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NASA Wants New Space Net To Sustain Big Data Dumps; Moon and Mars Trips

Posted by Unknown on from the world-of-mooncraft dept.

coondoggie writes "What kind of network can support future commercial and government space trips around Earth and support bigger distances to the moon and Mars? NASA is in the process of exploring exactly what technology will be needed beyond 2022 in particular to support future space communication and navigation. The agency recently issued a Request for Information (RFI) to begin planning for such a new architecture."

9 of 63 comments (clear)

  1. space trips around Earth?? by Anonymous Coward · · Score: 2, Insightful

    That's pretty much all we can manage. All we need is '60s technology for that, jeez.

  2. Big plans by Dyolf+Knip · · Score: 3, Insightful

    NASA sure does dream big, considering they can barely even get to LEO these days. Their launch capacity has been diminishing steadily for the past 40 years. Thank goodness it's not entirely up to them anymore.

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    Dyolf Knip
    1. Re:Big plans by ganjadude · · Score: 4, Insightful

      to be fair, NASA gets all the cuts by congress first. On top of that, everytime they have a multi year-decade plan, the *insert sitting president here* decides that the *insert previous president here*'s plan is no good, and makes NASA start over or shift to a new project. It really is no wonder why NASA is not what it could be, just follow the money

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    2. Re:Big plans by KeensMustard · · Score: 2
      Nasa can, and does, get regularly beyond LEO. Off the top of my head:

      1. Spirit and Opportunity rovers - huge success

      2. Cassini-Huygens: Despite some issues, still managed to collect an enormous amount of data on probably the most (or perhaps second most) interesting place in the solar system - including a landing on Titan. Arguably the high point of space exploration so far.

      3. Curiousity Rover - again, hugely successful

      4. MESSENGER probe - has has it's mission extended, having achieved every mission objective

      5. And of course New Horizons my current favourite

      Their launch capacity has been diminishing steadily for the past 40 years.

      Appearances can be deceptive. It's certainly true that by distance Voyager I/II (I assume this is what you are alluding to) has travelled a greater distance than any other mission - but in a sense that is a matter of coasting along and observing what the data tells you. Not to take anything away from Voyager, let me emphasise, it was, and is, an astounding achievement.

      Thank goodness it's not entirely up to them anymore.

      I'm not sure there was ever a time when it was entirely up to them but it seems to me that NASA are the ones doing the interesting stuff at the moment. Sending apes/humans into LEO? Kinda been done before. Sending humans into orbit around Mars? Ummm.. Why? That planet, apart from being generally boring (excluding the possibility of some sort of life there) has already been thoroughly mapped from space by the Mars Orbiter. And we learnt years ago that humans aren't required on locale to make missions work. Hardly groundbreaking stuff.

  3. Re:Pigeons by jaxxa · · Score: 2

    Thats why they have the little space suits.

  4. A link in TFA that I like... by Molochi · · Score: 2

    http://prod.nais.nasa.gov/cgi-bin/eps/bizops.cgi?gr=D&pin=51#154104

    This is NASA's business oportunities page. Very cool...

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  5. Re:Universe-wide network? Is IPv6 sufficient? by TheGratefulNet · · Score: 4, Funny

    and if an atom needs more addresses, it can always run NAT.

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  6. Re:No Money ! by Muad'Dave · · Score: 2

    You ruined that one - the quote is "No bucks, no Buck Rogers!"

    --
    Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
  7. Re:Bad architecture.. by __aaltlg1547 · · Score: 2

    why have a big dish in LEO..

    I meant write GEO, not LEO. The reason is for exactly what you can't get in LEO: a more continuous link to Mars from your ground station. Yes, the earth station uplink antenna and the Earth-orbiting ground-link antenna don't really need to be very big, because the bandwidth is going to be limited by the interplanetary link speed anyway.

    atmospheric attenuation is small (1dB ish) and everything is harder in LEO: power, maintenance, etc.

    Yes, big dish orbiting Mars (doesn't have to be that big.. easier to make the dish(s) bigger on earth than fly it to Mars. 3-4 meters at mars. And a big dish at L2 in a halo orbit that can always see the Earth around the Moon's limb. Or, a bunch of lunar orbiters (with a fair amount of fuel.. it's hard to keep things in a stable orbit at the Moon because the Earth keeps pulling them off path)

    The antenna at Mars pointed at Earth needs to be as big as you can practically make it because received power (therefore bitrate) at Earth is proportional to the product of the dish areas times the transmitter power.

    How much storage should you have and where should it be?

    How do you integrate navigation with this (spacecraft are navigated by precise measurements of the Doppler shift and round trip time delay of the radio signals carrying the data)? DO you have a separate system for nav and data. When you send data at 10 bps, frequency control and measurement to fractions of a Hz was free. But do you really want to control the frequency of your 32 GHz carrier with 1Gbps modulation to that level?

    How do you transfer time from earth to a lander on the back side of the moon or mars?

    Why would you put a 1Gbps link on 32 GHz? I can't think of a good reason to go that high. If you need precise Dopplers, put a slowly-modulated pilot carrier on the link. If you want to get precise time to and from the spacecraft, use two-way time transfer. If you need it on the ground on the back side of the moon, you're going to need orbiters to relay the signals around. On Mars, that's one option, or clocks with more than 12 hour holdover that re-synch when they come back to positions where Earth is visible.

    Also, 1Gbps is pretty out there for interplanetary comms. You would need 100 meter dishes on both ends and a 100kW transmitter.

    Try 100kbps. You can do that with a 10m dish, a 100m dish at Earth and 3kW of transmitter power. (Assuming a typical range of 200 million kilometers. You can turn up the speed when we're closer and would have to turn it down when we're farther away.) Of course, transmitter power from Earth may be not so much of a problem. All the better for the astronauts to get their MTV.