Diary note: Pluto's close-up is a year from … now! NASA's New Horizons mission will arrive at Pluto 364 days from … now! Launched in January 2006, the craft passed Jupiter back in 2007. It hasn't had much to do since, as while it has passed the orbits of Saturn, Uranus and Neptune the planets weren't there at the time. NASA's not worried about that, because New Horizons' …
bigphil9009,
I'd imagine the bandwidth is going to suck for nice pictures. So it'll store those and start transmitting the most interesting data first. After all, we now have better instruments than the old probes did. And we can often do more things at once, and stick the results into storage for later transmission.
Just a guess, but are any of the gas giants moving between us and the probe in that period as well? They're noisy and might interfere with the signal.
The other option is that NASA cut costs too much and used O2 for their data...
It's primarily bandwidth related, but that drives Deep Space Network access. The radio transmissions get pretty feeble transmitting from Pluto's neighborhood to Earth when they started out at ~15 Watts, which means it takes a long time to deliver a bit of information.
From Pluto, transmission rates are expected to be 1 kilobit per second (versus the 38kb/s New Horizons achieved at Jupiter). At 1 kb/s, it takes a while to deliver ~8 gigabytes of data - about 3 months if the receiver can pay attention to New Horizons alone.
But because of the low transmission rates, DSN time then plays into it. New Horizons needs the 70-meter dishes and there are only 3 of those (I think), which have to switch between a number of deep space missions. And then you're up to 9 months, especially if some sections need to be re-transmitted.
For those more up on the DSN than me, are NASA considering putting a satellite up to improve the network? I know that there's some capability to use some probes to relay from others - but would it be worth putting something at one of the Lagrange points?
I wonder if this could be a job for a small collection of micro sats to work as an array antenna? Then the array might be able to point in different directions at once.
Bandwidth. At that distance the download rate will be 1Kbits/s using the 70m dishes of the Deep Space Network. (they might be able to do 2Kbits/s with some upgrades to the DNS)
Also, the DNS is needed for a lot of other missions, so there will be a schedule balancing act as well.
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