10 ms·

Nasa's New Horizons: Final flyby commands given to distant probe

152 points by gpvos 8y ago

dogma1138 8y ago
The final command for this part of the mission as no further communications would be possible until the flyby has been complete and the probe can reorient itself to call back home, it would take 18 months to get the data back from New Horizons as its current data rate is 1kbp/s or 2 with induced spin. This isn’t the end of the mission for NH.
- marktangotango 8y ago
  Thanks for clarifying that. The velocity of this probe is really astounding!
- madengr 8y ago
  I’m currently reading this book about the history of the DSN. https://www.amazon.com/Uplink-Downlink-History-Space-Network-1957-1997/dp/1494740613 https://www.amazon.com/Uplink-Downlink-History-Space-Network... Fascinating stuff. I wonder how they will manage the priority of getting that data back over the next two years? Timeshareing on the DSN has been a problem since the early 60’s.
  - dogma1138 8y ago
    I’m not sure they can even get all of the data back. The probe has limited data storage capacity and even more limited bandwidth to send it back to earth. I’m guessing they have a protocol to prioritize data from different instruments as well as prioritize data purging if there is an opportunity to look at something more interesting before everything could be sent back home. It can be a heartbreaking process for some of the teams for sure. My best bet is that they get some initial indication of what data was collected then prioritize based on what they think is the most interesting or valuable from what was collected. They were still retrieving data form the original Pluto flyby as this one was planned I’m not sure if they even got all the data from pluto yet.
    - jessriedel 8y ago
      > purging if there is an opportunity to look at something more interesting before everything could be sent back home. This is not a risk as, with high probability, there is nothing else on their trajectory they will be able to look at for the 18-month downlink time. > I’m not sure if they even got all the data from pluto yet. They did. It's true that they have limited data storage space, but they have had plenty of time to download the entire data set from Pluto. https://futurism.com/it-took-15-months-but-all-of-new-horizons-data-has-finally-been-downloaded/ https://futurism.com/it-took-15-months-but-all-of-new-horizo... I believe the major constraint is how much data they can take during the short flyby time, not storage space or downlink time.
      - dogma1138 8y ago
        Well it sorta both yes the flybys at this point are so short that the amount of data they collect is limited but they still collect GB’s of data and the up line data rate will likely drop even further as the probe goes further. It’s still astonishing to me that they can get 1kbp/s with s 1.5m dish antenna pointed at a target 0.29281 arc minutes in size. This is the equivalent of pissing into your toilet form orbit. But heck now the FCC can claim that broadband coverage has been expanded up to the Kuiper Belt.
    - tabtab 8y ago
      Re: I'm guessing they have a protocol to prioritize data from different instruments as well as prioritize data purging if there is an opportunity to look at something more interesting before everything could be sent back home. I suspect if a new nearby target were discovered, they may have to send back just thumbnails and summarized/compressed data, review the summaries back on Earth, and only request the more promising full images and data snippets. I just hope they already have such compression/summarizing software onboard because sending significant new software that far can be a bear. I wonder if they planned for such a "rush job" scenario?
      - dogma1138 8y ago
        It’s main CPU is a 12mhz MIPS processor I don’t think they do any complex software analysis on board.
- sizzzzlerz 8y ago
  Is that the effective payload data rate after error correction has been applied or the actual transmitted bit rate meaning that the payload rate is much less? I've read that NH uses a 1/6 Turbo code for forward error correction. If true, that would imply that the transmitted data rate is actually 5 to 10 kbps or the payload rate (after e.c.) is 200-400 bps.
  - dogma1138 8y ago
    That’s the data rate afaik http://pluto.jhuapl.edu/Mission/Spacecraft/Data-Collection.php http://pluto.jhuapl.edu/Mission/Spacecraft/Data-Collection.p... https://en.m.wikipedia.org/wiki/New_Horizons#Telecommunications_and_data_handling https://en.m.wikipedia.org/wiki/New_Horizons#Telecommunicati... Pluto encounter data rate was 2000 bp/s but that is with the spin, I’m guessing it’s lower now since it’s well past Pluto. I can’t find the link to the interview which had a bit more information about it now, but I don’t think they refer to the payload data rate.
    - tabtab 8y ago
      New Horizons can't use many of its scientific instruments and cameras in spin mode. Spin mode gyroscopically stabilizes it so that its main antenna can be pointed more precisely, allowing a higher data rate. Thus, I suspect they won't want to enter spin mode until it's no longer doing any photographic or scientific observations of Thule. Therefore, data packets will be slow in the days before and after encounter because they want to still aim instruments; but this makes antenna pointing less precise. New Horizons can't chew gum and talk at the same time :-)
      - dogma1138 8y ago
        Again they won’t plan missions in this manner, in the rare event that they’ll need to override data they’ll have a clear protocol sending a summary in this case would be a waste of bandwidth.
        tabtab 8y ago
- jcims 8y ago
  >This isn’t the end of the mission for NH. At ~1:30 in the video interview with Alan Stern he says they have ~20 years of power in the RTG and 'plenty of fuel' to get around. Sounds like there could be a lot of science yet to come!!
  - tabtab 8y ago
    The Hubble scope had to spend many hours to find this target, basically taking "before" and "after" images to find changes: dots moving against the background stars seen via subtracting the pixels values of before and after. Once they find rough candidates, they take more pics to narrow down their orbits. Any new targets will be further away and thus probably dimmer to Hubble than Thule. Also, New Horizons only has so much fuel to change direction. Its room to operate is a very narrow cone, kind of like a long lopsided straw. It will be challenging finding new objects to visit. I wish they didn't have to depend on Hubble so much.
    - accnumnplus1 8y ago
      Time to send a telescope into distant orbit?
      - tabtab 8y ago
        You mean send a Telescope to the Kuiper Belt? I believe resources would be better spent sending a probe to one or few of the bigger Kuiper Belt objects, such as Eris and Sedna. New Horizon's "target problem" is rather specific to that probe. Pluto was its primary mission. Other bodies were considered a bonus, and the probe doesn't have enough fuel to target the bigger (known) objects. Perhaps that was a mistake; but many of these were discovered after the probe was budgeted.
      - lmilcin 8y ago
        There would be no reason to do that. Putting telescope into distant orbit will not make it easier to observe anything except for the thing you are orbiting. The problem with kuiper belt objects is not that they are far away but that there is not much light reflected from them. The belt is huge, and if you put say Hubble in there you have no guarantee you would see anything. Putting space observatory is costly project, money are better spent by putting it in Earth orbit as it is much cheaper to put it there and possible to service while in orbit. If history teaches us anything it is that being able to service the telescope in orbit is very important for getting as much bang for the buck as possible.
SOMA_BOFH 8y ago
it's leaving the solar system but no golden record. instead, it has a quarter, a flag, human ashes and a cd-rom disc without a drive or a codec. srsly?
- iamamrit 8y ago
  Well, if they are going to ship a codec, they will have to make a choice for the CPU architecture or even have to ship a CPU. Then they might have to ship some batteries as well
  - minipci1321 8y ago
    And of course, a full source code and the cross-compiler. On a CD-ROM.
    - heyjudy 8y ago
      Lol. But seriously, the irony is CD-ROM's degrade to completely unusable within a century due to disc rot. A CD-ROM made with gold and completely encapsulated in an extremely stable enamel might work. Then, leaving universal instructions as to how to use said CD-ROM is important, rather than arrogantly presumptive anthropocentrism.
      - madengr 8y ago
        A CD-ROM rots fast due to the deyes, but what about a normal pressed CD of aluminum? Those should be pretty stable. I have only seen those destroyed with sunlight.
      - pfarnsworth 8y ago
        Do you think NASA burned a 24x CD-ROM from their PC and added it to New Horizons?
- etatoby 8y ago
  CD-ROM? As in ISO 9660 data disc? That's going to be a hell of a challenge to reverse engineer for alien civilizations.
garmaine 8y ago
‘... before Ultima Thule encounter” should be added to title.
eponeponepon 8y ago
I'm really quite excited about this. I don't know if I'd just completely missed it, or if they it hadn't had much publicity in the mainstream press, but it was a pleasant surprise to read about yesterday!
- garmaine 8y ago
  Well the government shutdown means that there's been no NASA PR for this.
  - tabtab 8y ago
    Fortunately, the Johns Hopkins University is posting some news and materials because they operate part of the mission. Here is where they will post raw images: http://pluto.jhuapl.edu/soc/UltimaThule-Encounter/ http://pluto.jhuapl.edu/soc/UltimaThule-Encounter/ More links: http://pluto.jhuapl.edu/News-Center/ http://pluto.jhuapl.edu/News-Center/
zipotm 8y ago
Please read here: http://expreso.co.cr/centaurs/essays/uranians.html http://expreso.co.cr/centaurs/essays/uranians.html - So called "Cupido" at 40.998 AU may be the same as "Ultima Thule" object/planet. Research is done by Alfred Witte, based on Sun vibrational field which is creating standing scalar waves and forming the physical planets.
- eesmith 8y ago
  "may be"? How about, no, it isn't. The astrology link you pointed to says: > 1- they are completely idealized points moving in perfect circles around the sun without any physical acceleration except the Sun's, i.e. > 2- they are subject only to the influence of the Sun and are not affected by the gravitational interactions of other large bodies. This is not true of Ultima Thule, with a perihelion of 42.721 AU and aphelion of 46.442 AU. Its semi-major axis is nearly 10% larger than the mean solar distance of 40.998 you quoted. The text goes on to insist that "things in Astrology work very well even though they do not or cannot physically exist", so why is there a need to have it exist? Furthermore, user "Juan" points out the problems in the analysis, such as "it is obvious that the more asteroids you put into the equation, the more likely you will find one that resembles in its motion the orbit at least of Cupido". And the suggestion that 2000 KL4 matches Cupido. How do we tell which is "really" Cupido?
kzrdude 8y ago
Exciting! Sounds like they will get reasonable pictures (but the object is quite small). 190 Watts is now equivalent to 20 lightbulbs, not 3 like the article suggests :) since we've moved away from the incandescent ones.
- behringer 8y ago
  We're going to need to compare electricity usage against some new appliance. How about GPUs :P The probe takes as much power as one high end GPU.
  - pavel_lishin 8y ago
    "This probe can mine up to one bitcoin a week!"
- garmaine 8y ago
  At the distance they will be at closest approach, Ultima Thule will extend through as much of the sky as the full moon does to us on Earth. This is actually not all that large, but anyone who has looked at the moon through a telescope can attest to the phenomenal detail that is possible, and New Horizons is equipped with some high calibre telescopic instruments.
sandworm101 8y ago
Anyone else hoping this rock is a bracewell probe? Im so sick of mars rovers. It is refreshing for a probe to be discovering something totally new. This rock (or maybe group of rocks) was only a handful of pixels last week. Next week it could be almost anything.
- trentnix 8y ago
  I’m holding out hope it’s the skull from a dead Celestial.
  - sandworm101 8y ago
    Why not? Every space scientist would give thier entire career, every dollar ever spent by nasa, for even a hint of such a discovery. When gravity wave detectors were first turned on every scifi fan was hoping we would see warp drives buzzing around. That sense of wonder, of unlimited possibility, is the real reason we explore such distant places.
    - bloopernova 8y ago
      My hope is that if there are whole new levels of science that haven't yet even glimpsed, then the aliens using that science are so far advanced that we have no hope of viewing the footprints they leave across the galaxy. Or perhaps that they have a very strict prime-directive-style zero-interference policy that they've built something that protects us from seeing anything out of the ordinary until we reach a certain level. It may be that such esoteric or advanced sciences can really mess up your local star system if handled poorly, so they want to keep immature hands away from the stove, so to speak. Neither of those possibilities really mean that we should be doing anything different regarding our peering into the cosmos. There's certainly wonders already in our view that are beyond anything we can really comprehend.
    - garmaine 8y ago
      > Every space scientist would give thier entire career, every dollar ever spent by nasa, for even a hint of such a discovery. Not everyone (case in point: me). We're not all obsessed with the search for ET.
shagie 8y ago
Its kind of neat watching The Deep Space Network - https://eyes.nasa.gov/dsn/dsn.html https://eyes.nasa.gov/dsn/dsn.html Nearly every dish is receiving or sending to NHPC.

152 points by gpvos 8y ago

The final command for this part of the mission as no further communications would be possible until the flyby has been complete and the probe can reorient itself to call back home, it would take 18 months to get the data back from New Horizons as its current data rate is 1kbp/s or 2 with induced spin. This isn’t the end of the mission for NH.

marktangotango 8y ago
Thanks for clarifying that. The velocity of this probe is really astounding!
madengr 8y ago
I’m currently reading this book about the history of the DSN. https://www.amazon.com/Uplink-Downlink-History-Space-Network-1957-1997/dp/1494740613 https://www.amazon.com/Uplink-Downlink-History-Space-Network... Fascinating stuff. I wonder how they will manage the priority of getting that data back over the next two years? Timeshareing on the DSN has been a problem since the early 60’s.
- dogma1138 8y ago
  I’m not sure they can even get all of the data back. The probe has limited data storage capacity and even more limited bandwidth to send it back to earth. I’m guessing they have a protocol to prioritize data from different instruments as well as prioritize data purging if there is an opportunity to look at something more interesting before everything could be sent back home. It can be a heartbreaking process for some of the teams for sure. My best bet is that they get some initial indication of what data was collected then prioritize based on what they think is the most interesting or valuable from what was collected. They were still retrieving data form the original Pluto flyby as this one was planned I’m not sure if they even got all the data from pluto yet.
  - jessriedel 8y ago
    > purging if there is an opportunity to look at something more interesting before everything could be sent back home. This is not a risk as, with high probability, there is nothing else on their trajectory they will be able to look at for the 18-month downlink time. > I’m not sure if they even got all the data from pluto yet. They did. It's true that they have limited data storage space, but they have had plenty of time to download the entire data set from Pluto. https://futurism.com/it-took-15-months-but-all-of-new-horizons-data-has-finally-been-downloaded/ https://futurism.com/it-took-15-months-but-all-of-new-horizo... I believe the major constraint is how much data they can take during the short flyby time, not storage space or downlink time.
    - dogma1138 8y ago
      Well it sorta both yes the flybys at this point are so short that the amount of data they collect is limited but they still collect GB’s of data and the up line data rate will likely drop even further as the probe goes further. It’s still astonishing to me that they can get 1kbp/s with s 1.5m dish antenna pointed at a target 0.29281 arc minutes in size. This is the equivalent of pissing into your toilet form orbit. But heck now the FCC can claim that broadband coverage has been expanded up to the Kuiper Belt.
  - tabtab 8y ago
    Re: I'm guessing they have a protocol to prioritize data from different instruments as well as prioritize data purging if there is an opportunity to look at something more interesting before everything could be sent back home. I suspect if a new nearby target were discovered, they may have to send back just thumbnails and summarized/compressed data, review the summaries back on Earth, and only request the more promising full images and data snippets. I just hope they already have such compression/summarizing software onboard because sending significant new software that far can be a bear. I wonder if they planned for such a "rush job" scenario?
    - dogma1138 8y ago
      It’s main CPU is a 12mhz MIPS processor I don’t think they do any complex software analysis on board.
sizzzzlerz 8y ago
Is that the effective payload data rate after error correction has been applied or the actual transmitted bit rate meaning that the payload rate is much less? I've read that NH uses a 1/6 Turbo code for forward error correction. If true, that would imply that the transmitted data rate is actually 5 to 10 kbps or the payload rate (after e.c.) is 200-400 bps.
- dogma1138 8y ago
  That’s the data rate afaik http://pluto.jhuapl.edu/Mission/Spacecraft/Data-Collection.php http://pluto.jhuapl.edu/Mission/Spacecraft/Data-Collection.p... https://en.m.wikipedia.org/wiki/New_Horizons#Telecommunications_and_data_handling https://en.m.wikipedia.org/wiki/New_Horizons#Telecommunicati... Pluto encounter data rate was 2000 bp/s but that is with the spin, I’m guessing it’s lower now since it’s well past Pluto. I can’t find the link to the interview which had a bit more information about it now, but I don’t think they refer to the payload data rate.
  - tabtab 8y ago
    New Horizons can't use many of its scientific instruments and cameras in spin mode. Spin mode gyroscopically stabilizes it so that its main antenna can be pointed more precisely, allowing a higher data rate. Thus, I suspect they won't want to enter spin mode until it's no longer doing any photographic or scientific observations of Thule. Therefore, data packets will be slow in the days before and after encounter because they want to still aim instruments; but this makes antenna pointing less precise. New Horizons can't chew gum and talk at the same time :-)
    - dogma1138 8y ago
      Again they won’t plan missions in this manner, in the rare event that they’ll need to override data they’ll have a clear protocol sending a summary in this case would be a waste of bandwidth.
      - tabtab 8y ago
jcims 8y ago
>This isn’t the end of the mission for NH. At ~1:30 in the video interview with Alan Stern he says they have ~20 years of power in the RTG and 'plenty of fuel' to get around. Sounds like there could be a lot of science yet to come!!
- tabtab 8y ago
  The Hubble scope had to spend many hours to find this target, basically taking "before" and "after" images to find changes: dots moving against the background stars seen via subtracting the pixels values of before and after. Once they find rough candidates, they take more pics to narrow down their orbits. Any new targets will be further away and thus probably dimmer to Hubble than Thule. Also, New Horizons only has so much fuel to change direction. Its room to operate is a very narrow cone, kind of like a long lopsided straw. It will be challenging finding new objects to visit. I wish they didn't have to depend on Hubble so much.
  - accnumnplus1 8y ago
    Time to send a telescope into distant orbit?
    - tabtab 8y ago
      You mean send a Telescope to the Kuiper Belt? I believe resources would be better spent sending a probe to one or few of the bigger Kuiper Belt objects, such as Eris and Sedna. New Horizon's "target problem" is rather specific to that probe. Pluto was its primary mission. Other bodies were considered a bonus, and the probe doesn't have enough fuel to target the bigger (known) objects. Perhaps that was a mistake; but many of these were discovered after the probe was budgeted.
    - lmilcin 8y ago
      There would be no reason to do that. Putting telescope into distant orbit will not make it easier to observe anything except for the thing you are orbiting. The problem with kuiper belt objects is not that they are far away but that there is not much light reflected from them. The belt is huge, and if you put say Hubble in there you have no guarantee you would see anything. Putting space observatory is costly project, money are better spent by putting it in Earth orbit as it is much cheaper to put it there and possible to service while in orbit. If history teaches us anything it is that being able to service the telescope in orbit is very important for getting as much bang for the buck as possible.

SOMA_BOFH 8y ago

it's leaving the solar system but no golden record. instead, it has a quarter, a flag, human ashes and a cd-rom disc without a drive or a codec. srsly?

iamamrit 8y ago
Well, if they are going to ship a codec, they will have to make a choice for the CPU architecture or even have to ship a CPU. Then they might have to ship some batteries as well
- minipci1321 8y ago
  And of course, a full source code and the cross-compiler. On a CD-ROM.
  - heyjudy 8y ago
    Lol. But seriously, the irony is CD-ROM's degrade to completely unusable within a century due to disc rot. A CD-ROM made with gold and completely encapsulated in an extremely stable enamel might work. Then, leaving universal instructions as to how to use said CD-ROM is important, rather than arrogantly presumptive anthropocentrism.
    - madengr 8y ago
      A CD-ROM rots fast due to the deyes, but what about a normal pressed CD of aluminum? Those should be pretty stable. I have only seen those destroyed with sunlight.
    - pfarnsworth 8y ago
      Do you think NASA burned a 24x CD-ROM from their PC and added it to New Horizons?
etatoby 8y ago
CD-ROM? As in ISO 9660 data disc? That's going to be a hell of a challenge to reverse engineer for alien civilizations.

garmaine 8y ago

‘... before Ultima Thule encounter” should be added to title.

eponeponepon 8y ago

I'm really quite excited about this. I don't know if I'd just completely missed it, or if they it hadn't had much publicity in the mainstream press, but it was a pleasant surprise to read about yesterday!

garmaine 8y ago
Well the government shutdown means that there's been no NASA PR for this.
- tabtab 8y ago
  Fortunately, the Johns Hopkins University is posting some news and materials because they operate part of the mission. Here is where they will post raw images: http://pluto.jhuapl.edu/soc/UltimaThule-Encounter/ http://pluto.jhuapl.edu/soc/UltimaThule-Encounter/ More links: http://pluto.jhuapl.edu/News-Center/ http://pluto.jhuapl.edu/News-Center/

zipotm 8y ago

Please read here: http://expreso.co.cr/centaurs/essays/uranians.html http://expreso.co.cr/centaurs/essays/uranians.html - So called "Cupido" at 40.998 AU may be the same as "Ultima Thule" object/planet. Research is done by Alfred Witte, based on Sun vibrational field which is creating standing scalar waves and forming the physical planets.

eesmith 8y ago
"may be"? How about, no, it isn't. The astrology link you pointed to says: > 1- they are completely idealized points moving in perfect circles around the sun without any physical acceleration except the Sun's, i.e. > 2- they are subject only to the influence of the Sun and are not affected by the gravitational interactions of other large bodies. This is not true of Ultima Thule, with a perihelion of 42.721 AU and aphelion of 46.442 AU. Its semi-major axis is nearly 10% larger than the mean solar distance of 40.998 you quoted. The text goes on to insist that "things in Astrology work very well even though they do not or cannot physically exist", so why is there a need to have it exist? Furthermore, user "Juan" points out the problems in the analysis, such as "it is obvious that the more asteroids you put into the equation, the more likely you will find one that resembles in its motion the orbit at least of Cupido". And the suggestion that 2000 KL4 matches Cupido. How do we tell which is "really" Cupido?

kzrdude 8y ago

Exciting! Sounds like they will get reasonable pictures (but the object is quite small). 190 Watts is now equivalent to 20 lightbulbs, not 3 like the article suggests :) since we've moved away from the incandescent ones.

behringer 8y ago
We're going to need to compare electricity usage against some new appliance. How about GPUs :P The probe takes as much power as one high end GPU.
- pavel_lishin 8y ago
  "This probe can mine up to one bitcoin a week!"
garmaine 8y ago
At the distance they will be at closest approach, Ultima Thule will extend through as much of the sky as the full moon does to us on Earth. This is actually not all that large, but anyone who has looked at the moon through a telescope can attest to the phenomenal detail that is possible, and New Horizons is equipped with some high calibre telescopic instruments.

sandworm101 8y ago

Anyone else hoping this rock is a bracewell probe? Im so sick of mars rovers. It is refreshing for a probe to be discovering something totally new. This rock (or maybe group of rocks) was only a handful of pixels last week. Next week it could be almost anything.

trentnix 8y ago
I’m holding out hope it’s the skull from a dead Celestial.
- sandworm101 8y ago
  Why not? Every space scientist would give thier entire career, every dollar ever spent by nasa, for even a hint of such a discovery. When gravity wave detectors were first turned on every scifi fan was hoping we would see warp drives buzzing around. That sense of wonder, of unlimited possibility, is the real reason we explore such distant places.
  - bloopernova 8y ago
    My hope is that if there are whole new levels of science that haven't yet even glimpsed, then the aliens using that science are so far advanced that we have no hope of viewing the footprints they leave across the galaxy. Or perhaps that they have a very strict prime-directive-style zero-interference policy that they've built something that protects us from seeing anything out of the ordinary until we reach a certain level. It may be that such esoteric or advanced sciences can really mess up your local star system if handled poorly, so they want to keep immature hands away from the stove, so to speak. Neither of those possibilities really mean that we should be doing anything different regarding our peering into the cosmos. There's certainly wonders already in our view that are beyond anything we can really comprehend.
  - garmaine 8y ago
    > Every space scientist would give thier entire career, every dollar ever spent by nasa, for even a hint of such a discovery. Not everyone (case in point: me). We're not all obsessed with the search for ET.

shagie 8y ago

Its kind of neat watching The Deep Space Network - https://eyes.nasa.gov/dsn/dsn.html https://eyes.nasa.gov/dsn/dsn.html Nearly every dish is receiving or sending to NHPC.