Transmission time per day for Chang'e 4?












4












$begingroup$


Congratulations for the sucessfull landing on the back side of the Moon.



There is continuous line of site available for radio connection from the lander to the Queqiao relay satellite at the Earth-Moon L2 point. But what about the transmission from the relay satellite to ground stations on Earth? Are there antennas on Chinese territory only or is there a global Chinese system, like the DSN system?










share|improve this question











$endgroup$

















    4












    $begingroup$


    Congratulations for the sucessfull landing on the back side of the Moon.



    There is continuous line of site available for radio connection from the lander to the Queqiao relay satellite at the Earth-Moon L2 point. But what about the transmission from the relay satellite to ground stations on Earth? Are there antennas on Chinese territory only or is there a global Chinese system, like the DSN system?










    share|improve this question











    $endgroup$















      4












      4








      4





      $begingroup$


      Congratulations for the sucessfull landing on the back side of the Moon.



      There is continuous line of site available for radio connection from the lander to the Queqiao relay satellite at the Earth-Moon L2 point. But what about the transmission from the relay satellite to ground stations on Earth? Are there antennas on Chinese territory only or is there a global Chinese system, like the DSN system?










      share|improve this question











      $endgroup$




      Congratulations for the sucessfull landing on the back side of the Moon.



      There is continuous line of site available for radio connection from the lander to the Queqiao relay satellite at the Earth-Moon L2 point. But what about the transmission from the relay satellite to ground stations on Earth? Are there antennas on Chinese territory only or is there a global Chinese system, like the DSN system?







      the-moon communication lander china relay






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Jan 5 at 14:36









      uhoh

      35.8k18126447




      35.8k18126447










      asked Jan 4 at 16:18









      UweUwe

      10.1k22954




      10.1k22954






















          2 Answers
          2






          active

          oldest

          votes


















          1












          $begingroup$

          The original of this GIF was tweeted here and I've reconstructed it because I don't know how to post it here (How to show this particular tweeted (GIF?) in a question? - trouble downloading). You can see it is possible to pick up signals even from cubesats at the Moon with a 25m dish (hat tip to @Hobbes), so receiving data from a well-powered and optimized relay satellite like Queqiao would need only a more modest dish.



          enter image description here




          On 7 October, the Chinese lunar satellite DSLWP-B made this 1.5 hour time lapse of the Earth appearing behind the Moon. A team worked hard this week to download the images with the Dwingeloo @radiotelescoop: @bg2bhc, @KuehnReinhard, @ea4gpz, @tammojan, @cgbassa, PE1NUT et al




          You can read more about this dish in





          • https://twitter.com/radiotelescoop (Dutch)


          • https://twitter.com/tammojan (English)


          • https://twitter.com/cgbassa (English)




          China has a satellite communications station in Argentina, which may be useful, and as @GremlinWranger points out tracking ships such as the Yuan Wang-class tracking ships few shown below) if it really needed to extend its geographic stretch. Yuan Wang 2 is shown docked in New Zealand for example.



          While someone is going to say "but the ships are for tracking launches" I'll just say that the ships are for holding antennas, and they can be used to listen to anything that the government would like to use them to listen to.



          From China deploys Yuanwang-7 space tracking ship ahead of Tianzhou-1 cargo mission:




          Yuan Wang 7, constructed by Jiangnan Shipbuilding, is 220 meters in length, 40 meters tall, displaces 25,000 tons, and is said to be able to can resist strong typhoons while operating 100 days at sea, the department said in a statement.



          The ship is said to be the most technologically-advanced watercraft designed by China for the use of space tracking. The vessel features three large dish antennae some 10-12 meters in diameter, and an array of radomes and aerials.



          The Yuan Wang-class ships supplement China's network of land-based tracking stations, which span the breadth of the country's 4,500 km-wide land mass.



          China built its first monitoring ship, the Yuan Wang 1, four decades ago, becoming the 4th nation on the planet to deploy this type of vessel, after the US, Russia and France. Since then, the Yuan Wang fleet has carried out some 70 expeditions, traveling over 1.5 million nautical miles in the Pacific, Atlantic and Indian oceans. Examples:





          • YuanWang-2 Image, Source

          • YuanWang-7 Image, Source







          This video Chinese space tracking ship completes maritime monitoring mission for Tianzhou-1 explains (in English) that the ship tracked the spacecraft in orbit and all the way until Shenzhou-11 docking TianGong-2 space station. So it really is used as a portable "ground" station for communication with spacecraft in Earth orbit, and since Queqiao is really in an Earth orbit (it's not really in orbit around the Moon), it could certainly be used in this case as well.



          All-in-all, there's no reason to expect that communications is limited to the Moon being visible from China's landmass.










          Amateur radio operators listening to Apollo transmissions from the Moon with a modest size dish antenna and 1970's electronics. You don't need a big dish to communicate over 0.0027 AU.



          From Tracking Apollo-17 from Florida, borrowed from the question Why such a large observed doppler shift from Apollo 17 orbiting the moon?



          enter image description here



          This tweet is linked in the article A tiny Chinese satellite is orbiting the Moon and allowing radio amateurs to download images and shows an even smaller antenna can be used to at least pick up a carrier.



          enter image description here



          Borrowed from Help understanding this tweet about receiving images from satellite behind the Moon.





          Borrowed from What will China's new “space station” in Argentinian Patagonia be used for?




          The New York Times (fairly strongly worded) article From a Space Station in Argentina, China Expands Its Reach in Latin America describes a "space station" or base equipped with (among other things) a dish antenna to receive signals from space. The article is long, and well worth a read. Photography is beautiful as well.




          Many more images in @Rob's answer!



          enter image description here






          share|improve this answer











          $endgroup$













          • $begingroup$
            Thanks a lot for this high quality answer. What about the antenna size used on this tracking ships compared to antennas on ground?
            $endgroup$
            – Uwe
            Jan 5 at 13:02










          • $begingroup$
            @Uwe I've added an edit. I would recommend you un-accept my answer and wait for further comments. There's no need to rush!
            $endgroup$
            – uhoh
            Jan 5 at 13:17












          • $begingroup$
            @Uwe I've added a bit more as well.
            $endgroup$
            – uhoh
            Jan 5 at 13:50










          • $begingroup$
            The Dwingeloo radio telescope is not really an example of a "modest dish" though, it's 25 m across.
            $endgroup$
            – Hobbes
            Jan 5 at 20:21






          • 1




            $begingroup$
            The Dwingeloo telescope is no longer in active use by the scientific community, it's been preserved as a monument and run by amateur astronomers and radio hams.
            $endgroup$
            – Hobbes
            Jan 6 at 11:39



















          6












          $begingroup$

          Right now, the Chinese Deep Space Network is only in China, although there are a number of locations there. They are building a station in South America, however, which should give near continuous communication. The setup they have should allow for roughly 16 hours/ day of communication to any deep space object, including Queqiao.



          Note that the Wikipedia article seems to be out of date, the South American station is now operational. As a result, there should be 24 hours/ day possible, during the lunar day.






          share|improve this answer











          $endgroup$









          • 4




            $begingroup$
            According to this article, the station in south America began operation in march 2018. So about 24 hours/day should be possible.
            $endgroup$
            – Uwe
            Jan 4 at 17:24






          • 1




            $begingroup$
            Wikipedia is out of date. Now the question is, do I want to fix it...
            $endgroup$
            – PearsonArtPhoto
            Jan 4 at 18:48






          • 1




            $begingroup$
            We have an answer about the Argentine base. Following the first link leads one to the conclusion that it's operational.
            $endgroup$
            – Rob
            Jan 5 at 0:18






          • 2




            $begingroup$
            They also have these en.wikipedia.org/wiki/Yuan_Wang-class_tracking_ship, Aware of them operating in the Pacific but for this the interesting question would be if one is around south Africa somewhere to match coverage from Argentina.
            $endgroup$
            – GremlinWranger
            Jan 5 at 2:42






          • 1




            $begingroup$
            @Uhoh I believe the website is using AIS en.wikipedia.org/wiki/Automatic_identification_system, unsure if from satellites or ground station aggregation - may be both. They show YuanWang7 near Fiji and claim live data for it. AIS can and is spoofed in various ways but assuming the tracking ships do not get creative so the data is probably accurate (warships not so much). Now sorta curious how much warning you could get for launches by watching the tracking ships.
            $endgroup$
            – GremlinWranger
            Jan 5 at 14:22











          Your Answer





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          2 Answers
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          2 Answers
          2






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          1












          $begingroup$

          The original of this GIF was tweeted here and I've reconstructed it because I don't know how to post it here (How to show this particular tweeted (GIF?) in a question? - trouble downloading). You can see it is possible to pick up signals even from cubesats at the Moon with a 25m dish (hat tip to @Hobbes), so receiving data from a well-powered and optimized relay satellite like Queqiao would need only a more modest dish.



          enter image description here




          On 7 October, the Chinese lunar satellite DSLWP-B made this 1.5 hour time lapse of the Earth appearing behind the Moon. A team worked hard this week to download the images with the Dwingeloo @radiotelescoop: @bg2bhc, @KuehnReinhard, @ea4gpz, @tammojan, @cgbassa, PE1NUT et al




          You can read more about this dish in





          • https://twitter.com/radiotelescoop (Dutch)


          • https://twitter.com/tammojan (English)


          • https://twitter.com/cgbassa (English)




          China has a satellite communications station in Argentina, which may be useful, and as @GremlinWranger points out tracking ships such as the Yuan Wang-class tracking ships few shown below) if it really needed to extend its geographic stretch. Yuan Wang 2 is shown docked in New Zealand for example.



          While someone is going to say "but the ships are for tracking launches" I'll just say that the ships are for holding antennas, and they can be used to listen to anything that the government would like to use them to listen to.



          From China deploys Yuanwang-7 space tracking ship ahead of Tianzhou-1 cargo mission:




          Yuan Wang 7, constructed by Jiangnan Shipbuilding, is 220 meters in length, 40 meters tall, displaces 25,000 tons, and is said to be able to can resist strong typhoons while operating 100 days at sea, the department said in a statement.



          The ship is said to be the most technologically-advanced watercraft designed by China for the use of space tracking. The vessel features three large dish antennae some 10-12 meters in diameter, and an array of radomes and aerials.



          The Yuan Wang-class ships supplement China's network of land-based tracking stations, which span the breadth of the country's 4,500 km-wide land mass.



          China built its first monitoring ship, the Yuan Wang 1, four decades ago, becoming the 4th nation on the planet to deploy this type of vessel, after the US, Russia and France. Since then, the Yuan Wang fleet has carried out some 70 expeditions, traveling over 1.5 million nautical miles in the Pacific, Atlantic and Indian oceans. Examples:





          • YuanWang-2 Image, Source

          • YuanWang-7 Image, Source







          This video Chinese space tracking ship completes maritime monitoring mission for Tianzhou-1 explains (in English) that the ship tracked the spacecraft in orbit and all the way until Shenzhou-11 docking TianGong-2 space station. So it really is used as a portable "ground" station for communication with spacecraft in Earth orbit, and since Queqiao is really in an Earth orbit (it's not really in orbit around the Moon), it could certainly be used in this case as well.



          All-in-all, there's no reason to expect that communications is limited to the Moon being visible from China's landmass.










          Amateur radio operators listening to Apollo transmissions from the Moon with a modest size dish antenna and 1970's electronics. You don't need a big dish to communicate over 0.0027 AU.



          From Tracking Apollo-17 from Florida, borrowed from the question Why such a large observed doppler shift from Apollo 17 orbiting the moon?



          enter image description here



          This tweet is linked in the article A tiny Chinese satellite is orbiting the Moon and allowing radio amateurs to download images and shows an even smaller antenna can be used to at least pick up a carrier.



          enter image description here



          Borrowed from Help understanding this tweet about receiving images from satellite behind the Moon.





          Borrowed from What will China's new “space station” in Argentinian Patagonia be used for?




          The New York Times (fairly strongly worded) article From a Space Station in Argentina, China Expands Its Reach in Latin America describes a "space station" or base equipped with (among other things) a dish antenna to receive signals from space. The article is long, and well worth a read. Photography is beautiful as well.




          Many more images in @Rob's answer!



          enter image description here






          share|improve this answer











          $endgroup$













          • $begingroup$
            Thanks a lot for this high quality answer. What about the antenna size used on this tracking ships compared to antennas on ground?
            $endgroup$
            – Uwe
            Jan 5 at 13:02










          • $begingroup$
            @Uwe I've added an edit. I would recommend you un-accept my answer and wait for further comments. There's no need to rush!
            $endgroup$
            – uhoh
            Jan 5 at 13:17












          • $begingroup$
            @Uwe I've added a bit more as well.
            $endgroup$
            – uhoh
            Jan 5 at 13:50










          • $begingroup$
            The Dwingeloo radio telescope is not really an example of a "modest dish" though, it's 25 m across.
            $endgroup$
            – Hobbes
            Jan 5 at 20:21






          • 1




            $begingroup$
            The Dwingeloo telescope is no longer in active use by the scientific community, it's been preserved as a monument and run by amateur astronomers and radio hams.
            $endgroup$
            – Hobbes
            Jan 6 at 11:39
















          1












          $begingroup$

          The original of this GIF was tweeted here and I've reconstructed it because I don't know how to post it here (How to show this particular tweeted (GIF?) in a question? - trouble downloading). You can see it is possible to pick up signals even from cubesats at the Moon with a 25m dish (hat tip to @Hobbes), so receiving data from a well-powered and optimized relay satellite like Queqiao would need only a more modest dish.



          enter image description here




          On 7 October, the Chinese lunar satellite DSLWP-B made this 1.5 hour time lapse of the Earth appearing behind the Moon. A team worked hard this week to download the images with the Dwingeloo @radiotelescoop: @bg2bhc, @KuehnReinhard, @ea4gpz, @tammojan, @cgbassa, PE1NUT et al




          You can read more about this dish in





          • https://twitter.com/radiotelescoop (Dutch)


          • https://twitter.com/tammojan (English)


          • https://twitter.com/cgbassa (English)




          China has a satellite communications station in Argentina, which may be useful, and as @GremlinWranger points out tracking ships such as the Yuan Wang-class tracking ships few shown below) if it really needed to extend its geographic stretch. Yuan Wang 2 is shown docked in New Zealand for example.



          While someone is going to say "but the ships are for tracking launches" I'll just say that the ships are for holding antennas, and they can be used to listen to anything that the government would like to use them to listen to.



          From China deploys Yuanwang-7 space tracking ship ahead of Tianzhou-1 cargo mission:




          Yuan Wang 7, constructed by Jiangnan Shipbuilding, is 220 meters in length, 40 meters tall, displaces 25,000 tons, and is said to be able to can resist strong typhoons while operating 100 days at sea, the department said in a statement.



          The ship is said to be the most technologically-advanced watercraft designed by China for the use of space tracking. The vessel features three large dish antennae some 10-12 meters in diameter, and an array of radomes and aerials.



          The Yuan Wang-class ships supplement China's network of land-based tracking stations, which span the breadth of the country's 4,500 km-wide land mass.



          China built its first monitoring ship, the Yuan Wang 1, four decades ago, becoming the 4th nation on the planet to deploy this type of vessel, after the US, Russia and France. Since then, the Yuan Wang fleet has carried out some 70 expeditions, traveling over 1.5 million nautical miles in the Pacific, Atlantic and Indian oceans. Examples:





          • YuanWang-2 Image, Source

          • YuanWang-7 Image, Source







          This video Chinese space tracking ship completes maritime monitoring mission for Tianzhou-1 explains (in English) that the ship tracked the spacecraft in orbit and all the way until Shenzhou-11 docking TianGong-2 space station. So it really is used as a portable "ground" station for communication with spacecraft in Earth orbit, and since Queqiao is really in an Earth orbit (it's not really in orbit around the Moon), it could certainly be used in this case as well.



          All-in-all, there's no reason to expect that communications is limited to the Moon being visible from China's landmass.










          Amateur radio operators listening to Apollo transmissions from the Moon with a modest size dish antenna and 1970's electronics. You don't need a big dish to communicate over 0.0027 AU.



          From Tracking Apollo-17 from Florida, borrowed from the question Why such a large observed doppler shift from Apollo 17 orbiting the moon?



          enter image description here



          This tweet is linked in the article A tiny Chinese satellite is orbiting the Moon and allowing radio amateurs to download images and shows an even smaller antenna can be used to at least pick up a carrier.



          enter image description here



          Borrowed from Help understanding this tweet about receiving images from satellite behind the Moon.





          Borrowed from What will China's new “space station” in Argentinian Patagonia be used for?




          The New York Times (fairly strongly worded) article From a Space Station in Argentina, China Expands Its Reach in Latin America describes a "space station" or base equipped with (among other things) a dish antenna to receive signals from space. The article is long, and well worth a read. Photography is beautiful as well.




          Many more images in @Rob's answer!



          enter image description here






          share|improve this answer











          $endgroup$













          • $begingroup$
            Thanks a lot for this high quality answer. What about the antenna size used on this tracking ships compared to antennas on ground?
            $endgroup$
            – Uwe
            Jan 5 at 13:02










          • $begingroup$
            @Uwe I've added an edit. I would recommend you un-accept my answer and wait for further comments. There's no need to rush!
            $endgroup$
            – uhoh
            Jan 5 at 13:17












          • $begingroup$
            @Uwe I've added a bit more as well.
            $endgroup$
            – uhoh
            Jan 5 at 13:50










          • $begingroup$
            The Dwingeloo radio telescope is not really an example of a "modest dish" though, it's 25 m across.
            $endgroup$
            – Hobbes
            Jan 5 at 20:21






          • 1




            $begingroup$
            The Dwingeloo telescope is no longer in active use by the scientific community, it's been preserved as a monument and run by amateur astronomers and radio hams.
            $endgroup$
            – Hobbes
            Jan 6 at 11:39














          1












          1








          1





          $begingroup$

          The original of this GIF was tweeted here and I've reconstructed it because I don't know how to post it here (How to show this particular tweeted (GIF?) in a question? - trouble downloading). You can see it is possible to pick up signals even from cubesats at the Moon with a 25m dish (hat tip to @Hobbes), so receiving data from a well-powered and optimized relay satellite like Queqiao would need only a more modest dish.



          enter image description here




          On 7 October, the Chinese lunar satellite DSLWP-B made this 1.5 hour time lapse of the Earth appearing behind the Moon. A team worked hard this week to download the images with the Dwingeloo @radiotelescoop: @bg2bhc, @KuehnReinhard, @ea4gpz, @tammojan, @cgbassa, PE1NUT et al




          You can read more about this dish in





          • https://twitter.com/radiotelescoop (Dutch)


          • https://twitter.com/tammojan (English)


          • https://twitter.com/cgbassa (English)




          China has a satellite communications station in Argentina, which may be useful, and as @GremlinWranger points out tracking ships such as the Yuan Wang-class tracking ships few shown below) if it really needed to extend its geographic stretch. Yuan Wang 2 is shown docked in New Zealand for example.



          While someone is going to say "but the ships are for tracking launches" I'll just say that the ships are for holding antennas, and they can be used to listen to anything that the government would like to use them to listen to.



          From China deploys Yuanwang-7 space tracking ship ahead of Tianzhou-1 cargo mission:




          Yuan Wang 7, constructed by Jiangnan Shipbuilding, is 220 meters in length, 40 meters tall, displaces 25,000 tons, and is said to be able to can resist strong typhoons while operating 100 days at sea, the department said in a statement.



          The ship is said to be the most technologically-advanced watercraft designed by China for the use of space tracking. The vessel features three large dish antennae some 10-12 meters in diameter, and an array of radomes and aerials.



          The Yuan Wang-class ships supplement China's network of land-based tracking stations, which span the breadth of the country's 4,500 km-wide land mass.



          China built its first monitoring ship, the Yuan Wang 1, four decades ago, becoming the 4th nation on the planet to deploy this type of vessel, after the US, Russia and France. Since then, the Yuan Wang fleet has carried out some 70 expeditions, traveling over 1.5 million nautical miles in the Pacific, Atlantic and Indian oceans. Examples:





          • YuanWang-2 Image, Source

          • YuanWang-7 Image, Source







          This video Chinese space tracking ship completes maritime monitoring mission for Tianzhou-1 explains (in English) that the ship tracked the spacecraft in orbit and all the way until Shenzhou-11 docking TianGong-2 space station. So it really is used as a portable "ground" station for communication with spacecraft in Earth orbit, and since Queqiao is really in an Earth orbit (it's not really in orbit around the Moon), it could certainly be used in this case as well.



          All-in-all, there's no reason to expect that communications is limited to the Moon being visible from China's landmass.










          Amateur radio operators listening to Apollo transmissions from the Moon with a modest size dish antenna and 1970's electronics. You don't need a big dish to communicate over 0.0027 AU.



          From Tracking Apollo-17 from Florida, borrowed from the question Why such a large observed doppler shift from Apollo 17 orbiting the moon?



          enter image description here



          This tweet is linked in the article A tiny Chinese satellite is orbiting the Moon and allowing radio amateurs to download images and shows an even smaller antenna can be used to at least pick up a carrier.



          enter image description here



          Borrowed from Help understanding this tweet about receiving images from satellite behind the Moon.





          Borrowed from What will China's new “space station” in Argentinian Patagonia be used for?




          The New York Times (fairly strongly worded) article From a Space Station in Argentina, China Expands Its Reach in Latin America describes a "space station" or base equipped with (among other things) a dish antenna to receive signals from space. The article is long, and well worth a read. Photography is beautiful as well.




          Many more images in @Rob's answer!



          enter image description here






          share|improve this answer











          $endgroup$



          The original of this GIF was tweeted here and I've reconstructed it because I don't know how to post it here (How to show this particular tweeted (GIF?) in a question? - trouble downloading). You can see it is possible to pick up signals even from cubesats at the Moon with a 25m dish (hat tip to @Hobbes), so receiving data from a well-powered and optimized relay satellite like Queqiao would need only a more modest dish.



          enter image description here




          On 7 October, the Chinese lunar satellite DSLWP-B made this 1.5 hour time lapse of the Earth appearing behind the Moon. A team worked hard this week to download the images with the Dwingeloo @radiotelescoop: @bg2bhc, @KuehnReinhard, @ea4gpz, @tammojan, @cgbassa, PE1NUT et al




          You can read more about this dish in





          • https://twitter.com/radiotelescoop (Dutch)


          • https://twitter.com/tammojan (English)


          • https://twitter.com/cgbassa (English)




          China has a satellite communications station in Argentina, which may be useful, and as @GremlinWranger points out tracking ships such as the Yuan Wang-class tracking ships few shown below) if it really needed to extend its geographic stretch. Yuan Wang 2 is shown docked in New Zealand for example.



          While someone is going to say "but the ships are for tracking launches" I'll just say that the ships are for holding antennas, and they can be used to listen to anything that the government would like to use them to listen to.



          From China deploys Yuanwang-7 space tracking ship ahead of Tianzhou-1 cargo mission:




          Yuan Wang 7, constructed by Jiangnan Shipbuilding, is 220 meters in length, 40 meters tall, displaces 25,000 tons, and is said to be able to can resist strong typhoons while operating 100 days at sea, the department said in a statement.



          The ship is said to be the most technologically-advanced watercraft designed by China for the use of space tracking. The vessel features three large dish antennae some 10-12 meters in diameter, and an array of radomes and aerials.



          The Yuan Wang-class ships supplement China's network of land-based tracking stations, which span the breadth of the country's 4,500 km-wide land mass.



          China built its first monitoring ship, the Yuan Wang 1, four decades ago, becoming the 4th nation on the planet to deploy this type of vessel, after the US, Russia and France. Since then, the Yuan Wang fleet has carried out some 70 expeditions, traveling over 1.5 million nautical miles in the Pacific, Atlantic and Indian oceans. Examples:





          • YuanWang-2 Image, Source

          • YuanWang-7 Image, Source







          This video Chinese space tracking ship completes maritime monitoring mission for Tianzhou-1 explains (in English) that the ship tracked the spacecraft in orbit and all the way until Shenzhou-11 docking TianGong-2 space station. So it really is used as a portable "ground" station for communication with spacecraft in Earth orbit, and since Queqiao is really in an Earth orbit (it's not really in orbit around the Moon), it could certainly be used in this case as well.



          All-in-all, there's no reason to expect that communications is limited to the Moon being visible from China's landmass.










          Amateur radio operators listening to Apollo transmissions from the Moon with a modest size dish antenna and 1970's electronics. You don't need a big dish to communicate over 0.0027 AU.



          From Tracking Apollo-17 from Florida, borrowed from the question Why such a large observed doppler shift from Apollo 17 orbiting the moon?



          enter image description here



          This tweet is linked in the article A tiny Chinese satellite is orbiting the Moon and allowing radio amateurs to download images and shows an even smaller antenna can be used to at least pick up a carrier.



          enter image description here



          Borrowed from Help understanding this tweet about receiving images from satellite behind the Moon.





          Borrowed from What will China's new “space station” in Argentinian Patagonia be used for?




          The New York Times (fairly strongly worded) article From a Space Station in Argentina, China Expands Its Reach in Latin America describes a "space station" or base equipped with (among other things) a dish antenna to receive signals from space. The article is long, and well worth a read. Photography is beautiful as well.




          Many more images in @Rob's answer!



          enter image description here























          share|improve this answer














          share|improve this answer



          share|improve this answer








          edited Jan 6 at 0:00

























          answered Jan 5 at 12:45









          uhohuhoh

          35.8k18126447




          35.8k18126447












          • $begingroup$
            Thanks a lot for this high quality answer. What about the antenna size used on this tracking ships compared to antennas on ground?
            $endgroup$
            – Uwe
            Jan 5 at 13:02










          • $begingroup$
            @Uwe I've added an edit. I would recommend you un-accept my answer and wait for further comments. There's no need to rush!
            $endgroup$
            – uhoh
            Jan 5 at 13:17












          • $begingroup$
            @Uwe I've added a bit more as well.
            $endgroup$
            – uhoh
            Jan 5 at 13:50










          • $begingroup$
            The Dwingeloo radio telescope is not really an example of a "modest dish" though, it's 25 m across.
            $endgroup$
            – Hobbes
            Jan 5 at 20:21






          • 1




            $begingroup$
            The Dwingeloo telescope is no longer in active use by the scientific community, it's been preserved as a monument and run by amateur astronomers and radio hams.
            $endgroup$
            – Hobbes
            Jan 6 at 11:39


















          • $begingroup$
            Thanks a lot for this high quality answer. What about the antenna size used on this tracking ships compared to antennas on ground?
            $endgroup$
            – Uwe
            Jan 5 at 13:02










          • $begingroup$
            @Uwe I've added an edit. I would recommend you un-accept my answer and wait for further comments. There's no need to rush!
            $endgroup$
            – uhoh
            Jan 5 at 13:17












          • $begingroup$
            @Uwe I've added a bit more as well.
            $endgroup$
            – uhoh
            Jan 5 at 13:50










          • $begingroup$
            The Dwingeloo radio telescope is not really an example of a "modest dish" though, it's 25 m across.
            $endgroup$
            – Hobbes
            Jan 5 at 20:21






          • 1




            $begingroup$
            The Dwingeloo telescope is no longer in active use by the scientific community, it's been preserved as a monument and run by amateur astronomers and radio hams.
            $endgroup$
            – Hobbes
            Jan 6 at 11:39
















          $begingroup$
          Thanks a lot for this high quality answer. What about the antenna size used on this tracking ships compared to antennas on ground?
          $endgroup$
          – Uwe
          Jan 5 at 13:02




          $begingroup$
          Thanks a lot for this high quality answer. What about the antenna size used on this tracking ships compared to antennas on ground?
          $endgroup$
          – Uwe
          Jan 5 at 13:02












          $begingroup$
          @Uwe I've added an edit. I would recommend you un-accept my answer and wait for further comments. There's no need to rush!
          $endgroup$
          – uhoh
          Jan 5 at 13:17






          $begingroup$
          @Uwe I've added an edit. I would recommend you un-accept my answer and wait for further comments. There's no need to rush!
          $endgroup$
          – uhoh
          Jan 5 at 13:17














          $begingroup$
          @Uwe I've added a bit more as well.
          $endgroup$
          – uhoh
          Jan 5 at 13:50




          $begingroup$
          @Uwe I've added a bit more as well.
          $endgroup$
          – uhoh
          Jan 5 at 13:50












          $begingroup$
          The Dwingeloo radio telescope is not really an example of a "modest dish" though, it's 25 m across.
          $endgroup$
          – Hobbes
          Jan 5 at 20:21




          $begingroup$
          The Dwingeloo radio telescope is not really an example of a "modest dish" though, it's 25 m across.
          $endgroup$
          – Hobbes
          Jan 5 at 20:21




          1




          1




          $begingroup$
          The Dwingeloo telescope is no longer in active use by the scientific community, it's been preserved as a monument and run by amateur astronomers and radio hams.
          $endgroup$
          – Hobbes
          Jan 6 at 11:39




          $begingroup$
          The Dwingeloo telescope is no longer in active use by the scientific community, it's been preserved as a monument and run by amateur astronomers and radio hams.
          $endgroup$
          – Hobbes
          Jan 6 at 11:39











          6












          $begingroup$

          Right now, the Chinese Deep Space Network is only in China, although there are a number of locations there. They are building a station in South America, however, which should give near continuous communication. The setup they have should allow for roughly 16 hours/ day of communication to any deep space object, including Queqiao.



          Note that the Wikipedia article seems to be out of date, the South American station is now operational. As a result, there should be 24 hours/ day possible, during the lunar day.






          share|improve this answer











          $endgroup$









          • 4




            $begingroup$
            According to this article, the station in south America began operation in march 2018. So about 24 hours/day should be possible.
            $endgroup$
            – Uwe
            Jan 4 at 17:24






          • 1




            $begingroup$
            Wikipedia is out of date. Now the question is, do I want to fix it...
            $endgroup$
            – PearsonArtPhoto
            Jan 4 at 18:48






          • 1




            $begingroup$
            We have an answer about the Argentine base. Following the first link leads one to the conclusion that it's operational.
            $endgroup$
            – Rob
            Jan 5 at 0:18






          • 2




            $begingroup$
            They also have these en.wikipedia.org/wiki/Yuan_Wang-class_tracking_ship, Aware of them operating in the Pacific but for this the interesting question would be if one is around south Africa somewhere to match coverage from Argentina.
            $endgroup$
            – GremlinWranger
            Jan 5 at 2:42






          • 1




            $begingroup$
            @Uhoh I believe the website is using AIS en.wikipedia.org/wiki/Automatic_identification_system, unsure if from satellites or ground station aggregation - may be both. They show YuanWang7 near Fiji and claim live data for it. AIS can and is spoofed in various ways but assuming the tracking ships do not get creative so the data is probably accurate (warships not so much). Now sorta curious how much warning you could get for launches by watching the tracking ships.
            $endgroup$
            – GremlinWranger
            Jan 5 at 14:22
















          6












          $begingroup$

          Right now, the Chinese Deep Space Network is only in China, although there are a number of locations there. They are building a station in South America, however, which should give near continuous communication. The setup they have should allow for roughly 16 hours/ day of communication to any deep space object, including Queqiao.



          Note that the Wikipedia article seems to be out of date, the South American station is now operational. As a result, there should be 24 hours/ day possible, during the lunar day.






          share|improve this answer











          $endgroup$









          • 4




            $begingroup$
            According to this article, the station in south America began operation in march 2018. So about 24 hours/day should be possible.
            $endgroup$
            – Uwe
            Jan 4 at 17:24






          • 1




            $begingroup$
            Wikipedia is out of date. Now the question is, do I want to fix it...
            $endgroup$
            – PearsonArtPhoto
            Jan 4 at 18:48






          • 1




            $begingroup$
            We have an answer about the Argentine base. Following the first link leads one to the conclusion that it's operational.
            $endgroup$
            – Rob
            Jan 5 at 0:18






          • 2




            $begingroup$
            They also have these en.wikipedia.org/wiki/Yuan_Wang-class_tracking_ship, Aware of them operating in the Pacific but for this the interesting question would be if one is around south Africa somewhere to match coverage from Argentina.
            $endgroup$
            – GremlinWranger
            Jan 5 at 2:42






          • 1




            $begingroup$
            @Uhoh I believe the website is using AIS en.wikipedia.org/wiki/Automatic_identification_system, unsure if from satellites or ground station aggregation - may be both. They show YuanWang7 near Fiji and claim live data for it. AIS can and is spoofed in various ways but assuming the tracking ships do not get creative so the data is probably accurate (warships not so much). Now sorta curious how much warning you could get for launches by watching the tracking ships.
            $endgroup$
            – GremlinWranger
            Jan 5 at 14:22














          6












          6








          6





          $begingroup$

          Right now, the Chinese Deep Space Network is only in China, although there are a number of locations there. They are building a station in South America, however, which should give near continuous communication. The setup they have should allow for roughly 16 hours/ day of communication to any deep space object, including Queqiao.



          Note that the Wikipedia article seems to be out of date, the South American station is now operational. As a result, there should be 24 hours/ day possible, during the lunar day.






          share|improve this answer











          $endgroup$



          Right now, the Chinese Deep Space Network is only in China, although there are a number of locations there. They are building a station in South America, however, which should give near continuous communication. The setup they have should allow for roughly 16 hours/ day of communication to any deep space object, including Queqiao.



          Note that the Wikipedia article seems to be out of date, the South American station is now operational. As a result, there should be 24 hours/ day possible, during the lunar day.







          share|improve this answer














          share|improve this answer



          share|improve this answer








          edited Jan 4 at 18:48

























          answered Jan 4 at 16:34









          PearsonArtPhotoPearsonArtPhoto

          81.3k16231445




          81.3k16231445








          • 4




            $begingroup$
            According to this article, the station in south America began operation in march 2018. So about 24 hours/day should be possible.
            $endgroup$
            – Uwe
            Jan 4 at 17:24






          • 1




            $begingroup$
            Wikipedia is out of date. Now the question is, do I want to fix it...
            $endgroup$
            – PearsonArtPhoto
            Jan 4 at 18:48






          • 1




            $begingroup$
            We have an answer about the Argentine base. Following the first link leads one to the conclusion that it's operational.
            $endgroup$
            – Rob
            Jan 5 at 0:18






          • 2




            $begingroup$
            They also have these en.wikipedia.org/wiki/Yuan_Wang-class_tracking_ship, Aware of them operating in the Pacific but for this the interesting question would be if one is around south Africa somewhere to match coverage from Argentina.
            $endgroup$
            – GremlinWranger
            Jan 5 at 2:42






          • 1




            $begingroup$
            @Uhoh I believe the website is using AIS en.wikipedia.org/wiki/Automatic_identification_system, unsure if from satellites or ground station aggregation - may be both. They show YuanWang7 near Fiji and claim live data for it. AIS can and is spoofed in various ways but assuming the tracking ships do not get creative so the data is probably accurate (warships not so much). Now sorta curious how much warning you could get for launches by watching the tracking ships.
            $endgroup$
            – GremlinWranger
            Jan 5 at 14:22














          • 4




            $begingroup$
            According to this article, the station in south America began operation in march 2018. So about 24 hours/day should be possible.
            $endgroup$
            – Uwe
            Jan 4 at 17:24






          • 1




            $begingroup$
            Wikipedia is out of date. Now the question is, do I want to fix it...
            $endgroup$
            – PearsonArtPhoto
            Jan 4 at 18:48






          • 1




            $begingroup$
            We have an answer about the Argentine base. Following the first link leads one to the conclusion that it's operational.
            $endgroup$
            – Rob
            Jan 5 at 0:18






          • 2




            $begingroup$
            They also have these en.wikipedia.org/wiki/Yuan_Wang-class_tracking_ship, Aware of them operating in the Pacific but for this the interesting question would be if one is around south Africa somewhere to match coverage from Argentina.
            $endgroup$
            – GremlinWranger
            Jan 5 at 2:42






          • 1




            $begingroup$
            @Uhoh I believe the website is using AIS en.wikipedia.org/wiki/Automatic_identification_system, unsure if from satellites or ground station aggregation - may be both. They show YuanWang7 near Fiji and claim live data for it. AIS can and is spoofed in various ways but assuming the tracking ships do not get creative so the data is probably accurate (warships not so much). Now sorta curious how much warning you could get for launches by watching the tracking ships.
            $endgroup$
            – GremlinWranger
            Jan 5 at 14:22








          4




          4




          $begingroup$
          According to this article, the station in south America began operation in march 2018. So about 24 hours/day should be possible.
          $endgroup$
          – Uwe
          Jan 4 at 17:24




          $begingroup$
          According to this article, the station in south America began operation in march 2018. So about 24 hours/day should be possible.
          $endgroup$
          – Uwe
          Jan 4 at 17:24




          1




          1




          $begingroup$
          Wikipedia is out of date. Now the question is, do I want to fix it...
          $endgroup$
          – PearsonArtPhoto
          Jan 4 at 18:48




          $begingroup$
          Wikipedia is out of date. Now the question is, do I want to fix it...
          $endgroup$
          – PearsonArtPhoto
          Jan 4 at 18:48




          1




          1




          $begingroup$
          We have an answer about the Argentine base. Following the first link leads one to the conclusion that it's operational.
          $endgroup$
          – Rob
          Jan 5 at 0:18




          $begingroup$
          We have an answer about the Argentine base. Following the first link leads one to the conclusion that it's operational.
          $endgroup$
          – Rob
          Jan 5 at 0:18




          2




          2




          $begingroup$
          They also have these en.wikipedia.org/wiki/Yuan_Wang-class_tracking_ship, Aware of them operating in the Pacific but for this the interesting question would be if one is around south Africa somewhere to match coverage from Argentina.
          $endgroup$
          – GremlinWranger
          Jan 5 at 2:42




          $begingroup$
          They also have these en.wikipedia.org/wiki/Yuan_Wang-class_tracking_ship, Aware of them operating in the Pacific but for this the interesting question would be if one is around south Africa somewhere to match coverage from Argentina.
          $endgroup$
          – GremlinWranger
          Jan 5 at 2:42




          1




          1




          $begingroup$
          @Uhoh I believe the website is using AIS en.wikipedia.org/wiki/Automatic_identification_system, unsure if from satellites or ground station aggregation - may be both. They show YuanWang7 near Fiji and claim live data for it. AIS can and is spoofed in various ways but assuming the tracking ships do not get creative so the data is probably accurate (warships not so much). Now sorta curious how much warning you could get for launches by watching the tracking ships.
          $endgroup$
          – GremlinWranger
          Jan 5 at 14:22




          $begingroup$
          @Uhoh I believe the website is using AIS en.wikipedia.org/wiki/Automatic_identification_system, unsure if from satellites or ground station aggregation - may be both. They show YuanWang7 near Fiji and claim live data for it. AIS can and is spoofed in various ways but assuming the tracking ships do not get creative so the data is probably accurate (warships not so much). Now sorta curious how much warning you could get for launches by watching the tracking ships.
          $endgroup$
          – GremlinWranger
          Jan 5 at 14:22


















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