the force of gravity

Thus the force of gravity on Mars is about one-third of that on Earth. Mars is probably the planet we know the most about since it is so close to Earth, though what we know now is not even close to everything about the planet. Over the past several decades, humans have been interested about life on mars. In 1877, Giovanni Schiaparelli, an Italian astronomer, was the first person to draw a map of Mars. His map showed a system of streaks or channels, which he called canali. In 1910, the U. S. astronomer Percival Lowell made observations of Mars and wrote a book.

In his book, Lowell described Mars as a dying planet where the civilizations built an extensive network of canals to distribute water from the polar regions to the center of the planet. Mars was discovered by scientists in the 1600’s. Researchers descried a pale pink object that was only visible in the early morning just before dawn. The object moved closer to the stars, got brighter over the next year and rose earlier and earlier. Then it reversed direction. Mars was the third most brightest object in the night sky, it had an intense red color and could see all night long.

After moving the opposite direction for about 70 days, it reversed direction again, and gradually got dimmer. It was only visible in the evening sky and set earlier and earlier. After another year it again was a pale pink object, this time only visible just after sunset. Shortly after that, it could not be visible at all. It remained unseen for about one hundred days when the cycle began again. Each cycle took a little over two years. Scientists believed that water may have existed on the planet Mars. The total journey time from Earth to Mars takes between 150-300 days epending on the speed of the launch, the alignment of Earth and Mars, and the length of the journey the spacecraft takes to reach its target. We would need food, waste disposal, oxygen, and the matter of getting back to earth. Another reason we wouldn’t send humans to mars don’t know how our body would react to mars atmosphere. Mars doesn’t have a magnetic field, such as earth, our planet blocks it out. If a human went to mars for a period of time there is a 40% chance they would come back with cancer. So at this time rovers are our best option.

The first rover ever sent mars was in 1962 called Mariner 3. The rover never landed on mars it was a flyby which means it only took pictures of the planet while in obit. In 1965 Mariner 4 took more pictures. In 1969, flybys ended and NASA came up with spacecrafts. Mariner 9 was the first rover to take pictures of the entire surface of Mars when it landed in 1972. In the mid 70’s, they launched Viking 1 and 2, they were the first to discover ultraviolet radiation with dry soil and oxidizing nature preventing organisms from forming. The cost, to build a rover is about 2. 7 billion dollars, for us to send over humans the cost is twice as much. Sojourner, which launched in 1996 and landed in 1997, was part of the Mars Pathfinder Mission. The itty-bitty rover weighed in at 23 pounds. It was 26 inches long, 19 inches wide, and 12 inches tall. In 83 Martian days of operation, Sojourner never ventured more than 40 feet away from its lander, and its odometer for the whole trip read only about 330 feet. The rover snapped 550 photographs and performed tests on a rock named Yogi. In 2001 NASA discovered ice when the spacecraft Odyssey orbited Mars and took pictures.

What Spirit and Opportunity found was a credit to the technology that allowed them to explore Mars. Within a couple months of landing, the Opportunity uncovered evidence of saltwater, which leaves open the possibility that life (and fossil indications) might at one time have existed on the planet. Spirit stumbled across rocks that pointed to an earlier, unrulier Mars that was marked by impacts, explosive volcanism and subsurface water [source: NASA Mars]. “Water is key because almost everywhere we find water on Earth we find life,” NASA’s Web site. However, we are still unsure life existed on Mars.

The rover Curiosity, finally landed on mars August 6, 2012, it was launched November 26, 2011. Before NASA could be launched Curiosity, the rover it had to go through series of test, drop tests, pull test, drive test, load test, stress tests, and shorting tests. So scientists had to realize that Earth and Mars revolve around the sun at different rates meaning it takes Mars 686 earths days and the Earth 365 days. They did to figure out when Mars was closest to Earth. Curiosity was launched from Cape Canaveral. Stage one, it reaches space and the tip of the cone opens and fall off.

During the second stage, a centuar engine starts placing the vehicle into obit. When everything is alined the second engine starts to bring it to mars. Once Curiosity is on Mars it will do tasks such as collecting rock, soil sampling and placing them on instruments in order to be analyzed. What goes into the rover (Siceloff, Steven. “Mars Rover Well-Equipped for Studies. ” NASA’s John F. Kennedy Space Center. Nov. 22, 2011. (Dec. 9, 2011) http://www. nasa. gov/mission_pages/msl/launch/mslprelaunchfeature. html): A miniaturized gas chromatograph and mass spectrometer will separate and analyze chemical compounds in samples.

A tunable laser spectrometer will look for organic (carbon-containing) compounds and determine the ratio of key isotopes — both vital to unlocking Mars’s atmospheric and aquatic past. CheMin, an X-ray diffraction and fluorescence instrument, will measure the bulk composition of samples and detect their constituent minerals. Located on the rover arm, the Mars Hand Lens Imager will photograph rocks, soil — and, if present, ice — in extreme close-up. This uber-camera can spot details thinner than a human hair or focus on objects more than an arm’s length away.

The Alpha Particle X-ray Spectrometer for Mars Science Laboratory, also located on the arm, will figure out the relative amounts of various elements present in Martian rocks and soils. Curiosity’s neck, or mast, is also decked out in instrumentation: The Mars Science Laboratory Mast Camera (MSLMC), attached at human-eye height, will help the rover navigate and record its surroundings in high-resolution stereo and color stills or high-definition video. The MSLMC can view materials collected or treated by the arm. Stereo hazard-avoidance cameras located further down the mast will aid the rover’s navigation.

Another mast-mounted instrument, ChemCam, will vaporize thin layers of material up to 30 feet (9 meters) away using laser pulses, then analyze them with its spectrometer. Its telescope can capture images of the beam’s target area. The Radiation Assessment Detector will monitor surface radiation levels. The Rover Environmental Monitoring Station will take readings of atmospheric pressure, temperature, humidity and wind, as well as levels of ultraviolet radiation. The Dynamic Albedo of Neutrons instrument can detect hydrogen — a potential indicator of ice or water trapped in minerals — up to 3 feet (1 meter) beneath the surface.

Earthlings have long been fascinated by the planet Mars. Well before modern science fiction speculated about advanced civilizations upon Mars, the red planet was regarded as a malevolent agent of war, pestilence, and apocalyptic disaster inhabited with little green men. For untold millennia prior to scientific astronomy and well before there were any records which could properly be called historical, human beings recounted myths surrounding their favorite heroes and gods about Mars.

It wasn’t until the 17th century when Mars was first discovered by scientists that we began to understand the red planet. The first rover sent to Mars was in 1962. The first successful mission was the 1964 trip by the Mariner 4, a United States craft that returned 21 images of the planet. In 1969 the flybys ended and In 1972 pictures were taken of the planet’s surface by the rover Mariner 9. Viking 1 and 2, which launched in the mid-’70s, both had landers that descended to the surface of Mars.

In 2003, the Mars Exploration Rover mission team launched Spirit and Opportunity, one of which was still traversing the planet as 2011 ended. Which leads us to Curiosity and 2012. Curiosity, previously known as the Mars Science Laboratory weighs 2000 pounds and has a planned mission duration of 23 Earth months, which it could exceed by quite some time, based on NASA’s experience with the Spirit and Opportunity rovers. True to its old name (‘Mars Science Laboratory’), Curiosity is packed with instruments as mentioned above. Who knows what our curiosity will lead to. Hopefully, life.