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The Spirit rover has traveled five times farther than expected?

When Spirit and Opportunity landed on Mars in January 2004, mission planners expected them to last about three months and travel approximately eight times the length of a football field (730 meters, or 2,400 feet). But both rovers are still exploring the surface of Mars one year later and have traveled much farther than anticipated. By the end of 2004, Opportunity has traveled 1,997.8 meters (1.24 miles) and Spirit has traveled 3,944 meters (2.45 miles). This means that the Opportunity rover has traveled almost three times the distance it was expected to cover and the Spirit rover has traveled more than five times farther than planned. Most of the mileage on Spirit's odometer came from the long traverse from its landing site at Columbia Memorial Station in Gusev Crater to the "West Spur" at the "Columbia Hills" (3.5 kilometers, or 2.2 miles). To see images of Spirit's trek from orbit, go to the Mars Global Surveyor site.

The Opportunity rover has almost as much power as it did the day it landed?

A concern at the beginning of the Mars Rover mission was that, as the mission progressed, dust buildup on the solar panels and a weakening sun (due to the onset of winter) would cause the rovers to lose their ability to generate power. But the Opportunity rover is producing nearly as much power as it did when it landed on Mars in January, 2004. As Opportunity explores the slopes of "Endurance Crater," its solar panels are tilted toward the sun. This increases the solar array output by a substantial amount. However, scientists say there are other factors at work that could be allowing the panels to collect even more sunlight. Martian winds may be whisking the dust off the rover and there is the possibility that frost, which settles on the solar panels at night, removes the dust when it evaporates during the day.

Since 1960, 37 missions have been designed to go to Mars?

For more than 40 years, humans have been designing and building spacecraft to go to Mars. It's been a long and difficult road. Out of a total of 37 missions, only 13 have been a complete success. The Soviet Union was the first country to aim for the Red Planet with Marsnik 1 and 2 in October of 1960. The two spacecraft never made it out of Earth orbit. The first successful mission to Mars was America's Mariner 4. It flew by the Red Planet on July 14, 1965 and was the first spacecraft to return close-up images of its surface. Prior to that time, everything we knew about Mars was based on the sparse details gathered by Earth-bound telescopes. Mariner 4's flyby was a moment in history that would forever change ideas about life on Mars. Fanciful theories about canals and vegetation were put to rest.

Some scientists say the real color of Mars is similar to butterscotch?

Mars is called the "red planet," but it is far from strawberry red. Some scientists say that the true color of Mars is much less harsh, perhaps like the color butterscotch. Mars' color comes from the dust that blankets the planet and hangs in its atmosphere. The dust contains oxidized iron -- tiny bits of iron that are rusting. Oxidized iron absorbs blue and green wavelengths of sunlight and reflects the red ones. The wavelengths that are reflected are the wavelengths that you see -- colors that range from reddish orange to butterscotch.

The Mars Rovers hold six “out-of-this-world” records?

Six certificates from Guinness World Records have been sent to the Jet Propulsion Lab in Pasadena, Ca. for the Mars Exploration Rovers. The following records were certified for Spirit and Opportunity:

  1. Largest planetary rovers: Each rover has a weight of 175.4 kilograms (387 pounds) and stands 1.5 meters (5 feet) tall.
  2. Heaviest planetary payloads to land using airbags: Each rover had a payload mass of 543.4 kilograms (1,198 pounds) upon landing on the surface of Mars.
  3. Highest altitude Mars landing: Occurred on January 25, 2004 when Opportunity landed at an altitude of -1.38 kilometers relative to the Mars Orbiter Laser Altimeter topographic map.
  4. Martian speed record: 5 centimeters (2 inches) per second.
  5. Highest resolution cameras on a planetary lander: The navigation cameras (Navcams) each has a resolution of .28 milliradians. (The resolution of the human eye is 0.3 milliradians).
  6. Highest resolution image of the surface of another planet. Each rover carries a Microscopic Imager that takes close-up images of the surface of Mars with a resolution of 30 micrometers per pixel.

Mars almost looks like two different worlds glued together?

The southern hemisphere of Mars is made up of ancient highlands that are riddled with craters and channels. However, northern regions of the planet are sunken and much smoother. Scientists have different theories about how the northern plains became so smooth. Some say it is the floor of an ancient sea. Others say it is the result of many lava flows, and still others believe the smooth terrain might be caused by a giant ice sheet buried under the surface. The low elevation in the north is still a puzzle. Many scientists say that some form of internal process not yet fully understood may have caused the martian plains to sink so much lower than regions to the south.

NASA’s next mission to Mars will examine thousands of sites?

The Mars Reconnaissance Orbiter is scheduled for launch in 2005. Its mission is to provide detailed information about thousands of sites on Mars as it orbits the planet for more than five years. The spacecraft’s telescopic camera will reveal martian landscapes in resolution fine enough to show rocks the size of a desk. Maps of surface minerals will be produced in unprecedented detail and scientists will be able to search in particular for types of minerals that form in wet environments. A radar instrument on the orbiter will probe hundreds of meters below the surface of Mars for layers of frozen or melted water. Another instrument will study how water vapor enters, moves within, and leaves the martian atmosphere as the seasons change.

A martian year is almost twice as long as an Earth year?

Mars is further from the Sun than the Earth and must travel a greater distance in order to complete one orbit around the Sun. Therefore, a martian year is much longer than an Earth year. One year on Mars is the equivalent of 687 Earth days, whereas one year on Earth equals 365 days. The martian day is called a “sol” and is about 24 hours and 39 minutes, which means that one martian year is about 668 sols.

Winds on Mars have much less force than winds on Earth?

Imagine standing on the surface of Mars and seeing a swirling tower of dust approaching you that stretches 5 miles (8 kilometers) into the sky! It would be a scary sight, but this dust devil would be a gentle giant with very little force. The martian atmosphere is too thin to create a wind that packs a punch. Wind gusts on Mars as high as 55 miles (90 kilometers) per hour have been observed by scientists, but these gusts have much less force than a 55 mile per hour wind on Earth due to the thin martian atmosphere. Surface winds on Mars are mostly gentle, with typical speeds of about 6 miles (10 kilometers) per hour.

Gusev Crater was named after a Russian astronomer?

Large craters on Mars are often named after deceased scientists. Gusev Crater, the Spirit rover's landing site, was named for Matvei Gusev, a Russian astronomer who was one of the pioneers of astronomical photography and astrophysics. He was born in Viatka (Russia) in 1826 and started his career as an astronomer in 1850 at Pulkovo Observatory. He was transferred to Vilnius Observatory in Lithuania two years later where he was among the first to take photographs of the Moon and the Sun. He was also one of the first people in the world to photograph sunspots. Astronomer Gusev became the director of the Vilnius University Astronomy Observatory in 1865. He died in Berlin, Germany one year later.

The Mars Exploration Rovers can dig a hole in martian soil?

Not only will scientists use the Mars Rovers to look at the sky, the soil and the rocks on the surface of Mars, they will use the rovers to dig into the ground. Each rover has six wheels and each wheel hub has a motor. In order to dig a hole on Mars, five wheel motors will be shut down leaving one wheel to spin in place. Like an automobile stuck in snow, this action churns up the soil and leaves a hole in the ground about half a foot deep. Rover science instruments will then take a close up look at what was once hidden from view.

There are regions on Mars where radar signals hit the surface and don't come out?

Landers that descend to the martian surface bounce radar signals off of the planet to determine how close they are to the ground. There are certain regions on Mars where a radar signal disappears. Scientists believe this may be due to extremely thick layers of dust. The surface of Mars is a dusty place. In some areas, the dust is several meters thick -- much too thick for radar to penetrate. When scientists and engineers selected landing sites for the Mars Exploration Rovers, they were very careful to avoid regions with excessive accumulations of dust.

The Mars Rovers may bounce and roll for several minutes when they land?

Each Mars Rover lander is wrapped in airbags to cushion the shock of hitting the martian surface. The airbags will bounce like a beach ball at least 15 times across the landscape before coming to rest. The first bounce may reach as high as 30 meters (100 feet) above the ground. That's the height of three telephone poles stacked one on top of the other! As much as a kilometer of distance (0.6 mile) may be covered from the point of impact on Mars to where the rovers will ultimately come to rest. All of this bouncing and rolling may take as long as ten minutes.

There is a feature on Mars that is so deep, it could swallow Mt. Everest?

The Hellas Impact Basin is an enormous gaping hole in the southern hemisphere Mars. It is 2100 kilometers across (about 1,300 miles) and about nine kilometers deep (six miles). It was probably caused by a violent collision with an asteroid billions of years ago. The powerful impact threw debris as far as 4,000 kilometers (about 2,500 miles) across the surface of the planet. Not much is known about the floor of the great basin. It is so deep that orbiters circling Mars have trouble seeing through the miles of additional atmosphere.

The rovers were not aimed directly toward Mars at launch?

Rockets provide the power to push a spacecraft beyond the grip of Earth's gravity, but rockets by themselves are not meant to put a spacecraft on a precise path to another planet. When Spirit and Opportunity left Earth, they were placed on two paths that would take them to the general vicinity of Mars. In order for the rovers to fly directly to Mars, though, minor adjustments have to be made in their flight plans. Engineers call these adjustments "trajectory correction maneuvers" (TCMs). Tiny rocket thrusters nudge the spacecraft toward a precise path to Mars. Each rover will experience up to six TCMs during their seven-month journey.

The Mars rovers communicate with Earth via a network of dish antennas?

The Deep Space Network transmits and receives Mars rover radio signals through large dish antennas at three sites around the world. These three sites are spaced approximately one-third of the way around the Earth from each other so that one facility is always facing in the right direction as our planet rotates. DSN dish antennas are located in Califonia's Mojave Desert; Madrid, Spain; and Canberra, Australia.

The Mars Exploration Rover lander can automatically right itself?

The MER lander is in the shape of a tetrahedron. Its four sides are called petals. The rover is locked down to one petal — the base petal. When the lander comes to rest on the martian surface, it may not settle with the base petal down. This means the rover can be tipped sideways. How will the lander right itself? The answer lies in its tetrahedral shape. The action of opening the petal the lander rests on (deployment) pushes the lander, and rover, right side up.

People who assemble spacecraft have to wear something called a "bunny suit"?

Before anyone can touch the Mars Rover spacecraft or any of its parts, they must be properly dressed. In this instance, properly dressed means wearing a "bunny suit." No, it's not the type of bunny suit you see at the mall for Easter. It is a stark white outfit that covers you from head to toe with a surgeon's mask, full coveralls, a cap or hood, gloves, and socks pulled up over your shoes. Space hardware must be kept extremely clean. You are extremely dirty -- even if you just stepped out of the bathtub. Your skin, hair and clothing have millions of particles that can flake off and mess up delicate space equipment. A bunny suit is designed to keep you and your germs inside the suit and not on the spacecraft.

The Mars Rover moves as slow as a tortoise?

Martian terrain is rugged. When the Mars Exploration Rover is given a command to travel to an interesting area to study, its path might be littered with rocks and boulders. It must move slowly so that its "brain" can analyze what it sees and pick the best route to travel. The rover will move about the same speed as a Galapagos Tortoise. That's about 79 yards (72 meters) per hour. In other words, over rough terrain, it would take the Mars Rover more than one hour to travel the length of a football field.

Mars has dust devils?

Dust devils are swirling columns of dust that resemble miniature tornadoes. On Earth, they happen in places where the landscape is dry. On Mars, there is plenty of opportunity for a dust devil to form because most of the landscape is very dry. When the sun warms the air closest to the surface of Mars, the air begins to rise and then spin. As it spins, it picks up dust which makes the swirling column become visible. Several dust devils may form at the same location, scurry across the Martian landscape, and leave a jumble of dark lines as evidence of their movements.

In addition to Earth and Mars, there's another body in the Solar System that may contain water?

Europa, a moon of Jupiter, could possibly have liquid water beneath its thick, icy surface due to a process called "tidal heating" that warms the interior of the satellite. Europa is locked in a gravitational tug of war between Jupiter and its other moons. It is pulled in different directions which causes the entire moon to flex. This constant stretching and squeezing produces friction that heats the satellite's interior and could be turning ice into a deep layer of liquid water. For more information about Europa, click here.

Mars has an enormous system of canyons that stretches almost 2,500 miles?

If Valles Marineris (Mariner Valley) was on Earth, it would extend across the entire continental United States. It is up to 400 miles wide and 6 miles deep. That's 6 times deeper than the Grand Canyon! Many researchers feel that Valles Marineris was formed when Mars was very young and its crust stretched and split. Some scientists believe that, at some point in the planet's history, these giant canyons may have been filled with water that flowed from a vast ocean to the north.

Martian dust storms can be incredibly severe?

Dust storms are a natural part of the Martian system. Sometimes such a storm can become so severe that the entire planet is enveloped in dust. This was the case for the Mariner 9 mission back in the 1970s. The spacecraft had to wait more than a month for the dust to settle so that it could finally take images of the planet's surface. In 2001, Mars wrapped itself in dust again for another camera -- the Hubble Space Telescope.

The Mars Exploration Rovers are much larger than the Sojourner rover?

The Sojourner rover on the Pathfinder mission weighed 11 kilograms (about 23 pounds), but the MER weigh approximately 185 kilograms each (about 380 pounds). The two Mars Exploration Rovers weigh more because they are much larger than Sojourner and carry more electronics, bigger solar panels, and all the hardware that makes it possible for them to move long distances across the surface of Mars (the mobility system).

It would be impossible to breathe on Mars?
Martian Atmosphere The Martian atmosphere is very thin and is composed primarily of carbon dioxide with a small amount of nitrogen and argon, as well as a tiny bit of oxygen and water vapor. Compare that to Earth's atmosphere which is full of nitrogen and oxygen. Also, the average temperature on the surface of Mars is -60 Celsius (-76 F), so trying to breathe would not be a pleasant experience.

Mars has seasons?
Trajectory The spin axis of Mars, like Earth, is tilted with respect to the ecliptic plane. The ecliptic plane is an imaginary disk formed by the orbits of almost all of the planets in our solar system. If you draw a perpendicular line from the ecliptic plane, Mars is tilted 25° and Earth 23.5° from that perpendicular line. Mars has enough of a tilt for seasonal changes to occur, and they do. Temperatures increase in the summertime to as much as 20° Celsius near the equator, but in the wintertime it can get very cold. Much of the carbon dioxide in the atmosphere actually freezes and becomes part of the polar ice cap as temperatures drop to -125° Celsius. Because of the difference in the orbits of the two planets, Martian seasons are roughly twice as long as those of Earth.

Two orbiters will help the Mars Exploration Rovers?
Both the Mars Odyssey spacecraft and Mars Global Surveyor are in orbit around Mars. Mars Odyssey arrived in 2001 and MGS has been circling the Red Planet since 1997. Each of these craft carries a suite of science instruments to study Mars, but they will also help the MER mission by serving as communication satellites to relay data from the rovers to Earth.

Mars has two moons named Phobos and Deimos?
Phobos is the Greek word for "fear" and Deimos for "terror." In mythology, Phobos and Deimos are considered to be the sons of Mars, the God of War. Both moons have irregular shapes and are very small. Phobos is about 14 miles wide and Deimos only about 8 miles in diameter. It is not known how they were formed. One theory is that they were asteroids captured by the tug of martian gravity.

Mars is home to the largest known volcano in the Solar System?
Known as Olympus Mons, this shield volcano stretches 27 kilometers up into the Martian sky - that's three times higher than Mt. Everest, the highest mountain on Earth.