Curiosity towards Mars
NASA’s most complex and ambitious interplanetary mission lifts off from Florida
PHOTO GALLERY BELOW
By MITCH TRAPHAGEN
KENNEDY SPACE CENTER - For as long as humans have walked the Earth, Mars has been visible in the nighttime sky. It is occasionally the fourth brightest object in the night sky, following the Moon, Venus and Jupiter. Ancient Egyptian astronomers tracked its movement, and astronomers from the Babylonian Empire predicted its course. In the fourth century BC, Aristotle noticed that it traveled behind the Moon, thus demonstrating that it was further away. Nearly 2,000 years passed before people on Earth began to understand just how much farther away it was.
Mars is now as close as it gets at nearly 127 million miles. With a Martian year approximately twice the length of an Earth year, the neighboring planets are only relatively close on their respective orbits around the sun every two years. As the Red Planet has been a focal point of human curiosity over the millennia, it is perhaps appropriate that a Jeep-sized rover named Curiosity departed Kennedy Space Center bound for Mars on November 25 at 10:02 a.m. The mission, known as the Mars Science Laboratory, NASA’s most complex and ambitious interplanetary launch to date, will take approximately eight months to reach the Red Planet, in all traveling more than 350 million miles.
By the nineteenth century, advances in telescope technology had reached the point where astronomers could see the surface features of Mars. In 1877, one astronomer saw features that appeared to be channels on the planet surface. He described those features as canali, something much of the world interpreted as “canals” or non-naturally occurring, Martian-made structures, and thus began a near-assumption on the part of the general populace about life on Mars.
That assumption was turned into panic as recently as 1938, when Orson Welles presented The War of the Worlds as a live news radio broadcast, leading thousands of people to believe that Earth was being invaded by Martians. The idea of non-natural structures on the planet continued until 1965 when NASA’s Mariner 4 became the first spacecraft to successfully reach and photograph Mars. Since then, NASA has landed increasingly complex rovers on Mars with the current rover, named Opportunity, still operational from the 2004 mission. The high-resolution photographs provided by the rovers has dispelled most, but not all, conjecture of man-made objects on the planet (Google “Woman on Mars” for more on recent conjecture).
With the latest rover, Curiosity, due to land in August of 2012, human knowledge of Earth’s closest neighbor is expected to grow by leaps and bounds. Curiosity is not only the largest rover ever launched, but it also contains 10 instruments for scientific study, and even has a rock-zapping laser built onto its “forehead”. The instruments are designed to bore into the planet to determine if Mars was ever hospitable for life, to look for telltale signs in the air, in the texture of rocks, and in mineral and chemical compositions of the soil — both on and beneath the surface.
What it is not designed to do, however, is look for existing life. While Curiosity is highly advanced, the rover may not notice living microbes, if any exist. In fact, finding remnants of ancient life will be difficult. Even here on Earth, NASA describes it as an emerging science.
Due to a similar axis tilt, Mars and Earth both enjoy seasons. On Mars, however, with a much thinner atmosphere than Earth and at greater distance from the sun, those seasons are extreme with temperatures ranging from nearly 200 degrees below zero Fahrenheit during the polar nights to occasionally reaching 80 degrees in the daytime near the equator during the summer months. Surface winds range from zero to 20 miles per hour, with gusts to 90 miles per hour. The planet experiences dust storms that can last for months at a time, sometimes engulfing nearly the entire planet. It is about half the size of Earth but with no oceans, it has roughly the same land mass. The length of a day on Mars is almost identical to that of Earth, but its year is twice as long, as are its individual seasons. Although ice appears on the poles of the planet, the barren surface has little to suggest the presence of life. Billions of years ago, however, things may have been different.
The goal of Curiosity is to search for the basic chemical building blocks of life from inside the Gale Crater, just south of the equator. Curiosity will also assess and characterize the geology of the landing site, investigate planetary processes relating to past habitability (including the role of water) by determining the present state of atmospheric components and assessing its long-term evolution, and investigate surface radiation, including galactic cosmic radiation and solar radiation. All of which will help to guide future robotic missions and even manned missions to Mars.
For the non-scientists among us, the entire expedition will involve some revolutionary and amazing technology, in addition to the laser beam that will be used to analyze the chemistry of rocks. In something never before attempted, Curiosity will be lowered to the surface using a rocket-powered sky crane. The sky crane will lower Curiosity using cables while rockets slow the descent to nearly a hover, gently landing the rover to Mars. It is the stuff of science fiction turned into science reality.
For all of the advances in technology, success at interplanetary exploration remains elusive with roughly two-thirds of all missions to Mars by the world’s various space agencies ending in failure. The Soviet Union was the first to attempt launching probes to Mars in 1960, but NASA was the first to reach the planet successfully in 1965. Russia was also the first to land a spacecraft on the planet with one probe crashing and another failing 15 seconds after landing. The first successful landing was NASA’s Viking program in 1976. In the time since, NASA has held a remarkable track record with rovers performing far beyond the length of their mission requirements and expected life spans, and successfully landing six out of seven missions, but success remains a difficult feat.
On November 9, 2011, a joint mission by the Russian and Chinese space agencies that was designed to land a spacecraft on Phobos, one of the two moons orbiting Mars, and return to Earth with soil samples, has thus far failed to leave Earth’s orbit due to a communications problem. If the problem is not resolved in the coming weeks, the once-in-every two-year window of opportunity to reach Mars will have closed, dooming the probe to a fiery re-entry to Earth.
Prior to its successful launch, even Curiosity experienced problems. The program began in 2003 with the hope of launching in 2009. The project, however, was not complete when that two-year window closed, forcing a delay until Nov. 25, 2011.
With a picture-perfect lift off from Launch Complex 41 at Florida’s Kennedy Space Center, Curiosity was off on a journey of hundreds of millions of miles to answer questions people began asking thousands of years ago. Curiosity is scheduled to reach Mars on August 6, 2012, between 1:00 a.m. and 1:30 a.m. Eastern Time, or roughly 3:00 p.m. in the time zone of the Mars landing site. The mission is scheduled to last approximately one Martian year (98 weeks). Even on Earth, long-range weather forecasting is difficult at best, but NASA has predicted the temperature at the landing site will range from −130 °F to 32 °F. Due to the distance between the planets, messages sent by Curiosity will take 13.8 minutes to reach Earth. Although science has waited thousands of years for the answers Curiosity may provide, those 13 minutes will likely feel like forever to those waiting on the other end.
For more information about Curiosity and the Mars Science Laboratory, visit NASA at www.nasa.gov/msl