Incredible Technology: How Robotic Spacecraft Spy On Mars from Orbit

[Buster's Uncle]

Incredible Technology: How Robotic Spacecraft Spy On Mars from Orbit
SPACE.com
By Mike Wall, Senior Writer  November 18, 2013 10:02 AM






NASA plans to launch its next Mars orbiter today (Nov. 18), kicking off a mission that differs markedly from the space agency's many previous Red Planet efforts.

Unlike the nine other orbiters that NASA has blasted toward Mars over the last 40 years, the MAVEN spacecraft — short for Mars Atmosphere and Volatile Evolution — will set its sights on the thin shell of air swirling above the Red Planet's dry and frigid surface. The spacecraft will lift off at 1:28 p.m. EST (1828 GMT) and you can watch the launch live on SPACE.com via NASA TV, beginning at 11 a.m. EST (1600 GMT).

"We're an atmospheric monitoring mission, whereas all the orbiters that come before us have really been surface-mapping, surface-observation-type missions," Guy Beutelschies, MAVEN project manager at Lockheed Martin Space Systems, which built the spacecraft, told reporters Friday (Nov. 15).



An illustration of NASA's powerful Mars Reconnaissance Orbiter.


A mysterious planet comes into focus

NASA has been sending probes toward Mars since November 1964, when the agency launched the Mariner 3 spacecraft on an attempted Red Planet flyby. That mission failed, but Mariner 4, which blasted off just three weeks later, managed to beam home 21 up-close photos of Mars — the first pictures of another planet ever returned to Earth from deep space.

NASA's first attempt at a Mars orbiter also failed when Mariner 8 crashed into the Atlantic Ocean shortly after liftoff in May 1971. But the space agency made history with Mariner 9, which became the first probe ever to orbit another planet when it arrived at Mars in November 1971.



This artist's concept shows the MAVEN spacecraft in orbit around the Red Planet


Mariner 9 sent more than 7,300 images back to Earth, allowing researchers to create a global map of the Martian surface. These photos painted the Red Planet in an entirely new light, revealing huge volcanoes, giant canyons and what appeared to be the remnants of ancient riverbeds. The probe also took the first up-close pictures of Mars' two tiny moons, Phobos and Deimos, according to NASA officials.

Next up were the twin Viking orbiters, which launched a few weeks apart in 1975. Viking 1 and 2 flew with landers designed to search for signs of Mars life, so part of the orbiters' mission involved supporting these surface craft. But the two orbiters returned a wealth of scientific data in their own right, improving researchers' understanding of the Red Planet's topography and finding evidence that large amounts of water flowed across the Red Planet's surface long ago.

"Volcanoes, lava plains, immense canyons, cratered areas, wind-formed features and evidence of surface water are apparent in the orbiter images," NASA officials write in a summary of the Viking mission. "The planet appears to be divisible into two main regions, northern low plains and southern cratered highlands."

The Viking landers, meanwhile, found no solid evidence of Martian organisms, though researchers are still arguing about the results of their experiments today.



The Mariner 9 spacecraft.


Taking a closer look

A long lull followed the Viking mission; NASA launched its next Red Planet explorer, an orbiter called Mars Observer, in 1992. The probe failed just before reaching Mars — a fate shared by the agency's Mars Climate Orbiter, which blasted off in December 1998.

But sandwiched between these two ill-fated missions was the Mars Global Surveyor (MGS), which studied the Red Planet for more than nine years after arriving in orbit in September 1997.

The probe used five different instruments to make a host of discoveries about the Red Planet. For example, MGS before-and-after images of two different gullies suggest that liquid water may have flowed on Mars within the last decade or so, NASA officials have said.

Further, the orbiter's laser altimeter helped scientists create the best-ever topographic map of the Red Planet, and readings from its magnetometer indicate that Mars once had a global magnetic field, just like Earth. (Earth has retained its field, but Mars has not.)

NASA's next Red Planet orbiter, Mars Odyssey, eventually wrested the longevity record away from MGS. Odyssey arrived in orbit around Mars in October 2001 and continues to study the Red Planet to this day.

Using its three main science instruments, Odyssey has mapped the global distribution of many minerals and chemical elements across the Martian surface, found evidence of large amounts of buried water ice near the planet's poles and measured the radiation environment in low Mars orbit, which could help NASA plan out future manned missions to the Red Planet.



Viking 1 and 2, both of which landed in 1976, returned the first useable data from the planet's surface


The probe also serves as a vital communications link, relaying data gathered by NASA's Mars rovers back home to Earth. (The agency currently has two rovers exploring the Red Planet's surface — Opportunity, which landed in January 2004, and Curiosity, which touched down in August 2012.)

NASA's next Mars-circling craft, the Mars Reconnaissance Orbiter, has also enjoyed a long and successful mission.

MRO has been studying the Red Planet with six different instruments since arriving in orbit in March 2006. This gear allows the probe to analyze surface minerals, hunt for underground water, monitor Martian weather and take spectacular up-close images of the planet's surface.

MRO's HiRISE camera (short for High Resolution Imaging Science Experiment) can distinguish Martian objects as small as a dinner table, allowing researchers to study the planet's surface features more completely than ever before. This capability has also helped NASA select suitable landing sites for surface craft, such as the Phoenix lander and Curiosity rover.

Like Odyssey, MRO also serves a vital relay function, helping send information from Opportunity and Curiosity back to the robots' handlers on Earth.


MAVEN joins the ranks

Some of the above missions have gathered data about the Martian atmosphere, which was thick long ago when the Red Planet was relatively warm and wet but has been largely lost to space over the eons. However, the Red Planet's air was not their primary focus.

"There's a heavy emphasis earlier, in other missions, on what's happening on the surface of Mars — what happened to the water and understanding topography and so on," David Mitchell, MAVEN project manager at NASA's Goddard Space Flight Center in Greenbelt, Md., said during the Nov. 15 press conference.

MAVEN's chief goal, on the other hand, is figuring out what happened to the Red Planet's atmosphere. The probe will use its eight science instruments to study the solar wind and Mars' upper atmosphere, discerning its composition and how quickly its volatile compounds are escaping into space.

"We collectively, as a team, came up with instrumentation that really goes after, ultimately, the question that we're on, which is the climate — what's happened in the history of Mars?" Mitchell said. "Why did it go from a wetter, Earth-like environment with a thicker atmosphere to where it is today?"


Not just NASA

Not all Mars-orbiting spacecraft have flown American flags over the years, of course. The Soviet Union had a very active Mars program in the 1960s and '70s and succeeded in placing three spacecraft in orbit around the Red Planet between 1971 and 1974.

These probes — known as Mars 2, Mars 3 and Mars 5 — returned a total of 120 images of the Red Planet and gathered data about Mars' gravity and magnetic fields. (Many Soviet/Russian Mars efforts have failed over the years, most recently 2011's Phobos-Grunt mission to Phobos, which never made it out of Earth orbit.)

Europe has a robotic ambassador circling the Red Planet as well. The European Space Agency's Mars Express probe continues to image and study the surface of the Red Planet and gather data about the Martian atmosphere today, nearly 10 years after arriving in orbit around Mars.

On Nov. 5, India launched its first interplanetary probe, the Mars Orbiter Mission, on a mission to probe the Red Planet. Like MAVEN, the Indian Mars probe will arrive at Mars in September 2014 if all goes well.


http://news.yahoo.com/incredible-technology-robotic-spacecraft-spy-mars-orbit-150259958.html

[Buster's Uncle]

MAVEN takes off: what you need to know about NASA’s new mission to Mars
The latest venture to the red planet will investigate Mars' mysterious atmosphere
By Alexander Thompson on November 18, 2013 10:32 am






The idea of humans one day colonizing Mars is a tantalizing one, but there are some obvious obstacles to our long-term residency on the red planet. Chief among them? The absence of water. Research has established that Mars used to have liquid water on its surface, but now it's a dry, dusty, inhospitable desert.

Today, NASA will launch a new mission — one that cost $671 million and has been in development for 10 years — to determine what happened to the water on Mars. The Curiosity rover has given us some insight into the conundrum, such as confirming that Mars used to host liquid water by spotting visible stream beds. Curiosity also established, via chemical analysis, that water still exists in Martian soil. It could be that some of the missing water has been absorbed into the soil or simply frozen. But scientists are intrigued by another possibility — water on Mars may have evaporated and been lost to space.


Water on Mars may have evaporated and been lost to space

The agency will now investigate that exact hypothesis with a new probe, called MAVEN, which will orbit around our red neighbor. MAVEN stands for Mars Atmosphere and Volatile EvolutioN, and as the name implies, MAVEN's mission is to characterize the Martian atmosphere. Researchers will use the data gathered by MAVEN to construct a history of the climate on Mars and paint a picture of how Mars lost its water.

Of course, this is no simple task. "It keeps you up at night," says Janet Luhmann, the deputy principal investigator of the MAVEN project. Luhmann is excited about how this mission will further our knowledge of Mars, but the exuberance at what she hopes MAVEN will reveal is tempered by the costs of bringing the project to fruition. "It's an investment financially. It's an investment in human energy and effort, and you want to make sure it succeeds, so it's stressful."

Weather permitting, MAVEN will launch today at 1:28PM ET from Cape Canaveral in Florida. So what does it take in order to peer into the distant past of the Martian atmosphere?


The mission





The MAVEN mission is an exercise in collaboration, and the instruments onboard reflect that fact. The devices necessary for the venture have been provided by three different groups — the University of California, Berkeley; the University of Colorado; and NASA's Goddard Space Flight Center. And each of these groups will use data provided by the equipment to glean insights into long-lost Martian water.

An Atlas V rocket will blast the nearly 3-ton MAVEN probe into space. Once MAVEN's solar arrays are fully extended, the craft will be as long as a school bus. When it arrives on Mars, it won't travel in a traditional circular orbit that would keep MAVEN at a constant distance from the planet. Instead, MAVEN will orbit in an elliptical path that will alternately bring it close to and far from the planet. At its furthest point from Mars, MAVEN will be 3,900 miles away in order to better measure the effects of the sun. MAVEN's elliptical orbit will also bring it within 93 miles of the planet to characterize the upper atmosphere. In addition to these regular close sweeps, MAVEN will perform five "deep dives" where it will dip even further — 78 miles from the surface — to profile the atmosphere at a lower altitude.


A holistic picture of the Martian atmosphere

The probe contains a suite of instruments that will give researchers a holistic picture of the Martian atmosphere, how it changes, and the role the sun has played in removing the planet's atmosphere: scientists think there's an important, but complex, relationship between the loss of water on Mars and other atmospheric gases and solar activity. MAVEN's instruments will characterize the gases and ions that are leaving the planet, and determine the extent to which these losses are due to energetic particles in solar wind — essentially a spew of material emitted by the sun — kicking the gases out of the atmosphere.

The Earth is largely protected from these events due to strong magnetic fields from its iron core, but Mars has a much weaker magnetic field, making the planet more susceptible to the effects of solar storms. Researchers speculate that when the Martian atmosphere is hit with solar wind, some of its gases are removed. That drier atmosphere then creates a driving force for water to evaporate. If scientists can track the evolution of the atmosphere, and corresponding solar activity, over the yearlong mission, they might be able to project the state of the atmosphere back in time to test the hypothesis as an explanation for Mars' loss of water.

That tracking remains a ways off: it will take about 10 months for the probe to arrive at the red planet, and researchers hope to start gathering useful information around November of 2014. But the mission could have taken much longer to get moving: the recent US government shutdown threatened MAVEN's launch window, meaning NASA would have had to wait for the planets to align, so to speak, to select another departure date.


The payoff


Mars today, shown at left, is dry and inhospitable. But as indicated in the right, the planet may once have been a much more watery place.


The MAVEN mission is expected to change how we think of and interact with Mars, both in the near and long term. Having another satellite orbiting the planet will immediately aid other Mars-oriented research. MAVEN contains a relay, for instance, that will increase the data-transfer capabilities of missions like Curiosity and the InSight lander, expected to launch in 2016 with plans to probe for seismic activity.

This research will also aid investigators as they continue to study exoplanets. Teams have been scouting for planets that orbit in the not-too-hot, not-too-cold region around our sun called the habitable zone, in hopes of finding planets that may harbor life. However, while there are three planets around our sun considered to be in this zone, only Earth — and not Venus or Mars — seems to harbor life. Learning more from Mars will help scientists understand why, and offer them new clues as they hunt for life across the universe.

MAVEN might also help us figure out how to one day colonize the Red Planet. When asked about a far-off future where we might terraform the thin Martian atmosphere to be breathable, Luhmann speculates that Mars' atmospheric history will make that impractical. Instead, humans may live in biospheres and produce a local atmosphere within them. "I think a limited, controlled, enclosed environment would be the way you would have to go," Luhmann says. "Doing the whole planet is science fiction."

For those keen to track MAVEN's progress, NASA will be posting to Twitter, allowing anyone to follow the project as a spectator. And scientists are hoping to see more active citizen involvement too: the data gathered by MAVEN will be released to the public through their Planetary Data System portal. "We're going to make unique measurements and have a unique dataset that will be part of the treasure trove of the science of humankind," Luhmann says. "The rewards are potentially huge. The rewards are ultimately that you're going to increase human understanding [of the universe] forever."


http://www.theverge.com/2013/11/18/5117312/maven-nasa-mission-to-mars-what-to-know