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Space

New Horizons Spacecraft Wakes Up To Prepare For Historic Flyby of Distant Object (space.com) 36

jwhyche writes: The New Horizons space probe has been in hibernation mode since Dec. 21. On June 5th, the spacecraft exited hibernation mode and began preparing for its next encounter. The spacecraft is currently 3.7 billion miles from Earth and will be spending the next few months preparing for its flyby of a small Kuiper Belt object nicknamed Ultima Thule (officially 2014 MU69). The craft is expected to pass by Ultima Thule during the New Year's holiday.
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New Horizons Spacecraft Wakes Up To Prepare For Historic Flyby of Distant Object

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  • Actual press release (Score:5, Informative)

    by tonique ( 1176513 ) on Saturday June 09, 2018 @02:25AM (#56754324)
    A link to to the actual New Horizons site [jhuapl.edu] should be informative as well.
  • by rossdee ( 243626 )

    Its spent 6 months in hibernation, and is woken up now to prepare for the fly past that is still more than 6 months away?

    I would have told mission control to FO and wake me when we are a couple of weeks out..

    • by Anonymous Coward

      Part of the reason they have to wake it up this early is that the data rate from that far out is approaching telegram speeds.

      HELLO NASA STOP
      GETTING TOO CLOSE TO MU69 STOP
      PLEASE ADVISE STOP

      • PLEASE STOP STOP

      • Since both forms of communication work at the speed of light, that's exactly correct: it'll take about 5.5 hours for the telegram to reach New Horizons.

        • Considering that the earliest trans-Atlantic cable transmissions could take around 24 hours just to go from one continent to another, and New Horizons is billions of miles away, I would say that we have made much happyjoy! smiles progress! :)
          • I'm going to be generous and—rather than ask for a citation I know doesn't exist—assume that you were trying to be funny.

            (Don't quit your day job.)

            • Re:So (Score:4, Interesting)

              by Waffle Iron ( 339739 ) on Saturday June 09, 2018 @12:58PM (#56755994)

              I'm going to be generous and—rather than ask for a citation I know doesn't exist—assume that you were trying to be funny.

              He may be alluding to the first transatlantic cable (1850s), where they didn't fully understand electromagnetic signal propagation, and they damaged the cable by overdriving it with high voltage in an attempt to improve reception. Before it completely failed, the bandwidth became so low that it took a whole day to send a single short message.

              Any individual bit sent was much shorter, of course, but the signal-to-noise ratio was so bad that it took a long time to decipher each bit. So in practical terms, it wasn't really anywhere close to the speed of light.

            • Well, so I was off a bit...[1] [lac-bac.gc.ca]

              "The Queen's message to Washington commenced transmission at 10:50 am on August 16, and was completed at 4:30am the next day, taking 17 hours and 40 minutes."

              But if you go by average character transmission speed, my number does misrepresent - oops. : )

          • by Tablizer ( 95088 )

            Comcast

      • One of the system requirements of the New Horizons telecommunication system is a minimum post-encounter end-of-playback data rate of 600 bps. From "The RF Telecommunications System for the New Horizons Mission to Pluto [psu.edu]":

        A 16 bit control register is used to provide 65532 possible downlink data rates, from a minimum of 6.3578 bps to a maximum of 104.167 kbps. The relation between control word setting n and the data rate is BitRate = (5 MHz) / (12 * (n + 1)) where n is between 3 and 65536, inclusive. The fine

      • Part of the reason they have to wake it up this early is that the data rate from that far out is approaching telegram speeds.

        HELLO NASA STOP
        GETTING TOO CLOSE TO MU69 STOP
        PLEASE ADVISE STOP

        This is why sexting in Victorian London was so hilarious.

    • by quenda ( 644621 )

      Its spent 6 months in hibernation, and is woken up now to prepare for the fly past that is still more than 6 months away?

      Maybe it is running Windows 10, and has a few hundred megabytes of forced updates before it will boot? The bandwidth is poor out there. But the lag!

    • The itinerary must be fixed early. A few degrees error over 6 months would make a big distance difference to the target.
  • I'm glad it doesn't take several months to wake my desktop computer. That would just be an endless nightmare!

  • by MichaelSmith ( 789609 ) on Saturday June 09, 2018 @02:37AM (#56754350) Homepage Journal

    And its twelve years old.

    Yep, becoming a teenager.

  • Why now (Score:5, Informative)

    by hackertourist ( 2202674 ) on Saturday June 09, 2018 @05:38AM (#56754642)

    To answer the inevitable question, "why wake it up now when the flyby is 6 months from now",

    - the team needs time to check the spacecraft
    - it needs to upload new software for the encounter, at speeds in the region of 1 kbit/s
    - the spacecraft needs to do some observations to help in navigation. The targeted KBO is called 2014 MU69 because it was discovered in 2014, meaning we have very little data to derive its orbit from. Pre-flyby observations help finetune the flyby distance (has to be as close as possible to get good photos).

    Over the next three days, the mission team will collect navigation tracking data (using signals from the Deep Space Network) and send the first of many commands to New Horizons' onboard computers to begin preparations for the Ultima flyby; lasting about two months, those flyby preparations include memory updates, Kuiper Belt science data retrieval, and a series of subsystem and science-instrument checkouts. In August, the team will command New Horizons to begin making distant observations of Ultima, images that will help the team refine the spacecraft's course to fly by the object.

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