[HN Gopher] 50 Years Later, This Apollo-Era Antenna Still Talks ...
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50 Years Later, This Apollo-Era Antenna Still Talks to Voyager 2
Author : jnord
Score : 173 points
Date : 2024-04-18 22:18 UTC (2 days ago)
(HTM) web link (spectrum.ieee.org)
(TXT) w3m dump (spectrum.ieee.org)
| walrus01 wrote:
| here's an older file with some more detailed info on the
| microwave path loss to/from voyager:
| https://voyager.gsfc.nasa.gov/Library/DeepCommo_Chapter3--14...
| guidedlight wrote:
| There's a fun movie about this particular antenna, starring Sam
| Neill (from another famous historic movie, Jurassic Park).
|
| https://en.wikipedia.org/wiki/The_Dish
|
| Worth a watch.
| Smoosh wrote:
| No, that was about the dish at Parkes, this is about the
| Tidbinbilla dish, near Canberra.
| 78zeros wrote:
| I agree it's a good watch, however they're different antennas.
|
| The radio telescope at Parkes was built prior to DSS-43 that is
| the article's subject, they're located approx. 4 hours drive
| apart.
| jamesbfb wrote:
| Not necessarily related, but it's a fantastic Aussie film
| nonetheless.
| kqbx wrote:
| Dave from EEVblog made a nice series of interviews about this
| station: https://www.youtube.com/watch?v=586Zn1ct-QA
| nullhole wrote:
| Nice link - thanks!
|
| Related, Deep Sky Videos did a series of large-telescope tours
| / interviews a few years back. For example, this is their one
| on Alma; there are a number of others in their channel:
| https://www.youtube.com/watch?v=eAQZp6yTR2Q
| thriftwy wrote:
| A lot of high tech around us is 50 years old now. Some of that we
| would have trouble replacing.
| krallja wrote:
| It's a Dish of Theseus, though. The electronics have been
| replaced, and the dish has been widened. I wonder how much of
| it is actually 50 years old besides the superstructure.
| thriftwy wrote:
| Very often in such projects, The Stuff Not There Anymore is
| visibly contributing to the overall quality of the
| installation.
| mgkimsal wrote:
| I thought I'd noticed this documentary on HN a few weeks ago, but
| I'll re-add it here.
|
| "It's Quieter in the Twilight":
| https://www.imdb.com/title/tt17658964/
|
| Interesting piece on a bit of the history of the Voyagers, as
| well as recent interviews with the handful of remaining folks
| dealing with Voyager today (well, as of 2021/2022).
| jgalt212 wrote:
| Seconded. It was an enjoyable watch for any Voyager fan.
| wglb wrote:
| Also available here https://www.amazon.com/Its-Quieter-
| Twilight-Suzanne-Dodd/dp/...
| uxjw wrote:
| Looks really interesting. Found it free to stream on Plex:
| https://l.plex.tv/mR6jp
| edwarbd wrote:
| If someone wanted to learn antenna design and eventually sigint,
| what resource would you start with?
| subhro wrote:
| You can try to go through the amateur radio extra class.
| wglb wrote:
| Additionally, the ARRL Antenna Book is a great resource:
| https://www.arrl.org/arrl-antenna-book
| zikduruqe wrote:
| That's what turned my law enforcement career into designing
| cellphones for a carrier.
| runjake wrote:
| I would get my ham license and do everything I could with that
| hobby, especially digital.
|
| While doing that I'd either enlist in the US Navy or US Army
| and work my way into a SIGINT job. Once you're in a SIGINT job,
| you'll be far too busy with radio for ham. This would be a fast
| track into SIGINT.
|
| After that I'd use my military career to get into the private
| sector SIGINT world, as there's a well-worn path there.
| NKosmatos wrote:
| We, as a species, need the Deep Space Network(DSN) in order to
| keep communicating with everything man made that's out there
| exploring our neighborhood.
|
| This should be a global effort and I've read many articles about
| the lack of funding for the DSN. It's getting more and more
| difficult to "juggle" and do proper time sharing in order to keep
| communicating with all the existing (and coming) spacecraft.
|
| More resources and funding should be put together, by all space
| agencies (NASA, ESA, JAXA, ISRO...) so as to continue having
| means of communicating with all these space probes.
|
| https://eyes.nasa.gov/dsn/dsn.html
| makerdiety wrote:
| If the global free market doesn't want to spend capital in
| space stuff, then space is probably not worth it. Capitalism is
| an effective filter for economics and resource allocation.
| Soviet Union styled failed management occurs otherwise.
| semireg wrote:
| It's hard for me to understand the arc seconds and degrees. Is
| there some kind of illustration available that shows the
| transmission from earth as a megaphone cone expanding out into to
| space?
| mikewarot wrote:
| Draw an equilateral triangle. The internal angle at a corner is
| 1/6 of a circle, 1.0471975511965 radians.
|
| That can be divided by 60 into _degrees_ , which are
| 0.0174532925199 radians
|
| Those can be divided by 60 into _minutes_ , which are
| 0.0002908882086 radians
|
| Those can be divided by 60 into _seconds_ , which are
| 0.00000484813681109 radians
|
| Those can be divided by 60 into _thirds_ , which are
| 8.08022801849E-8 radians
|
| I think going any further is likely to be meaningless in a
| modern context, but fourths and fifths were used in the past.
|
| https://en.m.wikipedia.org/wiki/Degree_(angle)
| semireg wrote:
| I understand the division of units, what I'd like to see is
| an illustration of the signal's cone at the astronomical
| distances in the article.
| marcosdumay wrote:
| Well, the area taken by a cone with angle "a" at the
| distance "r" is pi * r^2 * sin(a)^2.
|
| For an arcsec, the square sin is ~85e-9. At the distance of
| the Moon, that means the signal occupies ~400km^2. At the
| distance of the Sun, ~5 billions of km^2 (5Mm^2).
|
| The signal intensity is inversely proportional to that
| area.
| semireg wrote:
| For example, if the screw/servo controlling one axis of the
| dish is turned by a minimum adjustment, how many hundreds
| or thousands of miles does it throw the cone's target at
| the distance of the probe? What's the remaining margin for
| error at these scales?
| mikewarot wrote:
| The angle is about 9x10^-5 radians. If you were to take a
| meter stick (or a yard stick) and stick a piece of paper
| under one end, that's the precision within which it can
| point the dish. (While the earth is spinning, and going
| around the sun!) The actual width of the beam is about 5
| times that angle.
| GuB-42 wrote:
| 1 degree = 60 arcminutes, 1 arcminute = 60 arcseconds
|
| One arcminute is about the resolution of the human eye. That
| is, if two points are less than 1 arcminute apart on the your
| field of view, they appear as one point.
|
| The moon is 30 arc minutes (1/2 degree) on your field of view,
| that's why one can see the details of the surface with the
| naked eye.
|
| 18 arcseconds is about the size of Saturn (without the rings)
| as seen from the earth. It means it is just precise enough to
| shoot through the rings of Saturn. You can't see this without
| magnification, like with a small telescope or a good pair of
| binoculars.
| wglb wrote:
| Slightly related, here are radio astronomy antennas:
| https://www.vlba.nrao.edu/sites/SITECAM/
| ooterness wrote:
| For deep technical info on DSN, I highly recommend the DESCANSO
| book series:
|
| https://descanso.jpl.nasa.gov/monograph/mono.html
|
| Thirteen volumes about everything from deep-space tracking and
| navigation to cryogenic low-noise amplifiers, all available for
| free online. It's an amazing resource.
| ilrwbwrkhv wrote:
| Whenever I read stuff like this I find it strange that as a
| species we do this and also kill each other in wars.
| makerdiety wrote:
| Successful space travel and rocket science being a contemporary
| of war and violence is only strange if you find toys to be
| fascinating objects. And didn't a human land on the Moon
| because of a cold war between two superpowers?
|
| What's strange is acknowledgement of the possibility of scarce
| resources necessitating conflict is considered invalid
| criticism that needs to be silenced or given negative reviews
| by the majority opinion. But that's not really surprising when
| things like ascetic religion were created as a reaction to what
| is popularly called criminal or antisocial mental models of the
| world.
| wumms wrote:
| Digital watch for power.
| dramm wrote:
| As a science (and science fiction) nerd kid growing up in
| Australia in the 1970/80s I got a kick out of tracking station 43
| mention in Epilogue 2 of Jeff Wayne's Musical Version of War of
| the Worlds (1978)...
|
| [NASA unmanned landing craft just touches down on mars] [Houston
| Control]: "What's that flare? See it? A green flare, coming from
| Mars, kind of a green mist behind it. It's getting closer. You
| see it, Bermuda? Come in, Bermuda! Houston, come in! What's going
| on? Tracking station 43, Canberra, come in, Canberra! Tracking
| station 63, can you hear me, Madrid? Can anybody hear me? Come
| in, come in!" [instrumental music suddenly stops]
|
| https://www.youtube.com/playlist?list=PLPHEbh7cnr561iJqxno3q...
|
| The Viking missions to mars had started planning in the late
| 1960s and Viking 1 and 2 landed on Mars in 1976 so the inclusion
| of a NASA Mars landing in Epilogue 2 was pretty neat.
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