News / Science & Technology

    Plummeting US Satellite to Hit Earth Friday

    This conceptual image shows the Upper Atmosphere Research Satellite, launched on September 15, 1991, by the space shuttle Discovery.
    This conceptual image shows the Upper Atmosphere Research Satellite, launched on September 15, 1991, by the space shuttle Discovery.

    Multimedia

    Audio

    NASA launched the Upper Atmosphere Research Satellite (UARS) 20 years ago this month.  And now that bus-sized satellite is plunging toward Earth.

    Mark Matney, an orbital debris scientist at NASA's Johnson Space Center in Texas, says UARS will likely reenter the atmosphere on September 23, 2011.  He says scientists will be able to narrow the time frame as it gets closer.

    As far as where it will crash, Matney says UARS passes over the Earth between 57 degrees north latitude and 57 degrees south latitude.  

    "Everything from Canada down to the tip of South America, and from Siberia down to the tip of Africa and Australia [could be where the satellite lands]," says Matney.  "So, it's quite a bit of land."

    It is also quite a bit of ocean.  Given that more than two-thirds of the planet is covered by water, space debris usually lands with a splash.  

    Still, there is the chance that UARS could land with a thud, although NASA's Matney says this week's satellite reentry is not cause for great concern.

    Take Cover?

    "If you talk about the probability of you getting hit, it's something like one in trillions, so actually the odds of you getting hit is quite small," Matney says.  "So, I don't think anybody needs to be unduly concerned about it."  

    NASA says it has no reports of a person being injured or property being significantly damaged by reentering debris.  But there was an incident in 1997.

    "There actually was a lady in Oklahoma who was hit by a piece of very light debris from a reentering satellite, but it didn't hurt her.  It was a piece of insulation.  She was out jogging, and it hit her," recalls Matney.  "That same reentry dropped two tanks over Texas."

    Matney says debris reentry is a common occurrence, averaging about one piece per day, but that the pieces usually are small.  But he says this will be the first time in 30 years that a U.S. space agency satellite of this size will have crashed back to Earth.  

    Most of UARS is expected to burn up in the atmosphere.

    Computer Modeling

    Even though officials at NASA and the Department of Defense cannot yet provide a precise landing footprint, Matney says the science of figuring out what will land is exacting.  
    "We actually take time to get the original specifications, to get the different parts of the spacecraft, the material types, their shape, their mass," explains Matney.  "And we actually have computer programs that model the dynamics as it begins to heat up and break up and look at the temperatures those pieces reach and whether they reach the melting point of the metal."  

    For instance, he says that because of aluminum's relatively low melting temperature, aluminum objects usually disintegrate before they reach the surface of the Earth.

    NASA expects 26 "potentially hazardous" pieces of UARS to reach the ground, most of them made of titanium, stainless steel or beryllium, which have high melting points.  These pieces of debris include batteries, wheel rims and empty fuel tanks.  UARS debris is expected to range in mass from 0.6 to 158 kilograms.     

    Orbital Debris Management

    NASA's Orbital Debris Program works to reduce the number of large debris pieces in orbit.  One aim is to prevent pieces of space junk from colliding and breaking into smaller pieces as well as to keep active satellites and spacecraft safe.

    NASA's Mark Matney says the space agency took steps in 2005 to decommission the Upper Atmosphere Research Satellite.

    "With what fuel was left on board UARS, we lowered the orbit to a point that we actually shaved 20 years off its lifetime, off its orbit lifetime, to try to remove it from orbit a bit sooner," the scientist explains.

    Finders Keepers?

    NASA officials say people should call their local law enforcement agencies if they find parts of the satellite.  Matney cautions that although the pieces are not toxic, they might have sharp edges.  Even though it is commonly referred to as "space junk," the debris still belongs to the country that owns the craft, in this case, the United States.

    You May Like

    Saudi Arabia’s New Female Politicians in the Other Room 

    Many in Saudi Arabia say elected representatives should share unsegregated spaces; according to a recent survey, more than half the Saudi population, both men and women, prefer to work in a segregated place

    Russia Not ‘Apologetic’ for Syria Airstrikes

    With Moscow criticized for targeting armed opponents of President Assad, Russia’s UN envoy says his country ‘acting in a very transparent manner’

    Pakistan Warns of Islamic State's Growing Reach

    Aftab Sultan, General Director General of Intelligence Bureau (IB), briefed Senate Committee in closed hearing, saying that IS-linked groups have been expanding in Pakistan

    This forum has been closed.
    Comments
         
    There are no comments in this forum. Be first and add one

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Russia's Car Sales Shrink Overall, But Luxury and Economy Models See Growthi
    X
    February 10, 2016 5:54 AM
    Car sales in Russia dropped by more than a third in 2015 because of the country's economic woes. But, at the extreme ends of the car market, luxury vehicles and some economy brands are actually experiencing growth. VOA's Daniel Schearf reports from Moscow.
    Video

    Video Russia's Car Sales Shrink Overall, But Luxury and Economy Models See Growth

    Car sales in Russia dropped by more than a third in 2015 because of the country's economic woes. But, at the extreme ends of the car market, luxury vehicles and some economy brands are actually experiencing growth. VOA's Daniel Schearf reports from Moscow.
    Video

    Video Civil Rights Pioneer Remembers Struggle for Voting Rights

    February is Black History Month in the United States. The annual, month-long national observance pays tribute to important people and events that shaped the history of African Americans. VOA's Chris Simkins reports how one man fought against discrimination to help millions of blacks obtain the right to vote
    Video

    Video Jordanian Theater Group Stages Anti-Terrorism Message

    The lure of the self-styled “Islamic State” has many parents worried about their children who may be susceptible to the organization’s online propaganda. Dozens of Muslim communities in the Middle East are fighting back -- giving young adults alternatives to violence. One group in Jordan is using dramatic expression a send a family message. Mideast Broadcasting Network correspondent Haider Al Abdali shared this report with VOA. It’s narrated by Bronwyn Benito
    Video

    Video Migrant Crisis Fuels Debate Over Britain’s Future in EU

    The migrant crisis in Europe is fueling the debate in Britain ahead of a referendum on staying in the European Union that may be held this year. Prime Minister David Cameron warns that leaving the EU could lead to thousands more migrants arriving in the country. Meanwhile, tension is rising in Calais, France, where thousands of migrants are living in squalid camps. VOA's Henry Ridgwell reports.
    Video

    Video Valentine's Day Stinks for Lebanese Clowns

    This weekend, on Valentine's Day in Lebanon, love is not the only thing in the air. More than half a year after the country's trash crisis began, the stink of uncollected garbage remains on the streets. Step forward "Clown Me In," a group of clowns who use their skills for activism. Before the most romantic day of the year the clowns have released their unusual take on love in Lebanon -- in a bid to keep the pressure up and get the trash off the streets. John Owens reports from Beirut.
    Video

    Video Families Flee Aleppo for Kurdish Regions in Syria

    Not all who flee the fighting in Aleppo are trying to cross the border into Turkey. A VOA reporter caught up with several families heading for Kurdish-held areas of northern Syria.
    Video

    Video Rocky Year Ahead for Nigeria Amid Oil Price Crash

    The global fall in the price of oil has rattled the economies of many petroleum exporters, and Africa’s oil king Nigeria is no exception. As Chris Stein reports from Lagos, analysts are predicting a rough year ahead for the continent’s top producer of crude.
    Video

    Video 'No Means No' Program Targets Sexual Violence in Kenya

    The organizers of an initiative to reduce and stop rape in the informal settlements around Kenya's capital say their program is having marked success. Girls are taking self-defense classes while the boys are learning how to protect the girls and respect them. Lenny Ruvaga reports from Nairobi.
    Video

    Video Chocolate Lovers Get a Sweet History Lesson

    Observed in many countries around the world, Valentine’s Day is sometimes celebrated with chocolate festivals. But at a festival near Washington, the visitors experience a bit more than a sugar rush. They go on a sweet journey through history. VOA’s June Soh takes us to the festival.
    Video

    Video 'Smart' Bandages Could Heal Wounds More Quickly

    Simple bandages are usually seen as the first line of attack in healing small to moderate wounds and burns. But scientists say new synthetic materials with embedded microsensors could turn bandages into a much more valuable tool for emergency physicians. VOA’s George Putic reports.
    Video

    Video Researchers Use 3-D Printer to Produce Transplantable Body Parts

    Human organ transplants have become fairly common around the world in the past few decades. Researchers at various universities are coordinating their efforts to find solutions -- including teams at the University of Pennsylvania and Rice University in Houston that are experimenting with a 3-D printer -- to make blood vessels and other structures for implant. As VOA’s Greg Flakus reports from Houston, they are also using these artificial body parts to seek ways of defeating cancerous tumors.
    Video

    Video Helping the Blind 'See' Great Art

    There are 285 million blind and visually impaired people in the world who are unable to enjoy visual art at a museum. One New York photographer is trying to fix this situation by making tangible copies of the world’s masterpieces. VOA correspondent Victoria Kupchinetsky was there as visually impaired people got a feel for great art. Joy Wagner narrates her report.
    Video

    Video German Artists to Memorialize Refugees With Life Jacket Exhibit

    Sold in every kind of shop in some Turkish port towns, life jackets have become a symbol of the refugee crisis that brought a million people to Europe in 2015.  On the shores of Lesbos, Greece, German artists collect discarded life jackets as they prepare an art installation they plan to display in Germany.  For VOA, Hamada Elrasam has this report from Lesbos, Greece.
    Video

    Video E-readers Help Ease Africa's Book Shortage

    Millions of people in Africa can't read, and there's a chronic shortage of books. A non-profit organization called Worldreader is trying to help change all that one e-reader at a time. VOA’s Deborah Block tells us about a girls' school in Nairobi, Kenya where Worldreader is making a difference.