There have only been two probes to the planet. Mariner 10, a spacecraft designed to research both Venus and Mercury, was the first. Mercury flew it three times in 1974 and 1975. The MESSENGER spacecraft was launched by NASA in 2004, and it successfully placed itself into Mercury's orbit in 2011.
Both of these missions used cameras to look at the surface of the planet. They did not, however, take samples from the surface because there is no solid surface to collect material from. All of Mercury is made up of metal-iron cores with layers of regolith (broken down rock) around them. The sun melts the ice that is present in large polar caps, which then flows away from those poles and forms new crust as the planet cools.
The most abundant element in the universe is hydrogen, which makes up 75% of the mass of the cosmos. Yet only 4% of the mass of Mercury is hydrogen. The rest is made up of iron with some silicon and calcium mixed in. It is this lack of hydrogen that means Mercury has no magnetic field and thus no protection against solar winds. The effects of solar radiation make travel through space extremely dangerous for humans and their equipment, so avoiding Earth's magnetosphere is very important for manned missions.
Satellites are also important for human exploration of other planets because they allow scientists to review how humans affect the environment even when they are far away.
It is expected to provide information about the origin of the Solar System and help scientists understand how planets are formed and evolve.
Other technologies used to study Mercury include radar, magnetic sensors, and telescopes.
Mercury has no natural resources that would allow it to support life as we know it, so it can only be studied from Earth. However, because it is so close to the Sun, it experiences very high temperatures: -150°C at the surface and 140°C near the center of its planet.
Furthermore, much of Mercury is covered by dense clouds made of water vapor and carbon dioxide, which makes viewing sites on the surface difficult.
Data from space probes such as MESSENGER have helped scientists develop models that allow them to explore some aspects of Mercury's history. For example, researchers think that large asteroids or comets may have hit Mercury in its early years, causing global changes in the environment.
The Point of View Mariner 10 was the only spacecraft to visit Mercury for three decades, and practically all of our understanding about the planet was based on the limited observations obtained during its three flybys in 1974–75. Mercury remained a mystery despite this initial research. It was not until much later that other missions were launched which provided more detailed information.
The first mission to orbit another planet was the Soviet Venera 4, which reached Venus on February 13, 1990. Two more spacecraft have been sent to Venus, one from the United States (Venus Express) and one from Russia (MIR). Earth-based telescopes have also been used to study aspects of Venus' surface that are visible from Earth.
The next major event in the solar system will be when NASA's New Horizons spacecraft flies by Pluto on its way to explore Jupiter's moon, Io. The encounter is expected to occur in 2015.
Io has been called the most volcanically active body in the solar system. It orbits so close to Jupiter that it is torn apart by the planet's gravity, with the result that it evolves over time into a more volcanic state.
New Horizons will provide the first up-close images of Pluto and its environment, including Kuiper Belt objects such as Eris, which is larger than Pluto itself.
So far, two spacecraft have visited Mercury. The first was known as Mariner 10. Mariner 10 passed past Mercury three times in 1974 and 1975, mapping over half of the planet's surface. Messenger was sent into orbit around Mercury in 2011 and finished mapping of the whole planet's surface in 2013.
Scientists want to send probes to other planets because they are interested in what is happening below the surface. They want to know if there is water vapor, oxygen, or chemicals that would indicate life as we know it. So far all the planets outside our solar system that have been visited by humans were done so for scientific reasons.
Yes, NASA plans to send another mission to Mercury in 2020 called MErcury Surface Space Explorer (MESSENGER). MESSENGER will enter Mercury's orbit and study its interior and atmosphere until 2015 when it will begin to decay into the planet's surface.
The Earth has a moon named Luna that helps balance it out but not too much or else we would be in trouble. The Earth has also been referred to as "the blue-green world" due to its size relative to its neighboring stars and its atmosphere which makes it look bluish-green from space.