News / Science & Technology

    NASA: Shielding, New Propulsion Technologies Needed for Manned Mission to Mars

    Artist’s rendition of astronauts on Mars. (NASA)Artist’s rendition of astronauts on Mars. (NASA)
    x
    Artist’s rendition of astronauts on Mars. (NASA)
    Artist’s rendition of astronauts on Mars. (NASA)
    Suzanne Presto
    The U.S. space agency is relying on findings from an ongoing, unmanned mission to Mars as it shapes plans for a human mission to that planet in the mid-2030s.

    As NASA's Mars Science Laboratory sped toward the Red Planet in 2011 and 2012, an instrument called the Radiation Assessment Detector measured radiation levels that a space crew could experience during the long journey.   

    New findings published in the journal Science indicate a trip to Mars could subject space travelers to more radiation than NASA allows. Longstanding research shows that exposure to radiation increases a person's risk of developing cancer.

    Propulsion

    Scientists say one way to reduce radiation exposure is to develop new propulsion technologies that would shorten the time it takes to get to Mars, thereby reducing the time a person is subjected to radiation in deep space.

    NASA's deputy director of advanced exploration systems, Chris Moore, says engineers are working on advanced systems that could cut a one-way trip to Mars down from about 250 days to 180 days.

    "To get really fast trip times and cut down on the radiation exposure, we would probably need nuclear thermal propulsion, and we're working with the U.S. Department of Energy now to look at various types of fuel elements for these rockets," said Moore. "But it's a long-range technology development activity, and it will probably be many years before that is ready."  

    Moore emphasized that nuclear thermal propulsion is part of the current plan to get humans to Mars.   

    Shielding

    During the journey through deep space, astronauts would be exposed to two types of radiation that pose potential risks. Galactic cosmic rays are caused by supernova explosions and other high-energy events outside the solar system. Solar energetic particles are linked to solar flares and coronal mass ejections from the sun.

    Eddie Semones, the space flight radiation health officer at NASA's Johnson Space Center in Houston, says this requires a two-pronged mitigation approach.

    "We need to get there [to Mars] faster to reduce the impact of the galactic cosmic rays, but we need to have shielding, local shielding, on board to eliminate the effects of solar particle events, so it's hand-in-hand," he said.       

    Semones says deployable shields are effective at reducing the effects of solar particle events because those events are low energy. But he says in order to reduce the effect of high-energy galactic cosmic rays, shields would have to be meters thick -- too thick for a spacecraft to launch successfully from Earth.

    Looking to the Future

    The Curiosity rover's Radiation Assessment Detector continued to take measurements after it landed on the Martian surface in August.

    NASA says the medical community is using the radiation data to develop exposure limits for deep space explorers.

    You May Like

    Chechen Suspected in Istanbul Attack, but Questions Remain

    Turkish sources say North Caucasus militants involved in bombing at Ataturk airport, but name of at least one alleged attacker raises doubts

    With Johnson Out, Can a New ‘Margaret Thatcher’ Save Britain?

    Contest to replace David Cameron as Britain’s prime minister started in earnest Thursday with top candidates outlining strategy to deal with Brexit fallout

    US Finds Progress Slow Against Human Trafficking in Africa

    Africa continues to be a major source and destination for human trafficking of all kinds -- from forced labor to sexual slavery, says State Department report

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Clinton Leads Trump, But Many Voters Don't Like Eitheri
    X
    Jim Malone
    June 29, 2016 6:16 PM
    In the U.S. presidential race, most recent polls show Democrat Hillary Clinton with a steady lead over Republican Donald Trump as both presumptive party nominees prepare for their party conventions next month. Trump’s disapproval ratings have risen in some recent surveys, but Clinton also suffers from high negative ratings, suggesting both candidates have a lot of work to do to improve their images before the November election. VOA National correspondent Jim Malone has more from Washington.
    Video

    Video Clinton Leads Trump, But Many Voters Don't Like Either

    In the U.S. presidential race, most recent polls show Democrat Hillary Clinton with a steady lead over Republican Donald Trump as both presumptive party nominees prepare for their party conventions next month. Trump’s disapproval ratings have risen in some recent surveys, but Clinton also suffers from high negative ratings, suggesting both candidates have a lot of work to do to improve their images before the November election. VOA National correspondent Jim Malone has more from Washington.
    Video

    Video Slow Rebuilding Amid Boko Haram Destruction in Nigeria’s Northeast

    Military operations have chased Boko Haram out of towns and cities in Nigeria’s northeast since early last year. But it is only recently that people have begun returning to their homes in Adamawa state, near the border with Cameroon, to try to rebuild their lives. For VOA, Chris Stein traveled to the area and has this report.
    Video

    Video New US Ambassador to Somalia Faces Heavy Challenges

    The new U.S. envoy to Somalia, who was sworn into office Monday, will be the first American ambassador to that nation in 25 years. He will take up his post as Somalia faces a number of crucial issues, including insecurity, an upcoming election, and the potential closure of the Dadaab refugee camp in Kenya. VOA’s Jill Craig asked Somalis living in Kenya’s capital city Nairobi how they feel about the U.S. finally installing a new ambassador.
    Video

    Video At National Zoo, Captivating Animal Sculptures Illustrate Tragedy of Ocean Pollution

    The National Zoo in Washington, D.C., is home to about 1,800 animals, representing 300 species. But throughout the summer, visitors can also see other kinds of creatures there. They are larger-than-life animal sculptures that speak volumes about a global issue — the massive plastic pollution in our oceans. VOA's June Soh takes us to the zoo's special exhibit, called Washed Ashore: Art to Save the Sea.
    Video

    Video Baghdad Bikers Defy War with a Roar

    Baghdad is a city of contradictions. War is a constant. Explosions and kidnappings are part of daily life. But the Iraqi capital remains a thriving city, even if a little beat up. VOA's Sharon Behn reports on how some in Baghdad are defying the stereotype of a nation at war by pursuing a lifestyle known for its iconic symbols of rebellion: motorbikes, leather jackets and roaring engines.
    Video

    Video Melting Pot of Immigrants Working to Restore US Capitol Dome

    The American Iron Works company is one of the firms working to renovate the iconic U.S. Capitol Dome. The company employs immigrants of many different cultural and national backgrounds. VOA’s Arman Tarjimanyan has more.
    Video

    Video Testing Bamboo as Building Material

    For thousands of years various species of bamboo - one of the world's most versatile plants - have been used for diverse purposes ranging from food and medicine to textiles and construction. But its use on a large scale is hampered because it's not manufactured to specific standards but grown in the ground. A University of Pittsburgh professor is on track to changing that. VOA’s George Putic reports.
    Video

    Video Orphanage in Iraqi City Houses Kids Who Lost their Parents to Attacks by IS

    An orphanage in Iraqi Kurdistan has become home to scores of Yazidi children who lost their parents after Islamic State militants took over Sinjar in Iraq’s Nineveh Province in 2014. Iraqi Kurdish forces backed by the U.S. airstrikes have since recaptured Sinjar but the need for the care provided by the orphanage continues. VOA’s Kawa Omar filed this report narrated by Rob Raffaele.
    Video

    Video Re-Opening Old Wounds in a Bullet-Riddled Cultural Landmark

    A cultural landmark before Lebanon’s civil war transformed it into a nest of snipers, Beirut’s ‘Yellow House’ is once again set to play a crucial role in the city.  Built in a neo-Ottoman style in the 1920s, in September it is set to be re-opened as a ‘memory museum’ - its bullet-riddled walls and bunkered positions overlooking the city’s notorious ‘Green Line’ maintained for posterity. John Owens reports from Beirut.
    Video

    Video Brexit Resounds in US Presidential Contest

    Britain’s decision to leave the European Union is resounding in America’s presidential race. As VOA’s Michael Bowman reports, Republican presumptive nominee Donald Trump sees Britain’s move as an affirmation of his campaign’s core messages, while Democrat Hillary Clinton sees the episode as further evidence that Trump is unfit to be president.
    Video

    Video NASA Juno Spacecraft, Nearing Jupiter, to Shed Light on Gas Giant

    After a five-year journey, the spacecraft Juno is nearing its destination, the giant planet Jupiter, where it will enter orbit and start sending data back July 4th. As Mike O'Sullivan reports from Pasadena, California, the craft will pierce the veil of Jupiter's dense cloud cover to reveal its mysteries.
    Video

    Video Orlando Shooting Changes Debate on Gun Control

    It’s been nearly two weeks since the largest mass shooting ever in the United States. Despite public calls for tighter gun control laws, Congress is at an impasse. Democratic lawmakers resorted to a 1960s civil rights tactic to portray their frustration. VOA’s Carolyn Presutti explains how the Orlando, Florida shooting is changing the debate.

    Special Report

    Adrift The Invisible African Diaspora