Tag Archives: Space

Scientists test warning system as asteroid flies by

Scientists test warning system as asteroid flies by

FRANKFURT (Reuters) – An asteroid the size of a school bus flew remarkably near Earth on Thursday, providing scientists with an opportunity to test the warning systems that would kick in if a space collision was coming.

Asteroid 2012 TC4 came close — passing Earth at a distance of only around 44,000 km (27,000 miles), which is nothing in Universe terms.

There was no actual risk of a hit, although the asteroid did come well inside the orbit of the Moon and that of some human-made satellites.

“Basically, we pretended that this is a ‘critical’ object with a high risk of impacting Earth … and exercised our communication channels and used telescopes and radar systems for observations,” Detlef Koschny of European Space Agency said in a blog post on the agency’s website.

The results were mixed.

Koschny said one big radar system in Puerto Rico did not work due to damage from Hurricane Maria but that another U.S. based radar system was used instead.

“This is exactly why we do this exercise – to not be surprised by these things,” he said.

Radar images showed the asteroid was about 10 to 12 meters (yards) wide, roughly the size of an asteroid that exploded over Chelyabinsk, Russia in 2013, leaving more than 1,000 people injured by flying glass and debris.

Koschny said the ESA now needed to update its predictions for how close 2012 TC4 will come to Earth on its next flyby, which has so far been forecast for 2079.

(Reporting by Maria Sheahan; Editing by Jeremy Gaunt)

Solar eclipse presents first major test of power grid in renewable era

FILE PHOTO -- An array of solar panels are seen in Oakland, California, U.S. on December 4, 2016. REUTERS/Lucy Nicholson/File Photo

By Ruthy Munoz

HOUSTON (Reuters) – As Monday’s total solar eclipse sweeps from Oregon to South Carolina, U.S. electric power and grid operators will be glued to their monitoring systems in what for them represents the biggest test of the renewable energy era.

Utilities and grid operators have been planning for the event for years, calculating the timing and drop in output from solar, running simulations of the potential impact on demand, and lining up standby power sources. It promises a critical test of their ability to manage a sizeable swing in renewable power.

Solar energy now accounts for more than 42,600 megawatts (MW), about 5 percent of the U.S.’s peak demand, up from 5 MW in 2000, according to the North American Electric Reliability Council (NERC), a group formed to improve the nation’s power system in the wake of a 1964 blackout. When the next eclipse comes to the United States in 2024, solar will account for 14 percent of the nation’s power, estimates NERC.

For utilities and solar farms, the eclipse represents an opportunity to see how well prepared their systems are to respond to rapid swings in an era where variable energy sources such as solar and wind are climbing in scale and importance.

Power companies view Monday’s event as a “test bed” on how power systems can manage a major change in supply, said John Moura, director of reliability assessment and system analysis at the North American Electric Reliability Corp.

“It has been tested before, just not at this magnitude,” adds Steven Greenlee, a spokesman for the California Independent System Operator (CISO), which controls routing power in the nation’s most populous state.

CISO estimates that at the peak of the eclipse, the state’s normal solar output of about 8,800 MW will be reduced to 3,100 MW and then surge to more than 9,000 MW when the sun returns.

CISO’s preparation includes studying how German utilities dealt with a 2015 eclipse in that country. Its review prompted the grid overseer to add an additional 200 MW to its normal 250 MW power reserves.

“We’ve calculated that during the eclipse, that solar will ramp off at about 70 MW per minute,” said Greenlee. “And then we’ll see the solar rolling back at about 90 MW per minute or more.”

Power utilities say the focus will be on managing a rapid drop off and accommodate the solar surge post the eclipse. Utility executives say they do not expect any interruption in service, but are prepared to ask customers to pare usage if a problem arises.”We want to assure our customers that we have secured enough resources to meet their energy needs, even with significantly less solar generation on hand,” said Caroline Winn, chief operating officer at utility San Diego Gas & Electric Co.

In the Eastern United States, utilities will have more time to watch the results of their Western counterparts. PJM Interconnection, which coordinates electricity transmission among 13 states from Michigan to North Carolina, says non-solar sources such as hydro and fossil fuel can easily supplant the 400 MW to 2,500 MW solar loss, depending on the cloud cover.

For small-scale solar providers, the eclipse is a drop in the revenue bucket. Ron Strom, a North Carolina real estate developer, sells the power from a 58 kilovolt system atop a commercial property in Chapel Hill to Duke Energy.

“The event may cost me eighteen cents or thereabouts if my panels don’t produce solar for three hours,” said Strom.

(Additional reporting by Nichola Groom in Los Angeles; editing by Diane Craft)

Millions of Americans to gaze upon Monday’s once-in-a-lifetime eclipse

Millions of Americans to gaze upon Monday's once-in-a-lifetime eclipse

By Steve Gorman

(Reuters) – Twilight will fall at midday on Monday, stars will glimmer and birds will roost in an eerie stillness as millions of Americans and visitors witness the first total solar eclipse to traverse the United States from coast to coast in 99 years.

The sight of the moon’s shadow passing directly in front of the sun, blotting out all but the halo-like solar corona, may draw the largest live audience for a celestial event in human history. When those watching via broadcast and online media are factored into the mix, the spectacle will likely smash records.

“It will certainly be the most observed total eclipse in history,” astronomer Rick Fienberg of the American Astronomical Society (AAS) said last week.

The eclipse begins its cross-country trajectory over the Pacific Coast of Oregon in late morning. It will reach South Carolina’s Atlantic shore some 90 minutes later.

The total eclipse of the sun is considered one of the most spell-binding phenomena in nature but it rarely occurs over a wide swath of land, let alone one of the world’s most heavily populated countries at the height of summer.

In terms of audience potential, it is hard to top the United States, with its mobile and affluent population, even though the direct path is mostly over rural areas, towns and small cities. The largest is Nashville, Tennessee, a city of 609,000 residents.

Even so the advent of social media and inexpensive high-tech optics have boosted public awareness, assuring what many U.S. experts predict will be unprecedented viewership for the so-called “Great American Eclipse.”

Some might take issue with that prediction, citing a solar eclipse visible over parts of India, Nepal, Bangladesh and central China in July 2009. National Geographic estimated 30 million people in Shanghai and Hangzhou alone were in its path that day.

On Monday, the deepest part of the shadow, or umbra, cast by the moon will fall over a 70-mile-wide (113-km-wide), 2,500-mile-long (4,000-km-long) “path of totality” traversing 14 states. The 12 million people who live there can view the eclipse at its fullest merely by walking outside and looking up, weather permitting.

LIVESTREAMING AND PRICE-GOUGING

Some 200 million Americans reside within a day’s drive of the totality zone, and as many as 7 million, experts say, are expected to converge on towns and campgrounds along the narrow corridor for the event. Many are attending multi-day festivals featuring music, yoga and astronomy lectures.

Millions more could potentially watch in real time as the eclipse is captured by video cameras mounted on 50 high-altitude balloons and streamed online in a joint project between NASA and Montana State University. A partial eclipse will appear throughout North America.

Adding further to the excitement is the wide availability of affordable solar-safe sunglasses produced by the millions and selling so fast that suppliers were running out of stock.

The owner of one leading manufacturer reported price gouging by second-hand dealers who were buying up large supplies in and reselling them over the internet at a huge mark-up.

Not all the hoopla will unfold on dry land. Welsh pop singer Bonnie Tyler is slated to perform her 1983s hit single “Total Eclipse of the Heart” aboard a cruise liner as the vessel sails into the path of totality from Florida on Monday.

Back on the ground, forest rangers, police and city managers in the total eclipse zone are bracing for a crush of travelers they fear will cause epic traffic jams and heighten wildfire hazards.

“Imagine 20 Woodstock festivals occurring simultaneously across the nation,” Michael Zeiler, an AAS advisory panel member wrote on his website, GreatAmericanEclipse.com, referring to the famously chaotic 1969 outdoor rock extravaganza in upstate New York.

Zeiler, an avowed “eclipse chaser” who made the 650-mile (1,046 km) drive from his New Mexico home to Wyoming for a choice view, said South Carolina is likely to see the greatest influx as the destination state closest to the entire U.S. Eastern seaboard.

Monday’s event will be the first total solar eclipse spanning the entire continental United States since 1918 and the first visible anywhere in the Lower 48 states in 38 years.

The next one over North America is due in just seven years, in April 2024.

(Reporting by Steve Gorman in Los Angeles; Editing by Frank McGurty and Sandra Maler)

China tests self-sustaining space station in Beijing

A volunteer checks on plants inside a simulated space cabin in which he temporarily lives with others as a part of the scientistic Lunar Palace 365 Project, at Beihang University in Beijing, China

By Natalie Thomas

BEIJING (Reuters) – Sealed behind the steel doors of two bunkers in a Beijing suburb, university students are trying to find out how it feels to live in a space station on another planet, recycling everything from plant cuttings to urine.

They are part of a project aimed at creating a self-sustaining ecosystem that provides everything humans need to survive.

Four students from Beijing University of Aeronautics and Astronautics entered the Lunar Palace-1 on Sunday with the aim of living self-sufficiently for 200 days.

A volunteer answers reporters' questions from inside a simulated space cabin in which she temporarily lives with others as a part of the scientistic Lunar Palace 365 Project, at Beihang University in Beijing, China

A volunteer answers reporters’ questions from inside a simulated space cabin in which she temporarily lives with others as a part of the scientistic Lunar Palace 365 Project, at Beihang University in Beijing, China July 9, 2017. REUTERS/Damir Sagolj

They say they are happy to act as human guinea-pigs if it means getting closer to their dream of becoming astronauts.

“I’ll get so much out of this,” Liu Guanghui, a PhD student, who entered the bunker on Sunday, said. “It’s truly a different life experience.”

President Xi Jinping wants China to become a global power in space exploration, with plans to send the first probe to the dark side of the moon by 2018 and to put astronauts on the moon by 2036. The Lunar Palace 365 experiment may allow them to stay there for extended periods.

For Liu Hong, a professor at Beijing University of Aeronautics and Astronautics and the project’s principal architect, said everything needed for human survival had been carefully calculated.

“We’ve designed it so the oxygen (produced by plants at the station) is exactly enough to satisfy the humans, the animals, and the organisms that break down the waste materials,” she said.

But satisfying physical needs is only one part of the experiment, Liu said. Charting the mental impact of confinement in a small space for such a long time is equally crucial.

“They can become a bit depressed,” Liu said. “If you spend a long time in this type of environment it can create some psychological problems.”

A member of staff is seen in front of screens showing inside of a simulated space cabin in which volunteers temporarily live as a part of the scientistic Lunar Palace 365 Project, at Beihang University in Beijing, China

A member of staff is seen in front of screens showing inside of a simulated space cabin in which volunteers temporarily live as a part of the scientistic Lunar Palace 365 Project, at Beihang University in Beijing, China July 9, 2017. REUTERS/Damir Sagolj

Liu Hui, a student leader who participated an initial 60-day experiment at Lunar Palace-1 that finished on Sunday, said that she sometimes “felt a bit low” after a day’s work.

The project’s support team has found mapping out a specific set of daily tasks for the students is one way that helps them to remain happy.

But the 200-day group will also be tested to see how they react to living a for period of time without sunlight. The project’s team declined to elaborate.

“We did this experiment with animals… so we want to see how much impact it will have on people,” Liu, the professor, said.

 

(Reporting By Natalie Thomas. Editing by Jane Merriman)

 

SpaceX successfully launches first recycled rocket booster

A recycled SpaceX Falcon 9 rocket soars toward space above a Virgin Airlines passenger jet, which had just departed Orlando International Airport, in Orlando, Florida, March 30, 2017. The launch marked the first time ever that a rocket was reused for spaceflight. REUTERS/Gregg Newton

By Irene Klotz

CAPE CANAVERAL, Fla. (Reuters) – A SpaceX Falcon 9 rocket recovered at sea from its maiden flight last year blasted off again from Florida on Thursday in the first successful launch of a recycled orbital-class booster, then capped the feat with another return landing on an ocean platform.

The unprecedented twin achievements of re-launching a used rocket and salvaging the vehicle yet again were hailed by billionaire SpaceX founder Elon Musk as a revolutionary step in his quest to slash launch costs and shorten intervals between space shots.

“This is a huge day,” Musk told reporters after the launch. “My mind’s blown.”

It took Space Exploration Technologies Corp, as the California-based company is formally known, 15 years to demonstrate that a rocket typically discarded in the ocean after a single flight could be recovered and reused.

The SpaceX chief executive said his next goal is to turn the booster around for relaunch in 24 hours, a milestone he said could be accomplished before the end of the year.

“The potential is there for (an) over 100-fold reduction in the cost of access to space. If we can achieve that, it means humanity can become a space-faring civilization and be out there among the stars. This is what we want for the future,” he said.

The Falcon 9 booster, which previously flew in April 2016, lifted off from the Kennedy Space Center at 6:27 p.m. EDT (2227 GMT) to put a communications satellite into orbit for Luxembourg-based SES SA <SESFg.LU>.

The booster’s main section then separated from the rest of the rocket and flew itself back to a landing pad in the Atlantic, where it successfully touched down for its second at-sea return.

“We made a little bit of history today … opened the door into a whole new era of spaceflight,” said Martin Halliwell the chief technology officer for SES, who joined Musk at the news conference.

SpaceX landed an orbital rocket after launch for the first time in December 2015, a feat it has now repeated eight times. The Falcon 9 booster launched for the company’s 33rd mission on Thursday was also the first to make a successful return landing in the ocean.

By reusing rockets, SpaceX aims to eventually cut its costs by about 30 percent, the company has said. It lists the cost of a Falcon 9 ride at $62 million but has not yet announced a price for flying on a recycled rocket.

Not all the savings will be passed on to SpaceX customers, some of whom were awaiting the outcome of Thursday’s flight before agreeing to fly on a used booster, Musk said.

The company spent at least $1 billion developing the technology to land and refly its rockets and aims to recoup its investment in the next year or so, Musk said.

The boosters are expected to be able to fly 10 times with no refurbishment and about 100 times with moderate reconditioning, though the one launched Thursday will be donated to the Cape Canaveral Spaceport for display, Musk said.

Proving the concept works is crucial to SpaceX, which is moving on from an accident in September that damaged another Florida site.

SpaceX also is working on a passenger spaceship, with two unidentified tourists signed up for a future trip around the moon. The company’s long-term goal under Musk is to establish a colony on Mars and ferry people and cargo back and forth between the planets.

On Thursday, the rocket’s second-stage, which is not recovered, continued firing to carry SES-10 into an initial egg-shaped orbit high above Earth, which it will provide television and other communications services to Latin America.

SES received a discount for joining the inaugural run, Halliwell told reporters, but he declined to say how much. The latest flight brings to 65 the number of SES satellites in orbit, with nine more slated for launch this year.

(Reporting by Irene Klotz; Editing by James Dalgleish and Lisa Shumaker)

Meteor lights up the night sky over Illinois and Wisconsin

National Weather Service tweet about meteor

(Reuters) – (This February 6th story has been refiled to correct location of Lisle to west of Chicago in paragraph three.)

A meteor plummeted in a fireball over Lake Michigan early on Monday, lighting up the night sky in bright blue just before scattering over the lake in many pieces, according to a police video and an expert’s description.

Lisle, Illinois, police officer Jim Dexter recorded the meteor’s descent on the dash camera of his patrol car at 1:25 a.m.

Aside from Lisle, which is less than 30 miles (48 km) west of Chicago, and other parts of Illinois; witnesses reported seeing the meteor from Wisconsin, Michigan and as far away as New York state and the Canadian province of Ontario, according to a description on the website of the American Meteor Society.

The meteor’s fiery descent is likely to rank as one of the most spectacular events of its kind anywhere in the world this year, Mike Hankey, operations manager for the society, said by telephone.

The meteor broke apart into pieces of rock and metallic dust that descended in a cloud onto Lake Michigan, Hankey said. No one is reported to have been injured by debris, he said.

(Reporting by Alex Dobuzinskis in Los Angeles; Editing by Sandra Maler)

NASA’s Juno spacecraft loops into orbit around Jupiter

Jupiter

By Irene Klotz

CAPE CANAVERAL, Fla. (Reuters) – NASA’s Juno spacecraft capped a five-year journey to Jupiter late Monday with a do-or-die engine burn to sling itself into orbit, setting the stage for a 20-month dance around the biggest planet in the solar system to learn how and where it formed.

“We’re there. We’re in orbit. We conquered Jupiter,” lead mission scientist Scott Bolton, with the Southwest Research Institute in San Antonio, told reporters on Tuesday. “Now the fun begins.”

Juno will spend the next three months getting into position to begin studying what lies beneath Jupiter’s thick clouds and mapping the planet’s gargantuan magnetic fields.

Flying in egg-shaped orbits, each one lasting 14 days, Juno also will look for evidence that Jupiter has a dense inner core and measure how much water is in the atmosphere, a key yardstick for figuring out how far away from the sun the gas giant formed.

Jupiter’s origins, in turn, affected the development and position of the rest of the planets, including Earth and its fortuitous location conducive to the evolution of life.

“The question I’ve had my whole life that I’m hoping we get an answer to is ‘How’d we get here?’ That’s really pretty fundamental to me,” Bolton said.

Jupiter orbits five times farther from the sun than Earth, but it may have started out elsewhere and migrated, jostling its smaller sibling planets as it moved.

Jupiter’s immense gravity also diverts many asteroids and comets from potentially catastrophic collisions with Earth and the rest of the inner solar system.

Launched from Florida nearly five years ago, Juno needed to be precisely positioned, ignite its main engine at exactly the right time and keep it firing for 35 minutes to become only the second spacecraft to orbit Jupiter.

If anything had gone even slightly awry, Juno would have sailed helplessly past Jupiter, unable to complete a $1 billion mission.

The risky maneuver began as planned at 11:18 p.m. EDT as Juno soared through the vacuum of space at more than 160,000 mph (257,500 kph).

NASA expects Juno to be in position for its first close-up images of Jupiter on Aug. 27, the same day its science instruments are turned on for a test run.

Only one other spacecraft, Galileo, has ever circled Jupiter, which is itself orbited by 67 known moons. Bolton said Juno is likely to discover even more.

Seven other U.S. space probes have sailed past the gas giant on brief reconnaissance missions before heading elsewhere in the solar system.

The risks to the spacecraft are not over. Juno will fly in highly elliptical orbits that will pass within 3,000 miles (4,800 km) of the tops of Jupiter’s clouds and inside the planet’s powerful radiation belts.

Juno’s computers and sensitive science instruments are housed in a 400-pound (180-kg) titanium vault for protection. But during its 37 orbits around Jupiter, Juno will be exposed to the equivalent of 100 million dental X-rays, said Bill McAlpine, radiation control manager for the mission.

The spacecraft, built by Lockheed Martin, is expected to last for 20 months. On its final orbit, Juno will dive into Jupiter’s atmosphere, where it will be crushed and vaporized.

Like Galileo, which circled Jupiter for eight years before crashing into the planet in 2003, Juno’s demise is designed to prevent any hitchhiking microbes from Earth from inadvertently contaminating Jupiter’s ocean-bearing moon Europa, a target of future study for extraterrestrial life.

(Editing by Kim Coghill and Andrew Heavens)

Human flights to Mars still at least 15 years off: ESA head

Monitors in the ESOC

By Maria Sheahan and Ashutosh Pandey

DARMSTADT, Germany (Reuters) – Dreaming of a trip to Mars? You’ll have to wait at least 15 years for the technology to be developed, the head of the European Space Agency (ESA) said, putting doubt on claims that the journey could happen sooner.

“If there was enough money then we could possibly do it earlier but there is not as much now as the Apollo program had,” ESA Director-General Jan Woerner said, referring to the U.S. project which landed the first people on the moon.

Woerner says a permanent human settlement on the moon, where 3D printers could be used to turn moon rock into essential items needed for the two-year trip to Mars, would be a major step toward the red planet.

U.S. space agency NASA hopes to send astronauts to Mars in the mid-2030s and businessman Elon Musk, head of electric car maker Tesla Motors, says he plans to put unmanned spacecraft on Mars from as early as 2018 and have humans there by 2030.

The ESA’s Woerner said it would take longer.

A spacecraft sent to Mars would need rockets and fuel powerful enough to lift back off for the return trip and the humans would need protection from unprecedented physical and mental challenges as well as deep-space radiation.

Woerner would like to see a cluster of research laboratories on the moon, at what he calls a “moon village”, to replace the International Space Station when its lifetime ends and to test technologies needed to make the trip to Mars.

That could be funded and operated by a collection of private and public bodies from around the world, he said in an interview at the ESA’s Operations Centre.

“There are various companies and public agencies asking to join the club now, so they want to do different things, resource mining, in situ research, tourism and that kind of stuff. There is a big community interested,” he told Reuters.

“The moon village is a pit stop on the way to Mars,” Woerner said, adding that new 3D printing technology could be used to build material and structures out of rocks and dust, doing away with the cost of transporting everything needed for a mission.

“To test how to use lunar material to build some structures, not only houses, but also for a telescope or whatever, will teach us also how to do it on Mars,” he said.

The ESA, working with Russia, in March sent a spacecraft on a seven-month journey as part of the agency’s ExoMars mission, which will use an atmospheric probe to sniff out signs of life on Mars and deploy a lander to test technologies needed for a rover scheduled to follow in 2020.

Woerner said Europe was looking at ways to lower the cost of launches but did not plan to copy Elon Musk’s SpaceX, which is trying to develop relatively cheap, reusable launch vehicles.

“We should not copy. To follow and copy does not bring you into the lead. We are looking for totally different approaches,” Woerner said, adding the ESA was examining all manner of new technologies, including air-breathing engines that do not need to tap into oxygen from a spacecraft’s tank.

(Additional reporting by Reuters TV; Editing by Robin Pomeroy)

NASA to set fire in space for science, safety

The Orbital ATK Cygnus spacecraft departs the International Space Station

By Irene Klotz

CAPE CANAVERAL, Fla. (Reuters) – An unmanned cargo ship pulled away from the International Space Station on Tuesday to stage the first of three planned NASA experiments on how big fires grow in space, an important test for astronaut safety.

Previous experiments in space were limited to the incineration of samples no bigger than an index card, said David Urban, lead researcher for the Spacecraft Fire Experiment, or Saffire.

“We tried for years to find a vehicle and a circumstance where this would work and initially we’d get a ‘not on my spacecraft’ reaction,” Urban said during a NASA TV interview.

The National Aeronautics and Space Administration ultimately settled on using an Orbital ATK Cygnus cargo ship, which is designed to burn up in the atmosphere after it departs the space station.

The Cygnus, which departed the space station on Tuesday, was launched from Earth in March with more than 7,000 pounds (3,200 kg) of food, supplies and science experiments for the station, a research laboratory that flies about 250 miles (400 km) above the planet.

The cargo included Saffire, a module containing a 38-inch by 19-inch (97 cm by 49 cm) cotton-and-fiberglass material sample that will be set on fire after Cygnus reaches a safe distance from the station.

The experiment will begin with hot wires igniting the sample. Air flowing through ducts will fan the fire, which is expected to last about 20 minutes.

“One of the big questions is how big will the flame get?” Urban said.

Fire behaves differently outside of Earth’s atmosphere, so scientists want to test whether microgravity will limit flames and what materials will burn.

The question is not academic. In February 1997, an oxygen-generating canister aboard the Russian Mir space station erupted into a searing flame, blocking the crew’s path to an emergency escape ship.

The crew fought the fire with foam extinguishers and water and it eventually burned itself out, leaving a thick residue of soot.

The Saffire experiment will be the largest fire set in space since the accidental blaze on Mir.

Onboard sensors will record temperature, oxygen and carbon dioxide levels, while two cameras snap pictures. The data and images will be relayed to ground control teams over the next four to six days. NASA plans two more Saffire experiments aboard future Cygnus spacecraft.

(Reporting by Irene Klotz; Editing by Fiona Ortiz and Steve Orlofsky)

North Korea satellite tumbling in orbit again, U.S. sources say

WASHINGTON (Reuters) – North Korea’s recently launched satellite is once again tumbling in orbit, after stabilizing briefly, according to a U.S. official and other sources.

The satellite update came as a key congressional watchdog agency said the U.S. military had not demonstrated its ability to protect the United States against a possible North Korea missile attack.

Earlier this month North Korea launched what it said was an earth observation satellite but what the country’s neighbors and the United States called a missile test. It was earlier believed to have achieved stable orbit but not to have transmitted data back to Earth.

The U.S. official, and two other sources with knowledge of the issue, said they are less concerned about the function of the satellite than with the technology involved in launching it. They added that the launch was clearly intended to demonstrate North Korea’s ability to launch an intercontinental ballistic missile.

The U.S. Government Accountability Office, the research arm of Congress, highlighted concerns about missile attacks from North Korea in a report released on Wednesday.

“GMD flight testing, to date, was insufficient to demonstrate that an operationally useful defense capability exists,” the GAO said. GMD is an acronym for a ground-based missile defense system.

The report said that the missile defense system, or the Ground-based Midcourse Defense, had only demonstrated “a partial capability against small numbers of simple ballistic missile threats.”

Ken Todorov, former deputy director of the Missile Defense Agency, said the organization faced a difficult balancing act in meeting the needs of the U.S. military and operating with limited resources for testing.

Last month the Missile Defense Agency conducted a successful test of the ground-based U.S. missile defense system managed by Boeing Co aimed at demonstrating the effectiveness of a redesigned “kill vehicle” built by Raytheon Co.

The test purposely did not include an intercept by a ground-based interceptor but was designed to demonstrate the ability of new “divert thrusters” that were developed by Raytheon to maneuver the warhead.

The report said that while there were benefits in the way the agency was acquiring the kill vehicle, challenges remained.

It added that the Pentagon’s goal to reach 44 ground-based missile defense systems by the end of 2017 was based on a “highly optimistic, aggressive schedule” leading to “high-risk acquisition practices.”

(Reporting by Idrees Ali and Andrea Shalal; Editing by Andrew Hay)