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Orbit trackEdit

Quote [1]: The Chandrayaan 2, on the other hand, was launched to reach the landing site at the beginning of the lunar day, meaning every time it goes over the landing site it will either be dawn or dusk when there are longer shadows. --Dr Nirupam Roy, assistant professor of Physics at the Indian Institute of Science, Bengaluru.

@Ohsin: The orbiter's track shifts with time, and this -according to Roy- explains why the CY-2 orbiter has not imaged the lander optically whenever it is located above the lander. Cheers, Rowan Forest (talk) 00:04, 20 September 2019 (UTC)

CY-2 is in a "polar synchronous orbit" [2]. Is that the same as a "polar Sun-synchronous orbit? Rowan Forest (talk) 00:21, 20 September 2019 (UTC)
Lander deployment occurred just after day-break so lighting conditions would not have been great and being polar region sun elevation is always low anyways resulting in long shadows. But CY-2's polar orbit is in no way fixed to day/night terminator as that quote and news report suggests. Earth's oblateness allows for sun synchronicity in near polar orbits but such synchronous orbit around moon with that altitude and inclination is not possible.  Ohsin  02:16, 20 September 2019 (UTC)
OK, thanks for helping filter out the misinformation. Cheers, Rowan Forest (talk) 03:36, 20 September 2019 (UTC)

"95% Success"Edit

Regarding my revert: the orbiter just entered lunar orbit, so I has not achieved any scientific success yet. A science mission without data return cannot be successful, right? This is another unfortunate misleading statement from Mr. Sivan because of the brevity of his comment. The 95% success refers strictly to the engineering milestones, such as orbiter safe, lander separation, deorbit, and the 4 stages of the descent & landing. I wanted badly to quote him in this correct context, but no publication has explained it correctly. As an example, the European Schiaparelli lander crashed; it was strictly an engineering mission, and since they obtained all the telemetry, it was officially declared a success. The engineering component of the Vikram lander and orbiter may very well be a respectable 95%, but the science part of mission, just got started, and it has yet to report any data. Cheers, Rowan Forest (talk) 23:20, 24 September 2019 (UTC)

@Antares101: Hello. I performed a partial revert of my deletion. Please take a look at this revision and source. Thank you for your patience. Rowan Forest (talk) 13:40, 25 September 2019 (UTC)
I think calling lander/rover mere engineering tests trivializes their importance and work put into them by science/engineering teams, they were not like Schiaparelli EDM which explicitly carried the demonstrator tag. Both were engineering firsts for ISRO but also central to the mission being one of the core objectives, consuming most of the R&D time, costs, causing the launch vehicle switch and most significantly dictating the much discussed landing site. Orbiter was ready 3-4 years ago even contributing hardware to MOM. The reference used has author postulating based on first official statement which has been contended by same author in his later reports. A hypothetical scenario where lander/rover would have survived post separation and orbiter for some reason ceased functioning, even then it could be easily spun into a "98% success" as well! These prompt official statements appear more inclined towards perception management due to high pressure awkward situation they created for themselves.  Ohsin  08:00, 30 September 2019 (UTC)
@Ohsin: I just tweaked the text again. I think it may be useful in dispelling the misinformation in the press, but please feel free to review or even delete the [percentage] entry altogether. I was just trying to accommodate Antares101 edit. Cheers, Rowan Forest (talk) 17:02, 30 September 2019 (UTC)
Scientists tell BBC they contest that number [3]. Delete the entry? -Rowan Forest (talk) 05:28, 1 October 2019 (UTC)
Compiling criticism on claims and handling of situation in case this needs to be included in article.[1][2][3][4][5][6]
Space is hard, but for all the support the Indian media wanted to give to Mr. Sivan, they are catching up to the inconsistencies (potentially false information) so this was unavoidable. Normally, we wait in Wikipedia for the final report stating their conclusions of the failure, and then we create a section dealing with that. But if they are shown to have intentionally released misleading or inaccurate information, then we should complement that future section with the inconsistencies stated by the officials themselves. Rowan Forest (talk) 15:32, 6 October 2019 (UTC)

"Thermal image"?Edit

Lots of news outlets reported, and this Wikipedia article now says, that the lander was located on the surface by thermal imaging. There's just one problem with that: the orbiter doesn't appear to have a thermal camera. The orbiter does have an "Imaging IR Spectrometer" (though whether it's suitable for thermal imaging as well as its purpose of mineral mapping is unclear), and it was suggested to use it to find Vikram, but that has not been reported as having happened, and no such image from it has ever been published, to my knowledge. In the discussion up above (§Clarification needed), there's even a quote from K Sivan saying it was "a normal photo", not thermal. So, can we remove the erroneous mentions of thermal imaging from the article? While the cited sources may be "reliable sources" in general, that doesn't mean they never make mistakes, especially when reporting things secondhand. PointyOintment 💬  02:39, 26 September 2019 (UTC)

I agree, there has been no official comment on it and even K Sivan was vague about method of imaging so perhaps it should not be specified what kind of imagery it was till more details arrive. For what it is worth IIRS might have observed the surface exposed after impact, but we don't have many details on it.  Ohsin  05:59, 26 September 2019 (UTC)
The ISRO sources, whether official or not, are definitely contradictory. I too am OK at removing the word "thermal", and simply state that ISRO claims some sort of imaging was done. Rowan Forest (talk)
Regardless of the technique allegedly used to image its location, why ISRO didn't mention its location? Why it was not shared with NASA's LRO team that is trying to help? NASA's statement mentioned that the lander may not even be in the vast area imaged by the LRO -and it did image the complete plateau and surrounding terrain. Since they still don't know its location, it sounds like the CY-2 orbiter never actually imaged its location, never mind a high resolution image of the "intact lander tilted on its side". Question the answers. Rowan Forest (talk) 17:13, 30 September 2019 (UTC)

Science resultsEdit

I am eager to open the "Science results" section for this article, but as of today, the updates amount to the commissioning of the instruments. If someone comes across published (peer-reviewed) articles on the mission's science, (expected in a few months) please bring them forth so we can document it. After all, this is the main purpose of the mission. Thank you. Rowan Forest (talk) 19:13, 10 October 2019 (UTC)

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