News / Science & Technology

NASA Probe Proves Einstein Right

Research leads to groundbreaking technologies

Artist concept of Gravity Probe B orbiting the Earth to measure space-time, a four-dimensional description of the universe including height, width, length, and time.
Artist concept of Gravity Probe B orbiting the Earth to measure space-time, a four-dimensional description of the universe including height, width, length, and time.

Multimedia

Audio
Rosanne Skirble

Albert Einstein was right. The U.S. Space Agency (NASA) released data this week from its Gravity Probe B spacecraft, whose primary mission while in Earth's orbit was to test Einstein’s 1916 Theory of Relativity. While the experiment evolved over decades, the results confirm Einstein’s work on the physical laws of the universe.

A Stanford University scientist first proposed an experiment to test Einstein’s theory in 1959 by rotating gyroscopes in space. Beset by launch delays, budget woes, faulty data and several federal investigations, Gravity Probe B was finally approved and was launched in 1984. The onboard experiment tested two of Einstein’s theories.

The first, explains lead investigator and Stanford University professor Francis Everitt, is the "geodetic effect." "In Einstein’s universe, space and time are warped by gravity. And what happens is the earth distorts the space around it very slightly by its gravity. And it’s 1.1 inches in 25,000 miles (2.75 centimeters in 40,000 kilometers). So it’s a rather modest distortion."

Gravity Probe B prior to launch in 2004
Gravity Probe B prior to launch in 2004
The second of Einstein’s theories that was put to the test is "frame dragging," which is the tendency of a spinning object to pull the fabric of space and time with it as it rotates, a phenomenon Everitt likens to the Earth immersed in a sea of honey.

"You can imagine that the honey would be dragged around with it, hence your pointer in the honey would be dragged around and that’s what happens to a gyroscope.So the earth actually drags space and time around with it."

Gravity Probe B housed several state-of-the-art technologies that did not exist when the Stanford group first conceived their gravity experiments. Among them, Everitt says, were four precision gyroscopes one million times more sensitive than any available back in the 1960s.

"Spheres the size of a Ping-Pong balls go in a quartz housing. We electrically suspend it. We spin it up by means of gas. (We) get it spinning to 5,000 rpm (revolutions per minute), pump out the gas to an extremely high vacuum and there we’ve got our gyroscope."

Once in orbit, the gyroscopes - spinning like a child’s top - were designed to keep Gravity Probe B perfectly aligned with a distant reference star. In confirmation of Einstein’s theories they experienced minute but measurable changes in the direction of their spin as they were pulled by earth’s gravity. 

Over the years, insights gained from Gravity Probe B have spawned a wave of new technologies, including the Global Positioning System, or GPS, a network of earth-orbiting satellites that have become essential for precise navigation on land and sea.

Former NASA manager Rex Geveden says despite the odds that the Gravity Probe B mission would fail, its success is a triumph of the human spirit - and intellect. "It’s a reminder of the sort of greatness that humans can get to when they put their hearts and minds on an objective like this."

Albert Einstein, who died in 1955, never dreamed that his Theory of Relativity would or even could be proved. In his book, The Meaning of Relativity, the famed physicist wrote: "...confirmation of them by laboratory experiments is not to be thought of."

Gravity Probe B lead investigator Francis Everitt adds, "Thanks to NASA we’ve done more than think about them. We’ve measured them."

The findings will appear in a forthcoming issue of the journal Physical Review Letters.

You May Like

Photogallery Americans Celebrate Thanksgiving With Feasts, Festivities

Holiday traditions include turkey dinners, 'turkey trots,' American-style football and New York parade with giant balloons More

Video For Obama, Ferguson Violence is a Personal Issue

With two years left in term, analysts say, president has less to lose by taking conversation on race further More

Video Italian Espresso Expands Into Space

When Italian astronaut Samantha Cristoforetti headed for the ISS, her countrymen worried how she would survive six months drinking only instant coffee More

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.
South Africa Sees Male Circumcision as Way to Reduce HIV Infectionsi
X
November 28, 2014 3:31 PM
South Africa remains plagued by AIDS despite massive government and NGO efforts on prevention and life-sustaining Anti-Retro-Viral programs. But the country has opened up another front to reduce new HIV infections: promoting circumcision. Emilie Iob reports for VOA News from a pioneering circumcision center in Orange Farm, Johannesburg.
Video

Video South Africa Sees Male Circumcision as Way to Reduce HIV Infections

South Africa remains plagued by AIDS despite massive government and NGO efforts on prevention and life-sustaining Anti-Retro-Viral programs. But the country has opened up another front to reduce new HIV infections: promoting circumcision. Emilie Iob reports for VOA News from a pioneering circumcision center in Orange Farm, Johannesburg.
Video

Video To Make A Living, Nairobi Street Vendors Face Legal Hurdles, Physical Violence

The Nairobi City Council has been accused of brutality in dealing with hawkers in the Central Business District - in order to stop them from illegally selling their wares on the streets. Lenny Ruvaga has more for VOA News from the Kenyan capital.
Video

Video For Obama, Ferguson Violence is a Personal Issue

Throughout the crisis in Ferguson, Missouri, President Barack Obama has urged calm, restraint and respect for the rule of law. But the events in Ferguson have prompted him to call — more openly than he has before — for profound changes to end the racism and distrust that he believes still exists between whites and blacks in the United States. VOA White House correspondent Luis Ramirez reports.
Video

Video Online Magazine Gets Kids Discussing Big Questions

Teen culture in America is often criticized for being superficial. But an online magazine has been encouraging some teenagers to explore deeper issues, and rewarding their efforts. VOA religion reporter Jerome Socolovsky went to this year’s Kidspirit awards ceremony in New York.
Video

Video US Community Kicks Off Thanksgiving With Parade

Thursday is Thanksgiving in the United States, a holiday whose roots go back to the country's earliest days as a British colony. One way Americans celebrate the occasion is with parades. Anush Avetisyan takes us to one such event on the day before Thanksgiving near Washington, where a community's diversity is on display. Joy Wagner narrates
Video

Video Aung San Suu Kyi: Myanmar Opposition to Keep Pushing for Constitutional Change

Myanmar opposition leader Aung San Suu Kyi says she and her supporters will continue pushing to amend a constitutional clause that bars her from running for president next year. VOA's Than Lwin Htun reports from the capital Naypyitaw in this report narrated by Colin Lovett.
Video

Video Mali Attempts to Shut Down Ebola Transmission Chain

Senegal and Nigeria were able to stop small Ebola outbreaks by closely monitoring those who had contact with the sick person and quickly isolating anyone with symptoms. Mali is now scrambling to do the same. VOA’s Anne Look reports from Mali on what the country is doing to shut down the chain of transmission.
Video

Video Ukraine Marks Anniversary of Deadly 1930s Famine

During a commemoration for millions who died of starvation in Ukraine in the early 1930s, President Petro Poroshenko lashed out at Soviet-era totalitarianism for causing the deaths and accused today’s Russian-backed rebels in the east of using similar tactics. VOA’s Daniel Shearf reports from Kyiv.
Video

Video Hong Kong Protests at a Crossroads

New public opinion polls in Hong Kong indicate declining support for pro-democracy demonstrations after weeks of street protests. VOA’s Bill Ide in Guangzhou and Pros Laput in Hong Kong spoke with protesters and observers about whether demonstrators have been too aggressive in pushing for change.
Video

Video US Immigration Relief Imminent for Mixed-Status Families

Tens of thousands of undocumented immigrants in the Washington, D.C., area may benefit from a controversial presidential order announced this week. It's not a path to citizenship, as some activists hoped. But it will allow more immigrants who arrived as children or who have citizen children, to avoid deportation and work legally. VOA's Victoria Macchi talks with one young man who benefited from an earlier presidential order, and whose parents may now benefit after years of living in fear.
Video

Video New Skateboard Defies Gravity

A futuristic dream only a couple of decades ago, the hoverboard – a skateboard that floats above the ground - has finally been made possible. While still not ready for mass production, it promises to become a cool mode of transport... at least over some surfaces. VOA’s George Putic reports.
Video

Video Falling Gas Prices Impact US Oil Extraction

With the price of oil now less than $80 a barrel, motorists throughout the United States are benefiting from gas prices below $3 a gallon. But as VOA’s Kane Farabaugh reports, the decreasing price of petroleum has a downside for the hydraulic fracturing industry in the United States.

All About America

AppleAndroid