
Dutch antennas unfolded behind the moon - sohkamyung
https://www.ru.nl/english/news-agenda/news/vm/imapp/astrophysics/2019/dutch-antennas-unfolded-behind-moon/
======
emirp
Why would you put antennas behind the moon?

I read the article: these antennas are radio telescopes (or perhaps just do
the same job). So they're using the moon to block interfering radio signals
from Earth.

~~~
twic
> We have the opportunity to perform our observations during the fourteen-day-
> long night behind the moon, which is much longer than was originally the
> idea.

And from the sun.

> The moon night is ours, now.

That probably sounds less creepy in Dutch.

~~~
edwinjm
"De maan is nu van ons" ;-)

~~~
twic
This reminds me of another instance of Dutch hubris:

[https://beeldbank.rws.nl/MediaObject/Details/Monument__Hier_...](https://beeldbank.rws.nl/MediaObject/Details/Monument__Hier_gaan_we_over_het_tij__de_maan_de_wind_en_wij_406285)

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gus_massa
The satellite is in L2. More details in
[https://www.nature.com/articles/d41586-018-05231-9](https://www.nature.com/articles/d41586-018-05231-9)

~~~
gus_massa
Self nitpicking: It's the Earth-Moon L2, not the Sun-Earth L2. Even more info
[https://en.wikipedia.org/wiki/Lagrangian_point](https://en.wikipedia.org/wiki/Lagrangian_point)

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mirimir
I wonder how the antennas "unfold".

Are they perhaps nested rolled cones of thin metal?

~~~
Triesault
I found a video of the Dutch team testing the 'unfolding' mechanism used in
the NCLE. It looks like a spool that unwinds.

NCLE antenna deployment test - 25x:
[https://www.youtube.com/watch?v=hca3MeX-8rw](https://www.youtube.com/watch?v=hca3MeX-8rw)

Web page with video: [https://www.isispace.nl/projects/ncle-the-netherlands-
china-...](https://www.isispace.nl/projects/ncle-the-netherlands-china-low-
frequency-explorer/)

~~~
mirimir
OK, I get it.

It's like an extreme version of metal tape measures. Which are ~flat when
rolled up, and then curve enough when unrolled to become ~rigid. But in this
case, they seem to become almost cylindrical when unrolled.

I know that it's likely an old design. It's just that I know nothing about
satellite design.

~~~
dbcurtis
Some early Amateur Radio satellites (Project OSCAR) literally did use silver-
plated steel tape measures.

[http://www.rfcafe.com/references/popular-
electronics/oscar-3...](http://www.rfcafe.com/references/popular-
electronics/oscar-3-space-station-popular-electronics-march-1965.htm)

~~~
hughes
Many university-grade cubesats use tape measure antennas today. They can be
easily stored during launch by wrapping them around the satellite body,
secured with nylon fishing wire and then released by burning through the nylon
with a NiChrome heating element.

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unpolloloco
This just reminds me too much of this movie:
[https://m.imdb.com/title/tt1034314/](https://m.imdb.com/title/tt1034314/)

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rozab
Anyone know how and why this Dutch/Chinese collaboration came about?

I know that ESA headquarters are in the Netherlands. Do they just have so much
space funding they have to look outside of Europe?

~~~
greglindahl
The ESA collaborates with everyone all of the time. It’s a great way to get
the best instruments onto each launch opportunity.

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ianai
I appreciate the photos of the antennae. It’s not a critical mission element,
but photos do speak louder than words.

------
based2
[https://www.sciencealert.com/there-s-now-a-radio-
telescope-i...](https://www.sciencealert.com/there-s-now-a-radio-telescope-in-
operation-on-the-far-side-of-the-moon)

~~~
sohkamyung
At the bottom, it says:

> This article was originally published by Universe Today. Read the original
> article.

But it doesn't provide a link to the original article: only to the main
Universe Today website.

