Talk:Mars cycler/GA1

GA Review

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Reviewer: Balon Greyjoy (talk · contribs) 02:19, 29 December 2018 (UTC)[reply]

Is it well written?
A. The prose is clear and concise, and the spelling and grammar are correct:
Lead
Remove 'special' when describing the trajectory. I think it is clear that these orbital trajectories are useful for an Earth-Mars cycle.
Done Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

Earth–Mars cyclers
You use 'on a regular basis' twice in the first two sentences. I would remove it from the second sentence.
Y Removed. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

"The use of cyclers was considered in 1969 by Walter M. Hollister, who examined the case of an Earth-Venus cycler." This comes across as confusing. Was he considering it for a specific mission for NASA/JPL, or did he publish a paper/article recommending it as an option?
Y Added that he was not considering any particular mission. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

Hollister was not considering any specific mission, but posited the

I would use a single sentence to describe the synodic period between Earth and Mars, explaining the 8:15 orbital ratio. Then I would explain how the Mars cycler options take place in multiples of the period.
Y Swaps the sentences around. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

"It travels from Earth to Mars orbit in 146 days, spends the next 16 months beyond the orbit of Mars, and another 146 days from the Martian orbit back to Earth." Correct me if I'm wrong, but my understanding is that these cyclers only allow for flybys, and the cycler spacecraft itself wouldn't be entering Martian orbit. This sentence makes it sound like the cycler spacecraft orbits Mars at two separate times in its trajectory, and then spends the rest of its time in heliocentric orbit.
Y Oh no, but there is a clear confusion of "orbit"s here. Tried to make it clearer. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

I would use full names and a minor job description for Russell and Ocampo, instead of just using their names as you would in a citation.
Done 07:10, 30 December 2018 (UTC)

It seems a little extraneous to mention the non-ballistic cyclers, as the point of the cycler is the minimal use of energy when travelling between two bodies.
The comparison though, is between cyclers and transfer orbits. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

Physics
It's a little confusing how the first sentence introduces a conic section equation, ends with a colon, and then launches into another paragraph before getting into an equation.
Y Ooops. Looks like the sentence got move when we were fiddling with the images. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

This section reads like a textbook instead of an encyclopedic entry in certain sentences, with phrases such as "gives us," and "we have," and "we can". I couldn't find any guidance on this, but looking at other physics pages had the more objective-type phrases that you also use, such as "calculated from." You are a much more experienced Wikipedia editor, so I am hoping that you have some thoughts on the matter.
I like to be taken step by step through calculations. So at least I understand it. I have tried to make it read more formally. I used to have these orbits down pat when I was a UG. (Buzz's PhD thesis is very readable btw) Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

Theoretical usage
"While the astronauts travelling to the Moon could do so in a small spacecraft, a mission to Mars would require something much larger. Astronauts would need a much larger facility with life support, living space and radiation shielding for the much longer journey." I would combine this in to one sentence, and just state the needs for a large facility, and that this spacecraft would be much larger than a spacecraft to go to the moon (I prefer using relative terms vs. absolute terms, as a S-IVB and CSM is definitely not a small spacecraft).
Y Changed to relative. The habitable space was the CM and LM ascent stage. Not a whole lot of room. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

I would mention that mass that would be needed to go to Mars, but remove the cost description, as that has changed, and will (hopefully) continue to be lowered by the time any such cycler would exist.
Y removed. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

"The problem of getting the castles into cycler orbits was also considered." This seems redundant to include, as all problems for the cycler would have to be considered at some point before it could be possible.
Y Removed. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

" It was found that this could be accomplished with considerable savings in fuel by performing a series of low thrust maneuvers." Make the castle the subject of the sentence, and say how it would perform low thrust maneuvers to conserve fuel.
Done Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

Further explain the different types of thrusters needed, as you mention the low-thrust maneuvers, and then launch into the two different types of fuel combinations with no explanation of why one would be used at a given time.
Y It's a little awkward, but added. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

"it is possible to estimate the fuel required to establish a cycler obit" This is unnecessary to include, as the fuel usage would certainly have to be calculated before a castle could launch and enter the cycler orbit.
Sure, but the reader is given a calculation of fuel usage. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

I would either remove the part about the VISIT-1 trajectory and its relatively little benefit, or explain how much extra life support material would be necessary to support an addition 3 years of mission time.
None is required. I prefer to think of the castles as buses, where the astronauts hop on an off. No life support is required until the astronauts are on board. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

B. It complies with the manual of style guidelines for lead sections, layout, words to watch, fiction, and list incorporation:
No concern. Any wording issues were brought up in the previous section.
Is it verifiable with no original research?
A. It contains a list of all references (sources of information), presented in accordance with the layout style guideline:
No concern, but my personal preference for a reference section would be to have in-line citations that link to the reference section, vs. a notes section with the citations, and a reference section with the source information.
I always use this form. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

B. All in-line citations are from reliable sources, including those for direct quotations, statistics, published opinion, counter-intuitive or controversial statements that are challenged or likely to be challenged, and contentious material relating to living persons—science-based articles should follow the scientific citation guidelines:
No concern.

C. It contains no original research:
No concern.

D. It contains no copyright violations nor plagiarism:
No concern. Earwig link

A. It addresses the main aspects of the topic:
No concern.

B. It stays focused on the topic without going into unnecessary detail (see summary style):
No concern. I was surprised with how short the article was at first, but it covers everything appropriately, in my opinion.
Is it neutral?
It represents viewpoints fairly and without editorial bias, giving due weight to each:
No concern.
Is it stable?
It does not change significantly from day to day because of an ongoing edit war or content dispute:
No concern.
Is it illustrated, if possible, by images?
Nice job on making your own diagrams; it's my first time reviewing them on a page!

A. Images are tagged with their copyright status, and valid fair use rationales are provided for non-free content:

B. Images are relevant to the topic, and have suitable captions:
I think the Buzz Aldrin picture should be moved lower to the Aldrin cycler section.
I like him here as an ersatz infobox. He looks very professor-ly here, don't you think? Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]
I disagree on him being at the top of the article as an infobox, but that's just a matter of opinion, and doesn't detract from the article in any way.

I find the orbital diagrams that you made slightly confusing unless they are zoomed in, but I don't think there is a better way to illustrate the Mars cycler orbits.
Could be our different screen sizes. What I would have liked to have done is construct animated versions of the diagrams, but it's rather more difficult. I have asked the Graphics lab for assistance. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]
Seems to me like you are suggesting that I order a larger monitor. I don't want to buy one, but if I have to for the sake of Wikipedia... But seriously, I think an animated version would be very beneficial. Unfortunately, I do not know how to make one, but I'm sure it is not an easy process.
People sometimes complain about layouts, saying that they are sseing white space, and it doesn't occur to them that other people are seeing the page differently. To see exactly what they are seeing, I need to know the platform, browser, monitor resolution and skin they are using so I can duplicate it. But usually their answer is: "what?"

The animations need to be constructed programmatically, generating hundreds of frames and then merging them together with a graphics package. I tried using a Perl script with GL. I got as far as animating the orbits of Earth and Mars, which are simple because they are circular. The cycler is much harder because it elliptical and therefore travels at different speeds at different parts of the orbit, and my cycler was not meeting the planets when it should have. Or you could use a numerical package like MATLAB which would do both at the same time. Hawkeye7 (discuss) 23:31, 30 December 2018 (UTC)[reply]

Thoughts on using alt text to explain the M1-4 and E1-4 points on the two-ship cycler diagram

I don't think the gravity assist velocity diagram adds much to the section, as it doesn't provide a clear depiction of the way velocity is gained or lost through an encounter with a large body. Similar to the orbital diagrams, I don't know if there is a simple way to illustrate it, but I find the depiction of the trianagle with the different variables to be a bit of an eye-chart.
I kept referring to it in order to follow the equations. Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]
Overall:
Pass or Fail:

I have completed my initial review and will be placing the article on hold. I will be available to answer any questions or address any comments. Nice job on this article! Balon Greyjoy (talk) 09:54, 29 December 2018 (UTC)[reply]

Thanks for your review! (Balon Greyjoy sounds like a Games of Thrones character.) Hawkeye7 (discuss) 07:10, 30 December 2018 (UTC)[reply]

Drive-by comment: dashes in the citations should be endashes. Sidenote: I also have a couple other Longuski books, they are good, casual books to read. He teaches senior design, I took it from the other professor that teaches it though. Kees08 (Talk) 20:06, 30 December 2018 (UTC)[reply]

I fixed the endashes. Balon Greyjoy (talk) 22:59, 30 December 2018 (UTC)[reply]

It is! Balon Greyjoy is Theon Greyjoy's father. Balon Greyjoy (talk) 22:59, 30 December 2018 (UTC)[reply]

Aha! Hawkeye7 (discuss) 23:31, 30 December 2018 (UTC)[reply]

@Hawkeye7: Nice job getting the fixes done promptly. We disagree on a few stylistic choices (cough...book citations...cough), but I think that you have done a great job on this article. Happy to pass it! Balon Greyjoy (talk) 22:59, 30 December 2018 (UTC)[reply]