New Horizons returns the last data from Pluto fly-by

Pioneer cover

From the press release: From the moment he is handed a possibility of making the first alien contact, Saunders Maxwell decides he will do it, even if doing so takes him through hell and back.

Unfortunately, that is exactly where that journey takes him.

The vision that Zimmerman paints of vibrant human colonies on the Moon, Mars, the asteroids, and beyond, indomitably fighting the harsh lifeless environment of space to build new societies, captures perfectly the emerging space race we see today.

He also captures in Pioneer the heart of the human spirit, willing to push forward no matter the odds, no matter the cost. It is that spirit that will make the exploration of the heavens possible, forever, into the never-ending future.

Available everywhere for $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from the ebook publisher, ebookit.

The New Horizons science team announced today that they have finally received the last bit of data obtained by the spacecraft during its July 14, 2015 fly-by of Pluto.

Having traveled from the New Horizons spacecraft over 3.1 billion miles (five hours, eight minutes at light speed), the final item – a segment of a Pluto-Charon observation sequence taken by the Ralph/LEISA imager – arrived at mission operations at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, at 5:48 a.m. EDT on Oct. 25. The downlink came via NASA’s Deep Space Network station in Canberra, Australia. It was the last of the 50-plus total gigabits of Pluto system data transmitted to Earth by New Horizons over the past 15 months.

Once they have checked this data, they will wipe the spacecraft’s onboard hard drives to prepare for the January 1, 2019 fly-by of Kuiper Belt object 2014 MU69.


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  • wayne

    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?

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

  • LocalFluff

    @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.

  • Wayne

    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.”)

  • Gealon

    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.

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