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kaguya takes images of lunar surface

*headdesk*

Of all of the times for me to forget the download rate from Mars Global Surveyor.
 
For Galileo, the directional antenna has a theoretical max rate of 134kbits / second (not bytes) That's about 1 640x480 picture per minute. TV Video is right at 30 frames per second of uncompressed data.

So, ignoring command and control signals, actual science traffic, reoirinting the spacecraft to shoot the images, and spacecraft telemetry taking up their portion of the data pipe, the technology is limited to video at 1/1800th of realtime.

This figure also assumes 100% availability of NASA's Deep Space Network of dishes, unlikely to happen since the DSN is always in demand for things like Mars Rovers, Mars Observers, Voyager probes, Etc, etc, etc.

Another factor to consider: Speed at which things happen in space. Distances are vast, and it would take a long time to notice much difference in images coming from a camera aimed at a body thousands of kilometers away. Video would be incredibly boring.
 
For clarification, the Galileo spacecraft I cited for my second example was sent to Jupiter and its moons.

The Cassini spacecraft, even further out at Saturn, is currently sending back data at a not quite so blazing 948 bits (no bloody K) per second. That's 5.4 minutes or so for a single 640x480 monochrome image.

Bandwidth is in part a function of distance using current technology, and the moon is close enough that video works.

In summary:

Inner planets and their satellites; usually OK fine for real time video.

Belt and beyond; don't start the popcorn, you'll be dissapointed.

AG
 
Alpha_Geek said:
For clarification, the Galileo spacecraft I cited for my second example was sent to Jupiter and its moons.

The Cassini spacecraft, even further out at Saturn, is currently sending back data at a not quite so blazing 948 bits (no bloody K) per second. That's 5.4 minutes or so for a single 640x480 monochrome image.

Bandwidth is in part a function of distance using current technology, and the moon is close enough that video works.

In summary:

Inner planets and their satellites; usually OK fine for real time video.

Belt and beyond; don't start the popcorn, you'll be dissapointed.

AG

Although I don't doubt that real time video feed is not possible, I think you are forgetting compression of image which plays a major part in long range transmission like this.
 
SamuraiBlue said:
Although I don't doubt that real time video feed is not possible, I think you are forgetting compression of image which plays a major part in long range transmission like this.

Depends on what they're doing with the imagery. While compressed data may save bandwidth, it's not the actual data that the sensors got, therefore the science could be suspect for the nit-picking academic. It'd be just fine for us gawking taxpayers though. :)

AG
 
Alpha_Geek said:

I don't think you understand the difference in the amount of data or the tiny amount of bandwidth that is available when a transmission source is that distant, moving at a high rate of speed, oh, yeah, and your recieving antennas can only face the source for a limited amount of time due to that whole spinning earth thing...

Well technically speaking a camera could've been installed on MRO and we could've gotten a low grade quality "live video" from Mars but other than the cool factor it wouldn't have benefited the mission in any scientific way. MRO's telecom system is vastly superior over the systems of previous Mars probes like the MGS. It can typically send data to Earth at a rate between 0.5 Mbps to 4 Mbps as opposed to the kbps expected in previous mars missions. Its also currently being used to demonstrated DSN's Ka-band capability which if successful (by no mean a guarantee since Ka-band signals are affected by weather and pointing errors much more) a migration to it from X-band could lift the maximum bandwidth ceilng to a much higher level.
 
I'm not really looking for live video... I'm looking for shots and angles of the moon (as seen here) and other planets and bodies. It is images and videos that inspire the imagination of the unobsessed so easily.

I mean, wouldn't you kill for a video of Mars of the type we see here for the moon? I would. But nothing in orbit of Mars right now has any capacity to do it, with weight being at such a premium. Someday, maybe. Until then, we get to dream, and look at kickass Japanese videos of the moon. :)

Mark
 
They should fly over the moon landing spot and take video, to prove all the conspiracy theorists wrong, but also just cause it would be cool.
 
Okay, for the life of me I can't remember which show it was on the Science Channel right now, but there's actually a lab where they've taken the images from the Mars Orbital Camera and built 3-D virtual reality displays of the surface of Mars from them that they can actually walk through.
 
The NASA has so much film of and on the moon, it cannot be fake. There is a link in this thread that shows everything. ;)

Btw, on the japanese site there is also a video showing both rising and setting Earth. Quite cool.
 
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