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China's lunar orbiter captures Earth's images during solar eclipse

Discussion in 'Amateur Radio News' started by AG4YX, Jul 6, 2019.

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  1. WR2E

    WR2E XML Subscriber QRZ Page

    Nahhh.... that's not possible for me! :p

    Seriously though, I do got it now. It wasn't until I remembered that old optical illusion of writing really tall letters on a piece of paper (or the road) and viewing from an oblique angle that I understood that the shadow on the Earth COULD be oblong, yet viewed from the angle of the Moon WOULD look circular.

    I'm sure there are sines, cosines, tangents, etc that could explain it but that would put my synapses to sleep!
     
  2. K3FHP

    K3FHP XML Subscriber QRZ Page

    is it just me, or does the vehicle in image 3 look a lot like the U.S. luner lander circa 1969?
     
  3. KA9Q

    KA9Q Ham Member QRZ Page

    It's not just you, but it's more like 1972 than 1969.
     
  4. KA9Q

    KA9Q Ham Member QRZ Page

    I know sines, cosines and tangents quite well but you don't need them here. The answer is much simpler.

    Consider that you see the very same effect during a lunar eclipse as seen from the earth. The only difference is that the earth is 4x the size of the moon so the moon intercepts only part of the earth's shadow. During the partial phase you see the edge of the earth's shadow on the moon as a circular arc even though it would appear oblong if you looked at it from a different direction in space.

    In both cases the shadow's edges are a little fuzzy because the sun is not a point source. Additionally, during a lunar eclipse we see diffraction of sunlight through the earth's atmosphere, which is not an effect we see in the Chinese picture of the solar eclipse as seen from the moon because the moon has no atmosphere.
     
    KA2CZU likes this.
  5. BG2CTY

    BG2CTY Ham Member QRZ Page

  6. KW0U

    KW0U Ham Member QRZ Page

    Sorry, you can't talk logic to people who think with their emotions. Anything that makes them uncomfortable must be "fake news." It's like a friend who wanted the good old days when America was "great" in the Eisenhower years. I pointed out that then the top marginal tax rate was over 90%. Her answer was simply, "No it wasn't." So a picture like this won't mean anything to someone who already thinks they have all the facts and their mind is made up.
     
    WQ4G, KA9Q, WA8FOZ and 1 other person like this.
  7. KA9Q

    KA9Q Ham Member QRZ Page

    I also like that picture because it shows several of the LM's antennas very well. Besides the steerable S-band dish at upper right, pointed at the earth, there are:

    1. The aft omnidirectional S-band antenna, the small corkscrew helix on the rear surface of the ascent stage just to the left of the right-rear thruster quad. It was used to communicate with earth when the S-band antenna could not be used (e.g., because of blockage by the LM). Its twin is on the "nose" of the LM above the EVA hatch.
    2. The aft VHF antenna is above the S-band omni, on top of the ascent stage. It looks like a quadrifilar with four radials. It was used to communicate with the CSM in lunar orbit. There's another on the top front of the LM, diagonally opposite this one.
    3. Also on top of the LM and to the left of the aft VHF antenna is the VHF EVA antenna. It's the vertical stick with a conical, downward-sloping wire ground plane. It communicated with the astronauts' life support backpacks.
    The LM carried two other antennas that can't be seen in this picture. Both are radars: the landing radar on the bottom of the descent stage, and the rendezvous radar on the top front. It's a steerable dish that closely resembles the steerable S-band antenna on the right side. They're sometimes confused.
     
    KA2CZU likes this.
  8. K4VL

    K4VL Premium Subscriber QRZ Page



    Instead of it becoming space rubbish I find it odd that they have chosen to make it moon rubbish. One day we will be sending convicts up there to clean it up.
     
  9. KC9TNH

    KC9TNH Ham Member QRZ Page

    Just caught this. Thanks W1YW for the photo posting. I'm amazed, as you were, at the quality of the images even the raw one.
    Like many I remember, right before heading to basic training, being enthralled during Apollo 11. This really takes another look at "the Art of the Possible." 47 kilos? Are you kidding me? LOL. That's like launching my grandson into orbit. :)
     
  10. W0PV

    W0PV Ham Member QRZ Page

    The Moon Is a Harsh Mistress - R. Heinlein
     
  11. K5CO

    K5CO Ham Member QRZ Page

    Not only are there NO stars, but the bite taken out of the Earth by the purported moon shadow is the Wrong size/shape. But then, Chinese fake a lot and we should applaud their feeble efforts to gain in the propaganda department (or not).
     
  12. K5CO

    K5CO Ham Member QRZ Page

    Yup! We need to clean up junk left up there so as not harm the local wild life. Not to mention planning to remove carbon dioxide we generate there.
     
  13. K5CO

    K5CO Ham Member QRZ Page

    A good decision!
     
  14. BI8EJM

    BI8EJM Ham Member QRZ Page

    [QUOTE =“N1OOQ,帖子:5121640,会员:823190”]老实说,我有点害怕点击中文网站的任何链接... :伊克:[/ QUOTE]
    why? :(
     
    K7GYB likes this.
  15. BH3MDE

    BH3MDE Ham Member QRZ Page

    It's very spectacular photo, I like this very much, will always pay attention focus
     
    BI8EJM likes this.

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