http://www.esa.int/Our_Activities/Operations/Moon_mission_beams_laser_data_to_ESA_station

ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

…

“We’ve already received data at up to 40 Mbit/s – several times faster than a typical home broadband connection.”

…

What the receiver on earth sees with an infrared camera:

———————

Wowzers, the NBN has arrived on the moon already. That’s 100 times faster than my “broadband”.

Kingy said:

http://www.esa.int/Our_Activities/Operations/Moon_mission_beams_laser_data_to_ESA_station

ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

…

“We’ve already received data at up to 40 Mbit/s – several times faster than a typical home broadband connection.”

…

What the receiver on earth sees with an infrared camera:

———————

Wowzers, the NBN has arrived on the moon already. That’s 100 times faster than my “broadband”.

Yes, but the NBN does it cheaper

…just kidding.

Kingy said:

ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

What am I missing?

I thought radio waves travelled at the speed of light, so how can a laser deliver data faster that a radio wave?

sibeen said:

Kingy said:

http://www.esa.int/Our_Activities/Operations/Moon_mission_beams_laser_data_to_ESA_station

ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

…

“We’ve already received data at up to 40 Mbit/s – several times faster than a typical home broadband connection.”

…

What the receiver on earth sees with an infrared camera:

———————

Wowzers, the NBN has arrived on the moon already. That’s 100 times faster than my “broadband”.

Yes, but the NBN does it cheaper

…just kidding.

Mr Abbott is trying to get a small asteroid in close orbit to the moon to put his roadside node on, and then he will run copper wire to the moon surface…

than a radio wave

AussieDJ said:

Kingy said:

ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

What am I missing?

I thought radio waves travelled at the speed of light, so how can a laser deliver data faster that a radio wave?

Bandwidth.

Stealth said:

AussieDJ said:

Kingy said:

ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

What am I missing?

I thought radio waves travelled at the speed of light, so how can a laser deliver data faster than a radio wave?

Bandwidth.

So a laser can carry more data than a radio wave, then?

AussieDJ said:

Stealth said:

AussieDJ said:

What am I missing?

I thought radio waves travelled at the speed of light, so how can a laser deliver data faster than a radio wave?

Bandwidth.

So a laser can carry more data than a radio wave, then?

Frequency. This pic might help explain it.

AussieDJ said:

Stealth said:

AussieDJ said:

What am I missing?

I thought radio waves travelled at the speed of light, so how can a laser deliver data faster than a radio wave?

Bandwidth.

So a laser can carry more data than a radio wave, then?

Pretty much. The frequency of the EM wave is related to the amount of data that can be transmitted.

The frequency of the EM wave is related to the amount of data that can be transmitted.

better the other way around….bandwidth is dependent on frequency.

AussieDJ said:

Kingy said:

ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

What am I missing?

I thought radio waves travelled at the speed of light, so how can a laser deliver data faster that a radio wave?

As a analogy, thik of sending messages by morse code. With a bad connection the dots and dashes have to be sent slower so the person at the other end can read tem without making mistakes, say a dash might be drawn out for a couple of seconds. But with a clear line they can send signals through as fast as the receiver can write. Obviously in the latter scenario they are going to transfer much more data across, even though the signals themselves are travelling at the same speed.

One relevant question would be that if there are clouds overhead, do the signals get through(unlikely), and do they have a radio dialup backup?

the laser is near infra-red so clouds shouldn’t pose too much of a problem and i would imagine that the frequency was choosen with this in mind.

JudgeMental said:

the laser is near infra-red so clouds shouldn’t pose too much of a problem and i would imagine that the frequency was choosen with this in mind.

According to the chart I posted earlier, (insert comment about everything you read on the ‘net being true???), that frequency only barely penetrates the atmosphere. With my very limited knowledge on the subject, I would expect that clouds would make things worse.

However, I have been wrong before, and my assumptions on the physics of photons have about as much credibility as the fact checker in Star Wars.

if they have trouble penetrating the atmosphere even without clouds then why would they have chosen that frequency? would make no sense. the ground station on tenerife is 2400m above sea level, if it is the optical one.

http://coolcosmos.ipac.caltech.edu/cosmic_classroom/ask_astronomer/faq/radiation.shtml

http://www.iac.es/eno.php?op1=3&op2=6&lang=en&id=7

the OGS on Tenerife.

http://en.wikipedia.org/wiki/Infrared_window

However, I have been wrong before, and my assumptions on the physics of photons have about as much credibility as the fact checker in Star Wars.
——————————-
The fact checkers credibilty relies on whether or not the laws of physics are infact the same throughout the universe. But regardless of the outcome of this posit, you have definitely been wrong many, many times before.

Stealth said:

However, I have been wrong before, and my assumptions on the physics of photons have about as much credibility as the fact checker in Star Wars.
——————————-
The fact checkers credibilty relies on whether or not the laws of physics are infact the same throughout the universe. But regardless of the outcome of this posit, you have definitely been wrong many, many times before.

People who can’t even spell credibility shouldn’t throw stones. :P

Excellent info, JudgeMental. Thanks.

http://esc.gsfc.nasa.gov/267/271/335.html

http://esc.gsfc.nasa.gov/267/271.html

The Lunar Laser Communication Demonstration (LLCD)

http://dspace.mit.edu/openaccess-disseminate/1721.1/61673

The Lunar Laser Communications Demonstration (LLCD)

pdf of the system.

infra red would be absorbed by water in the atmosphere

as far as I knew the yanks were using blue/green lasers to talk to subs some 20m in the water from space

With a bad connection the dots and dashes have to be sent slower so the person at the other end can read tem without making mistakes, say a dash might be drawn out for a couple of seconds.
—————————————————————

Yeah but no but no.

What other end?

Where we see them…

Where we think they might be now…

Or wherever we guess they could be when the beam may or may not get there.