Comments on: New Horizons returns the last data from Pluto fly-by

By: Gealon

Gealon — Fri, 28 Oct 2016 15:05:35 +0000

Good to see they are practicing good data preservation techniques. Would hate for those long distance emails to get lost.

And on the less silly side of things, while RTG’s have proven themselves to be useful in long duration missions where solar power is untenable, they are massively underpowered compared to the wattages one can get from a solar array, fuel cell, or nuclear reactor. Unfortunately, as was stated above, anything nuclear is looked down upon in the political world, especially when the word “Reactor” is tacked on, even worse if you use the word “Atomic.” They automatically think you’re some Dr. Strangelove/General Ripper reject if you use that word.

But nuclear power truly is the only viable way to go. NTR propulsion would greatly reduce travel times and space based reactor technology would make possible other forms of propulsion as well that are as yet, unrealized, like MPD thrusters. Reactors would also produce the power needed to utilize higher bit rate radio and even laser communications. But politics as always seems to be the case, is in the way. I’m glad to see the Russians SLOWLY preparing to test a model of a nuclear engine, but we’ve had a functional engine for decades and have never used it on a space craft. That has to change if we are ever going to leave this planet.

By: Wayne

Wayne — Fri, 28 Oct 2016 14:29:30 +0000

From the video–
>Downlink can handle about 7 MB’s per hour for 2, 8-hour passes per day.

The efficiency of these RTG’s is something like 10%, but newer designs using different isotopes, point toward ramping that up to 30% or more. (but as Localfluff opined– “it’s political.”)

By: LocalFluff

LocalFluff — Fri, 28 Oct 2016 06:16:04 +0000

@Blair Ivey, It isn’t light speed that is limiting the download speed. Light takes only about 4½ hours to reach Earth from New Horizons. It is the low signal strength that requires low data frequency or repeated transmissions to be received, even by 100 meter sized radio telescopes in the DSN. And the low signal strength is because of the probe’s low power supply. Beyond Jupiter (at least Saturn) solar power is not an option. And RTGs, the plutonium “battery” running New Horizons is a sloth by design, I hear it is very expensive to scale up. The only solution for an ambitious exploration of the outer Solar system would be using proper nuclear power plants, but those are politically banned.

By: Blair Ivey

Blair Ivey — Fri, 28 Oct 2016 02:57:27 +0000

Happy to hear that the data is (presumably) complete, but the transmission times illustrate how slow light really is.

By: wayne

wayne — Thu, 27 Oct 2016 22:31:06 +0000

Ref: “…they will wipe the spacecraft’s onboard hard drives..”
“Do you mean, like, with a cloth?”

On a more serious note; the short video at the website is very informative, as to how they accomplished the download.
[This is Amazing Stuff!]

Total techie question:
What kind of Hard-Drive(s) are on-board? Solid-State or what?