NASA plans to test laser communications link with upcoming lunar mission

An upcoming NASA mission will test a new laser communications system that could one day deliver high-definition 3D video signals from Mars and beyond.

The lunar laser communications demonstration will be part of the agency's Lunar Atmosphere and Dust Environment Explorer (LADEE) mission, which is scheduled to launch on Sept. 6. The LADEE spacecraft will orbit the moon and collect information on the lunar atmosphere—technically an exosphere—for around 100 days. A laser communications module is built into the satellite.

"NASA has a need for faster download speeds for data from space and that grows everyday, just like it does for the rest of us at home and also from work," said Don Cornwell, mission manager for the lunar laser communications demonstration. He was speaking at a televised NASA news conference on Thursday.

"We'd like to be able to send high-resolution images and movies and 3D even from satellites that not only orbit the Earth but also from probes that will go to the moon and beyond. Communicating with radio waves has served us well for the last 50 years but we now have the technology to use light waves to communicate more data," he said.

NASA Ames / Dana Berry

Here's how the system will work: When the satellite is in orbit around the moon and visible from Earth, one of three ground stations will shoot a laser towards its approximate location. The laser beam from Earth will scan a patch of sky and should illuminate the spacecraft at some point. When that happens, the spacecraft will begin transmitting its own laser towards the ground station and the two will lock on to each other. Once that happens, communications can begin.

The ground stations are at White Sands in New Mexico, at a NASA Jet Propulsion Laboratory site in Wrightwood, California, and a European Space Agency site in Tenerife, Spain.

The technology should allow an upstream data rate, from the Earth to the spacecraft, of around 20Mbps and a much faster downstream rate of 622Mbps. Home Internet speeds typically run from several megabits per second to several tens of megabits per second.

That's roughly six times the speed that's currently possible with radio-based transmission, said Cornwell. As a bonus, the laser communications equipment also weighs half that of a radio transmitter and costs about a quarter less, he said.

(See a video version of this story on YouTube.)

Cornwell said he hopes the test is the first step in demonstrating the usefulness of laser communications and building confidence in its use in future missions, including those that go deeper into space. He said laser communications systems get more attractive compared to radio the further the spacecraft travels from Earth because the communications beam can be better focused.

"As you go further out into the solar system, it's a much more efficient way to get high bandwidth at low power," said John Grunsfeld, NASA's associate administrator for science and a former astronaut.

"We've already been having discussions about how you could do laser communications on a rover on the surface of Mars," he said, referencing a NASA mission to Mars planned for 2020.

"This is just the beginning of what will be replacing some of the radio frequency communication in the future," said Grunsfeld. "I think there is no question that as we send humans further out into the solar system, certainly to Mars, that if we want to have high-def 3D video, we're going to have laser communications sending that information back."

Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service.
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NASA plans to test laser communications link with upcoming lunar mission

An upcoming NASA mission will test a new laser communications system that could one day deliver high-definition 3D video signals from Mars and beyond.

The lunar laser communications demonstration will be part of the agency's Lunar Atmosphere and Dust Environment Explorer (LADEE) mission, which is scheduled to launch on Sept. 6. The LADEE spacecraft will orbit the moon and collect information on the lunar atmosphere—technically an exosphere—for around 100 days. A laser communications module is built into the satellite.

"NASA has a need for faster download speeds for data from space and that grows everyday, just like it does for the rest of us at home and also from work," said Don Cornwell, mission manager for the lunar laser communications demonstration. He was speaking at a televised NASA news conference on Thursday.

"We'd like to be able to send high-resolution images and movies and 3D even from satellites that not only orbit the Earth but also from probes that will go to the moon and beyond. Communicating with radio waves has served us well for the last 50 years but we now have the technology to use light waves to communicate more data," he said.

NASA Ames / Dana Berry

Here's how the system will work: When the satellite is in orbit around the moon and visible from Earth, one of three ground stations will shoot a laser towards its approximate location. The laser beam from Earth will scan a patch of sky and should illuminate the spacecraft at some point. When that happens, the spacecraft will begin transmitting its own laser towards the ground station and the two will lock on to each other. Once that happens, communications can begin.

The ground stations are at White Sands in New Mexico, at a NASA Jet Propulsion Laboratory site in Wrightwood, California, and a European Space Agency site in Tenerife, Spain.

The technology should allow an upstream data rate, from the Earth to the spacecraft, of around 20Mbps and a much faster downstream rate of 622Mbps. Home Internet speeds typically run from several megabits per second to several tens of megabits per second.

That's roughly six times the speed that's currently possible with radio-based transmission, said Cornwell. As a bonus, the laser communications equipment also weighs half that of a radio transmitter and costs about a quarter less, he said.

(See a video version of this story on YouTube.)

Cornwell said he hopes the test is the first step in demonstrating the usefulness of laser communications and building confidence in its use in future missions, including those that go deeper into space. He said laser communications systems get more attractive compared to radio the further the spacecraft travels from Earth because the communications beam can be better focused.

"As you go further out into the solar system, it's a much more efficient way to get high bandwidth at low power," said John Grunsfeld, NASA's associate administrator for science and a former astronaut.

"We've already been having discussions about how you could do laser communications on a rover on the surface of Mars," he said, referencing a NASA mission to Mars planned for 2020.

"This is just the beginning of what will be replacing some of the radio frequency communication in the future," said Grunsfeld. "I think there is no question that as we send humans further out into the solar system, certainly to Mars, that if we want to have high-def 3D video, we're going to have laser communications sending that information back."

Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service.
More by Martyn Williams, IDG News Service

View the original article here

NSA collected thousands of domestic communications in 2011, court document shows

The National Security Agency was acquiring thousands of digital communications from Americans as of 2011, according to a declassified document from the Foreign Intelligence Surveillance Court.

The glimpse of the NSA's surveillance on people in the U.S. was revealed Wednesday in an 86-page court assessment of the constitutionality of agency's data collection methods. It was released by the Office of the Director of National Intelligence.

The 2011 assessment was based on NSA's own review of what the document refers to as "a statistically representative sample" drawn from the intelligence agency's collection of upstream data. "Upstream data" refers to Internet communications, such as email, as they transit, rather than to acquisitions directly from Internet service providers, the court document said.

The review revealed that NSA acquired roughly 2,000 to 10,000 "multi-communication transactions," or MCTs, each year that contain at least one wholly domestic communication. An MCT refers to the capture of multiple different communications at once, such as emails within a single webmail service, one staff member at the Electronic Frontier Foundation said. EFF has been fighting for the federal court to release the review for over a year.

The document also said that the NSA had been acquiring more than 250 million Internet communications in total each year.

The numbers help to shed new light on the scope of government surveillance into people's online communications in the name of national security.

Kurt Opsahl, senior staff attorney with the Electronic Frontier Foundation, called the figures "very significant."

"It shows that the NSA was misusing its authority for years and scanning the content of communications to do so," he said in an email.

The review also revealed a deception. Until NSA's manual review, "the government asserted that NSA had never found a wholly domestic communication in its upstream collection," the court opinion said.

The court expressed reservations throughout the document over the constitutionality of the NSA's data collection methods. Specifically, the procedures that the NSA used to target and minimize its data collection efforts among only foreigners who are of interest to national security issues "are inconsistent with the requirements of the Fourth Amendment," the document said.

The court also lamented a lack of information about the NSA's methods in its review. "The practical implications of NSA's acquisition of Internet transactions through its upstream collection for the Court's statutory and Fourth Amendment analyses are difficult to assess," the document said.

The document was released in response to a Freedom of Information Act lawsuit from the Electronic Frontier Foundation. The digital rights group called its release a victory, partly because it will help to encourage a public debate on the issue of government surveillance.

"Disclosing this opinion -- and releasing enough of it so that citizens and advocates can intelligently debate the constitutional violation that occurred -- is a critical step in ensuring that an informed debate takes place," EFF staff attorney Mark Rumold said in a statement.

The document's release comes just weeks after President Obama announced some sweeping reforms designed to limit data collection by the NSA under the Patriot Act.

Much of the issue of government surveillance has been pushed into the public consciousness following leaks made by former NSA contractor Edward Snowden.

Zach Miners covers social networking, search and general technology news for IDG News Service. Follow Zach on Twitter at @zachminers. Zach's e-mail address is zach_miners@idg.com

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