The topic of this historical paper is an important one, and the entire paper is comprehensive, very well organised and well written. Many successful research programmes and different experiments are described briefly, and a few failures (due to rocket failures). The paper includes 13 valuable and varied figures.

I suggest some detailed improvements.

Line 50. Please change deceased to died.

Line  72,73,110,213,214,216,257,286,376,394.    ... e.g., ...

Line 93. Skua

Line 102. A comprehensive ...

Line 165.   ... mountains.

Line 204.  .. allows us to ...

Line 207. Through ...

Line 241. It would to provide an example or two.

Line 313.   ... scientific ...

Line 352. September

Lin3 405. balloon-borne ...

Line 430. October

Line 432. ... led ...

Line 520. conferences

Line 522. Please change into to as

Review of the manuscript: “History of the Max-Planck-Institut für Aeronomie and its scientific projects (1958-200 4), by Kristian Schlegel

With this history paper, the author, Kristian Schlegel, has done a great service to an institute which emerged out of two unrelated pre-war and wartime activities and settled on a country site far away from the nearest university for reasons of a clean radio sky. The author has adopted a very concise stile, which was most appropriate in view of the great number of activities and projects, in which the MPAe was involved. It is well written and, as far as I can judge, complete with respect to the scientific projects, as promised by the title. However, concerning the scientific activities, there could have been a little more flesh. Of course, this was the author’s decision and what he is submitting is very much worth publishing as is.

What do I mean with flesh? As a reader of this paper one may get a bit exhausted after having tried to digest the enormous number of activities which it is presenting. At one point one may ask: What was great, what was world class? The other aspect I refer to with the word flesh, is a reference to the human interactions or initiatives.  All the projects presented in this history have just been there without an initiator being mentioned. Of course, it would be by far too much to clarify this role with each project. For that purpose, there are many appropriate citations. And in Chapter 4, the role, Ian Axford played in introducing a new way of letting the Institute operate, is well documented. However, it was not made clear that it was also his initiative to attract with Helmut Rosenbauer one of the world-best instrument builders or with Vytenis Vasyliunas one of the best theorists in this field. To my knowledge it was also Ian Axford who attracted Ray Greenwald to build up the STARE radar.

And by the way, in the beginning of Chapter 4 the year of Axford’s very decisive appearance at MPAe was not quoted, only the year in which he had been knighted. Of course, there is a great figure with the dates of all directors at the end of the manuscript.

Another example: On line 413, it is very appropriately stated that the imaging of the nucleus of comet Halley by the HMC camera of H. U. Keller made the MPAe the world-famous. However, there was another outstanding achievement which almost disappeared in the text, the incredible way of the construction of the Rosetta Lander, Philae, by Helmut Rosenbauer. The only mentioning it found was: “build by the MPAe” in line 425 and was not even worth a figure.

I repeat, the paper can be published as is. What I have written above is meant as something for the author to think and possibly act about.

I found two small mistakes: In lines 403 and 423 the plural of spacecraft has to be spacecraft.