How is this relevant to the Email Reflector
Tower Talk. ????
Steve
KG5VK
On Mon, Jan 21, 2019 at 12:45 PM jimlux <jimlux@earthlink.net> wrote:
> On 1/21/19 9:57 AM, k7lxc--- via TowerTalk wrote:
> > Howdy, TowerTalkians --
> > The recent Chinese moon landing on the dark side has me wondering
> how they communicate from back there. Since we're talking line of sight
> frequencies with no atmospheric scattering or repeater relay capabilities,
> what's going on? Inquiring minds want to know. Tnx!
>
> Relay satellite in a halo orbit at L2. L2 is on the far side of the
> Moon, about 450 million km from Earth (the Moon is around 385 million km
> from Earth)
>
>
> https://en.wikipedia.org/wiki/Halo_orbit
>
> Although we talk about it as a round circular orbit in a plane, in
> reality the orbit is more like the edge of a Pringles potato chip. It's
> not planar. There's a whole family of stable orbits that look like 3D
> lissajous figures.
>
> For what it's worth, there's also Moon libration, and some tall
> mountains near the Lunar south pole.. if you land there, you're
> technically on the far side, but the mountain is high enough to see over
> the edge, helped a bit by diffraction. There's also schemes to use
> diffraction from within Aitken Basin for comm without a relay (perhaps
> in an emergency, if your relay satellite dies)
>
>
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>
>
>
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--
*Steven Lott Smith - Your Candidate for NTX Section manager*
*I will bring more Information & Education to my fellow North Texas ARRL
Members*
*"Education - the way for our Section with active amateurs to have More
fun and Enjoy our great hobby"*
http://sdxa.blogspot.com/
KG5VK Blog
http://www.KG5VK.com
My Ham Radio Friends
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