MIT tackled Earth's atmosphere to give the moon broadband

Researchers will give more details next month on an experimental laser link

An artist's concept of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft orbiting the moon and preparing to fire its maneuvering thrusters to maintain a safe orbital altitude.

An artist's concept of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft orbiting the moon and preparing to fire its maneuvering thrusters to maintain a safe orbital altitude.

Four transmitting telescopes in the New Mexico desert, each just 6 inches in diameter, can give a satellite orbiting the moon faster Internet access than many U.S. homes get.

The telescopes form the earthbound end of an experimental laser link to demonstrate faster communication with spacecraft and possible future bases on the moon and Mars. Researchers from the Massachusetts Institute of Technology will give details about the system and its performance next month at a conference of The Optical Society.

The Lunar Laser Communication Demonstration (LLCD) kicked off last September with the launch of NASA's LADEE (Lunar Atmosphere and Dust Environment Explorer), a research satellite now orbiting the moon. NASA built a laser communications module into LADEE for use in the high-speed wireless experiment.

LLCD has already proved itself, transmitting data from LADEE to Earth at 622Mbps (bits per second) and in the other direction at 19.44Mbps, according to MIT. It beat the fastest-ever radio communication to the moon by a factor of 4,800.

NASA hopes lasers can speed up communication with missions in space, which use radio to talk to Earth now, and let them send back more data. Laser equipment also weighs less than radio gear, a critical factor given the high cost of lifting any object into space.

The project uses transmitting telescopes at White Sands, New Mexico, to send data as pulses of invisible infrared light. The hard part of reaching the moon by laser is getting through Earth's atmosphere, which can bend light and cause it to fade or drop out on the way to the receiver.

One way the researchers got around that was by using the four separate telescopes. Each sends its beam through a different column of air, where the light-bending effects of the atmosphere are slightly different. That increases the chance that at least one of the beams will reach the receiver on the LADEE.

Test results have been promising, according to MIT, with the 384,633-kilometer optical link providing error-free performance in both darkness and bright sunlight, through partly transparent thin clouds, and through atmospheric turbulence that affected signal power.

One reason it works is that there's plenty of signal power to spare. The transmission power from the Earth antennas totals 40 watts, and less than a billionth of a watt is received on the LADEE. But that's still 10 times the signal needed to communicate without errors, according to MIT. On the craft, a smaller telescope collects the light and focuses it into an optical fiber. After the signal is amplified, it's converted to electrical pulses and into data.

Stephen Lawson covers mobile, storage and networking technologies for The IDG News Service. Follow Stephen on Twitter at @sdlawsonmedia. Stephen's e-mail address is stephen_lawson@idg.com

Join the PC World newsletter!

Error: Please check your email address.

Tags popular sciencetelecommunicationNASANetworkingMassachusetts Institute of Technologyinternet

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Stephen Lawson

IDG News Service
Show Comments

Essentials

Lexar® JumpDrive® S57 USB 3.0 flash drive

Learn more >

Microsoft L5V-00027 Sculpt Ergonomic Keyboard Desktop

Learn more >

Mobile

Lexar® JumpDrive® S45 USB 3.0 flash drive 

Learn more >

Exec

Lexar® Professional 1800x microSDHC™/microSDXC™ UHS-II cards 

Learn more >

Lexar® JumpDrive® C20c USB Type-C flash drive 

Learn more >

Audio-Technica ATH-ANC70 Noise Cancelling Headphones

Learn more >

HD Pan/Tilt Wi-Fi Camera with Night Vision NC450

Learn more >

Budget

Back To Business Guide

Click for more ›

Most Popular Reviews

Latest News Articles

Resources

PCW Evaluation Team

Azadeh Williams

HP OfficeJet Pro 8730

A smarter way to print for busy small business owners, combining speedy printing with scanning and copying, making it easier to produce high quality documents and images at a touch of a button.

Andrew Grant

HP OfficeJet Pro 8730

I've had a multifunction printer in the office going on 10 years now. It was a neat bit of kit back in the day -- print, copy, scan, fax -- when printing over WiFi felt a bit like magic. It’s seen better days though and an upgrade’s well overdue. This HP OfficeJet Pro 8730 looks like it ticks all the same boxes: print, copy, scan, and fax. (Really? Does anyone fax anything any more? I guess it's good to know the facility’s there, just in case.) Printing over WiFi is more-or- less standard these days.

Ed Dawson

HP OfficeJet Pro 8730

As a freelance writer who is always on the go, I like my technology to be both efficient and effective so I can do my job well. The HP OfficeJet Pro 8730 Inkjet Printer ticks all the boxes in terms of form factor, performance and user interface.

Michael Hargreaves

Windows 10 for Business / Dell XPS 13

I’d happily recommend this touchscreen laptop and Windows 10 as a great way to get serious work done at a desk or on the road.

Aysha Strobbe

Windows 10 / HP Spectre x360

Ultimately, I think the Windows 10 environment is excellent for me as it caters for so many different uses. The inclusion of the Xbox app is also great for when you need some downtime too!

Mark Escubio

Windows 10 / Lenovo Yoga 910

For me, the Xbox Play Anywhere is a great new feature as it allows you to play your current Xbox games with higher resolutions and better graphics without forking out extra cash for another copy. Although available titles are still scarce, but I’m sure it will grow in time.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?