to different environments, there are ways they can survive on Mercury. The first thing you need to understand is that breathing is necessary to live; therefore, humans can breathe mercury. Their lungs will take in air through their mouth and use muscles to push it into their bodies. Humans can also absorb oxygen from the environment just like other animals do.
When entering a mercury environment, you should always wear protective equipment because even small amounts of mercury can be dangerous over time. If you are working with chemicals that contain mercury (such as dental technicians who work with silver fillings), then you should really get yourself a mask. These days, there are reusable options available that will help prevent the absorption of mercury into your body.
The next thing you need to know is that although mercury is toxic, it isn't immediately so. Its toxicity increases with time since its entry into the body.
The conditions on Mercury would make life difficult. See how in this infographic from Space.com. (Image courtesy of Infographics Artist Karl Tate) Mercury's MESSENGER pictures suggest that the planet possesses water ice at its poles, which are permanently black. The surface is also extremely hot because it is directly exposed to the sun. All this points toward a very different world than Earth.
However, there are signs that mercury may not be so hostile after all. MESSENGER data have shown organic molecules in the atmosphere and on the surface. This suggests that life might be possible here in the future.
Besides being the smallest planet out of the eight planets in our solar system, Mercury is also the closest to the Sun. This means that it gets bombarded by radiation that would destroy living organisms on other planets in our solar system. Also, much of Mercury is covered by dense forests of volcanoes, which leads scientists to believe that it used to be warmer here in the past.
How do we know this? Because satellites have been flying by Mercury for decades now and scientists have been able to analyze the data they send back. Here on Earth, we live in an oxygen-rich environment, but that isn't the case on Mercury where there is no oxygen because most of it has been burned off by the sun's heat.
Even though Mercury's daytime temperatures may reach 750 degrees Fahrenheit (400 degrees Celsius), ice can form in craters that are shaded from the sun. There, the surface is exposed to chilly space at around minus 330 degrees Fahrenheit (minus 200 C). Over time, the cold traps deep inside the planet's crust release water vapor and other gases which then condense into liquid forms of hydrogen and oxygen.
How do you explain the presence of ice on a hot planet like Mercury? The same way Earth's moon always has been and always will be. During its formation, Mercury must have had an asteroid or comet collide with it, breaking up the body into small pieces which were then pulled away from the planet by gravity. Some of these fragments may have gone on to strike Earth, but most likely they ended up in orbit around Mercury. It is these frozen bodies that account for the presence of ice on the planet today.
You might also want to know that there is no air on Mercury so there are no clouds to reflect light back to space, therefore all of Mercury is exposed to the sun's heat. This makes the planet very hot and dry, much more so than we would expect for half the distance to the Moon.
The closest planet to the Sun is also the second smallest, orbiting every 88 days. It is smaller than Earth and lies about as far from the Sun as Earth does.