Does anyone know what Cassini's current data transmission rate is? I figured it would be higher now that Saturn has reached opposition with Earth. I know that made a difference with Galileo.

165 kbps is the peak rate at this time of the year for 70m or arrayed stations

According to the Cassini Significant Events for 04/20/06 - 04/25/06:

Friday, April 21 (DOY 111)

The Mission Support & Services Office has provided some approximate numbers
of the amount of science data that has been collected since January 1, 2004.

The data is complete through April 19, 2006.

Instrument Data:

CAPS 26,283,460kbytes
CDA 8,770,209kbytes
CIRS 7,135,426kbytes
INMS 801,804kbytes
ISS 24,057,854kbytes
MAG 10,465,190kbytes
MIMI 8,360,273kbytes
RADAR 1,650,522kbytes
RPWS 39,422,594kbytes
UVIS 6,021,474kbytes
VIMS 5,605,781kbytes

Total science data is 138,574,587 kbytes or roughly 132 gbytes.

RADAR has the second lowest amount of data returned??? I have to say that I am completely shocked by that. I knew it was a very large amount, but I am surprised it is only ~1.6 GB.

Well, it and INMS are by far the lowest in data return -- and the reason for that is pretty obviously that, unlike the other instruments, they are almost always used only during Titan flybys. (The real shocker is the huge amount of data returned by the plasma and plasma-wave experiments.)

So how does that compare with other missions? Considering Galileo's antenna problems, that's probably more than Galileo sent its entire lifetime.

It's been my thought too. ISS much less than ten percent of the total data volume! WAC and NAC (together with PWS) were sending by far the most bits from Voyager. The fields and particel instruments (and even the spectrometers) were in the few hundred bps area.



Definitely yes. Galileo was transmitting at 100bps or a little more (less than 1000bps).