I never heard Raketenwissenschaft in this context in Germany. Is this a case of anglicism, or are there better suited German synonyms for this expression?
I'd probably say
Das ist doch keine Wissenschaft.
Das ist doch kein Hexenwerk.
LEO's forums contain a few more suggestions (e.g. here).
I wouldn't use Raketenwissenschaft or rocket science in German except when talking informally to peers of whom I know that they know English well enough.
In context of scientific problems, I would say:
Das ist kein offenes Forschungsproblem.
In other contexts I would say:
Das ist machbar.
Das ist kinderleicht.
BTW: I asked for the usage of "That's no rocket science" on EL&U
Nowadays it is common to say
Das ist keine Raketenwissenschaft.
I think it's true, but it has entered German language via English.
The military connotation of "rocket" is a bit more present in German. In English you have "missile" for the weapon, and in German "Mondrakete" for the space-ship (at least in the good old times).
"Raketenangriff" is a common term in todays news, and google translates it as "missile attack". This is pseudo-military in both languages, because it goes from near range to intercontinental.
Now a bazooka is a rocket launcher, it is true. I just found out that the (old) Rak-Rohr I used in the Swiss army was under a Belgian license for a RL-83 Blindicide
missile, also known as a guided missile, is a guided airborne ranged weapon capable of self-propelled flight usually by a jet engine or rocket motor.
So I sometimes spoke of "Rakete" when I meant the ammunition - in a "Rak-Team" one carried (and then fired) the "tube", the other carried (and then loaded) two missiles. This again was confusing to some. But with that tube strapped around my neck, officially called "Rak Rohr", I had a good argument, and there was no better word.
I must add we fired only either small practice calibre or the real size, but without explosive in the tip (just red chalk). It also did not feel like a rocket, it went off with one big explosion. It was not guided.
The new model was tubeless, and suddenly was called "Panzerfaust". I remember that I almost refused to learn a new weapon with such a name. I did not mind using the same kind weapon as the Germans 60 years before, but not if it is called the same - tank fist instead of rocket tube, how wagnerian. Even the Belgian "blindicide" sounds better. Almost.
Das ist keine Hexerei.
This is idiomatic, but it has a slightly different meaning. And also "Hexen" is a little bit vorbelastet.
If a German politician would want to argue in favor of his (complicated) plan, he could say:
Dazu braucht es keine höhere Mathematik.
Meaning: yes, we have to use our brains, but everybody will be able to understand the solution.
It can also be used aginst somebody who is neglecting even simple math (the macht-nach-Adam-Riese kind of math).
This way you have
science (or Mathematik): yes
rockets (or "höhere"): no
funny thing. the rocket science nation doesn't use this expression. Germans use an expression from medival age: Das ist kein Hexenwerk ----
word by word: that's not a witch's work
annotation: "Werner von Braun" deliverd the work to the USA for building rockets to fly to the moon (before he worked for Hitler building rockets to shoot England down)