Talk:Dragonfly (Titan space probe)

Dragonfly, date of original concept conversation
It looks like we're going back and forth on the date of the conversation which initiated this idea. It was originally stated as late 2015, someone changed it to early 2016, on the grounds that he was there, I just took out the date since we don't have a source, and now that's been reverted because "Mission proposal date - 15 months. Very simple math on the reference."

That strikes me as original research (not that I'm a avid fan of that Wikipedia rule), but more to the point, I don't see how it follows so obviously. We're currently 15 months from the next Discovery mission proposal due data, and I can assure you people have been kicking around ideas for over a year. Since we don't have a reference (other than an anonymous "I was there") and it doesn't really seem critical, do we need to specify early 2016? Fcrary (talk) 23:37, 13 January 2018 (UTC)
 * My apologies, Fcrary, I missed the intermediate anonymous edit/claim. The article states 15 months from conversation to proposal. That should do. Thank you. BatteryIncluded (talk) 03:38, 14 January 2018 (UTC)


 * Actually, it's my fault. I missed the 15 month part in the article. Fcrary (talk) 20:30, 14 January 2018 (UTC)

Communications
Does anyone know how the Dragonfly will communicate back with Earth? 65.175.250.233 (talk) 19:32, 15 February 2018 (UTC)


 * Deployable high-gain antenna communicating direct to Earth (DTE) ground stations; this is the disc on top of the vehicle as shown in the infobox image. This is discussed in the article's first reference. ChiZeroOne (talk) 20:00, 15 February 2018 (UTC)

What has been said about the selection of the launch rocket, and any gravity assists
What has been said about the selection of the launch rocket, and any gravity assists ? What mass for the total package (drone, parachutes, heatshield, cruise stage) ? - Rod57 (talk) 09:09, 7 July 2019 (UTC)


 * I don't believe very much has been said about any of that. I have heard, second hand, that there will be a gravity assist and the duration of the cruise phase implies it is not a direct trajectory. But there's nothing I know of we could use as a reference. Similarly, the full launch mass hasn't been stated, at least not as far as I know. For the launch vehicle, the rules of the Discovery program are that missions just specify their requirements (e.g. how much mass to what C3) and NASA will select a launch vehicle for them. That almost certainly hasn't happened yet. Lucy for example, had the launch vehicle chosen two years after the mission was selected. And currently, there is quite a bit of uncertainty in what launch vehicles will be available in 2026. Fcrary (talk) 18:06, 7 July 2019 (UTC)


 * I've also heard that they'll be using a singular earth gravity assist (no Venusian assist as stated currently in the trajectory section)- and that they'll be switching to a yet-undetermined but heavier than planned launch vehicle to accommodate this. They were originally just using a Delta IV Heavy or Ariane V level rocket, but will now need a Falcon Heavy or SLS or something. This was from a NASA engineer working on EDL in an official presentation but I can't find a reputable published source to back it up. Wexford001 (talk) 22:50, 24 August 2021 (UTC)


 * We may know more in a week. There is an OPAG (Outer Planets Assessment Group) meeting on Aug. 30 to Sept. 1, and there is a presentation on Dragonfly's status on the agenda. It may not contain details about the trajectory to Titan; some OPAG presentation do and some don't. But if it does, I believe a presentation at a public meeting, with the slides available online, is a source we can use to update this article. Fcrary (talk) 01:38, 25 August 2021 (UTC)

Air samples
While the article claims DraGNS is going to take air samples as well, as you added January 2018, I could not find any reputable sources that support this claim. Reading about how this instrument is supposed to work (shooting neutrons at the ground) also makes me doubtful this could work in theory, hence I am removing this claim. If you have references to the contrary, I am happy to reconsider. --MGChecker (talk) 00:30, 25 September 2019 (UTC)
 * There is some confusion there. I've heard presentations on Dragonfly which mentioned sampling in flight. But I'm pretty sure the gamma ray and neutron spectrometer wouldn't do that. The statement might have been about one of the other instruments. But until we have a reference, we should probably just leave it out. Fcrary (talk) 06:27, 25 September 2019 (UTC)
 * The only instrument that should be capable to do such analysis would be DraMS. „Novel elements include measurement of atmospheric hydrogen as a possible biomarker“ :4 indicates that air sampling is planned, but I couldn't find further details there. It is claimed that „The system has elements from the highly successful SAM (Sample Analysis at Mars) instrument on Curiosity, which has pyrolysis and gas chromatographic analysis capabilities, and also draws on developments for the ExoMars/MOMA (Mars Organic Material Analyser).“ To quote from the SAM article: „The gas chromatograph (GC) is used to separate out individual gases from a complex mixture into molecular components. The resulting gas flow is analyzed in the mass spectrometer“. Is this solid enough evidence to include this to the DraMS decription? --MGChecker (talk) 10:29, 25 September 2019 (UTC)


 * Hello, my old ID was user:BatteryIncluded. Thank you for the correction. I was aware that DraMS has heritage from Curiosity SAM instrument, which can analyze atmospheric samples. I think I got confused because DraGMet will perform atmospheric profiles, not atmospheric composition. Thanks, Rowan Forest (talk) 16:13, 25 September 2019 (UTC)


 * That's definitely enough to say DraMS can make atmospheric measurements. And that's worth mentioning. I'm still not 100% sure they plan to do that in flight, or if DraGMet has some limited composition capability. But I won't complain if you add something about in-flight composition based on what you've quoted. Fcrary (talk) 19:59, 25 September 2019 (UTC)
 * It is very unlikely they will not analyze the atmospheric composition to some degree, especially while resting on the surface. Unfortunately, the reference above does not state which instrument will analyze the atmospheric hydrogen isotopes for biosignatures. My money is in the DraMS, but the reference does not state it, as if it was an afterthought that they may chose to add such "novel" measurement capability. I'll keep an eye open for updates on that. Rowan Forest (talk) 22:30, 25 September 2019 (UTC)


 * DraMS can definitely measure gas (atmospheric) composition. It's one of a long line of GSFC quadrupole mass spectrometers that have that inherent capability. But their response to hydrogen has been a bit problematic for previous instrument of that sort. But that's not what I'm worried about. The various references to Dragonfly talk about most measurements being made on the surface, when power isn't needed for flight, and limited measurements made in flight. If GraMS is anything like its heritage instruments, it will need a fair amount of power. While it's capable of making measurements in flight, I'm not sure if the power, operational modes and plans really support that. That's what I'd like a reference to confirm. Fcrary (talk) 01:32, 26 September 2019 (UTC)
 * It doesn't have to perform the analysis in mid-flight, just collect a sample for later analysis. Note that the drone will actually spend about 99% of its time on the ground. Think of it as a lander capable of re-locating. But if they wanted a chemical atmospheric profile at different altitudes, they would drop off an atmospheric probe instead of a lander. Rowan Forest (talk) 02:18, 26 September 2019 (UTC)
 * Well, isn't this thing so great because it can both? Of course it spends most of its time on the ground, but they write quite a bit on page 7 about how high than can fly with Dragonfly. They make no statement about chemical profiling there though. However, they do not have to sample all layers of the atmosphere in the same flight, they could do it one after another. --MGChecker (talk) 15:29, 27 September 2019 (UTC)
 * In the presentations I've seen, the team pretty consistently describes Dragonfly as a lander which can move to a different landing site once or twice a month. The flight segments are fairly focused on operations (locating and moving to a new site) rather than science. And I'm not sure how useful one sample/mass spectrum per flight would be. I don't think you could build up an altitude profile from multiple flights. Titan has enough weather than a few weeks and a couple dozen kilometers could make a big difference. — Preceding unsigned comment added by Fcrary (talk • contribs) 21:31, 27 September 2019 (UTC)

Move discussion in progress
There is a move discussion in progress on Talk:Mars Helicopter Ingenuity which affects this page. Please participate on that page and not in this talk page section. Thank you. —RMCD bot 02:18, 2 May 2020 (UTC)

Need for Separate Secondary Payload Page
please a separate titan sample return mission of dragonfly samples is needed as said on this page. http://nasa.gov/directorates/spacetech/niac/2021_Phase_I/A_Titan_Sample_Return_Using_In-Situ_Propellants/ so please create it. —chinakpradhan 19:18, 27 March 2021 (UTC)


 * I've removed the edits to this article on the subject. The reference does not support them. The sample return is a very preliminary concept study and unrelated to Dragonfly. Fcrary (talk) 20:35, 27 March 2021 (UTC)

Will Dragonfly have a watchdog timer like ingenuity helicopter?
I was thinking that like ingenuity helicopter will dragonfly, also have a watchdog timer. The first dragonfly flight is after the release from backshell till landing and I thought if it had a watchdog timer and if it did not transitioned to flight mode then it will impact on titan. I meant since the edl is pre-commanded and so it is obvious that due to edl the dragonfly will separate from backshell, then it will only mean that since at a that time due to watchdog timer, not going into flight mode, it will impact titan in the same way as perseverance and curiosity with skycrane maneuver or without it just simply impact Mars so do anyone knows if the watchdog timer be used on dragonfly? Chinakpradhan (talk) 01:57, 5 May 2021 (UTC)


 * Watchdog timers are standard on every spacecraft I've worked with (which are all NASA planetary ones.) Sometimes each system or processor has its own. But like other sorts of fault protection, a watchdog timer can be disabled. That's not uncommon for critical events, if the consequences of triggering fault protection are serious enough (as they would be during EDL for Dragonfly.) However, I don't know exactly what the plans are for Dragonfly. Fcrary (talk) 15:34, 5 May 2021 (UTC)

Lorenz references - detailed design
Two refs [3]="APL DRAFT" and [20]=":3" are to the same Lorenz pdf and I'll try to share them. But this reference is 2017 or 2018 (pre-selection) and is speculative (pre-design decisions) and we will need to use a later more definitive ref on the actual design. Maybe the design is still evolving ? - Rod57 (talk) 12:49, 27 October 2021 (UTC)

Details to find

 * Battery type, mass, energy
 * Rotor power, flight time, flight speed, distance.
 * Communications bands, power, bit rate, scheduling : communications hours/Titan day ? ...
 * Processor(s), clock-rate, memory (compare to Perseverance?)
 * likely dates for PDR, CDR & decisions.
 * - Rod57 (talk) 12:57, 29 October 2021 (UTC)


 * According to a presentation at the August Outer Planets Assessment Group meeting, https://www.lpi.usra.edu/opag/meetings/aug2021/presentations/Turtle.pdf the PDR will be in September 2022. Fcrary (talk) 18:07, 29 October 2021 (UTC)

statement needs to be nailed down a bit
"similar to early Earth" could be taken by an uninformed reader too far - the differences would have been pretty significant - temperature and exposure to solar radiation alone would have been vastly different 50.111.60.40 (talk) 20:54, 10 July 2022 (UTC)

For how long will the lander be active?
When Dragonfly has landed, for how long time is it supposed to work? It will stand still on the ground during the nights, it's stated, which means it's supposed to fly on Titan for at least several Titan "days", but are we talking of months or even years of functioning? It would be interesting to know, and thus I'm asking. Missions tend to become extended, so I guess nobody knows before, but for Dragonfly's "primary mission"? (Maybe it is in the article already, but then I have missed it.) Fomalhaut76 (talk) 17:56, 14 April 2023 (UTC)


 * 2.7 years (32 months) according to NASA (https://www.nasa.gov/dragonfly/frequently-asked-questions/index.html) Fomalhaut76 (talk) 08:10, 18 April 2023 (UTC)

Regolith
Is the term applicable to such a body? 2A0D:6FC7:43E:F461:9406:68D8:5448:CDD6 (talk) 03:20, 4 December 2023 (UTC)

Requested move 21 February 2024

 * The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this discussion.

The result of the move request was: Moved to Dragonfly (Titan space probe) (closed by non-admin page mover) 🌺 Cremastra (talk) 12:49, 1 March 2024 (UTC)

Dragonfly (spacecraft) → Dragonfly (NASA spacecraft) – Disambiguate from other spacecraft with the same name (Dragon 2 DragonFly, Project Dragonfly (space study) * Pppery * it has begun... 17:19, 21 February 2024 (UTC)
 * Comment I think it would be clearer if we use probe target. Dragonfly (Titan space probe) instead -- 65.92.247.66 (talk) 05:21, 24 February 2024 (UTC)
 * No objection. * Pppery * it has begun... 15:17, 24 February 2024 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.