User talk:P1X3LZIMMY

2021 RR205 and other orbit updates to TNOs[edit]

Hi P1X3LZIMMY,

I noticed that you are trying to update the orbital elements of TNOs using information from the JPL Small-Body Database (JPL-SBDB) Lookup page. While I do appreciate your intent to keep things up to date, I must let you know that JPL-SBDB isn't very accurate for TNO orbits because it provides them with respect to a heliocentric reference frame--that is, the orbital information is centered about the Sun, which noticeably wobbles around the Solar System Barycenter, which is stationary in contrast. Because the Sun itself is a moving reference frame, the heliocentric orbital elements JPL-SBDB provides changes noticeably over short time scales (or epochs), and that can be problematic when describing orbital elements over the long-term.

For this reason, I ask you to not use heliocentric orbital elements of TNOs straight from JPL-SBDB. Instead, please use barycentric orbital elements from the JPL Horizons On-Line Ephemeris System--that website is much more flexible for obtaining orbital information since you can choose any orbital reference frame and epoch for any minor planet.

I reverted your edits to 2021 RR205 and I'm currently working on revising the 2015 KG163 infobox to include barycentric elements (FYI, a lot of TNO articles haven't been updated to include barycentric elements, I haven't gotten around to doing that...). And one more thing to mention, I noticed you tend to remove the excess spaces in the infobox source, like you did for 2021 RR₂₀₅. Personally, I'm not a big fan of that because it makes the infobox look too compact, which makes it less readable and more difficult to edit in the source editor.

Apologies if my response sounds a bit harsh--I mean no hard feelings, I'm just trying to keep things here in check. If you're unsure about how to cite JPL-Horizons for Wikipedia, see this talk page discussion I brought up last year: Wikipedia talk:WikiProject Astronomy/Archive 34#Using barycentric elements for all TNOs and high-aphelion minor planets/comets. In general, I prefer using an epoch of JD 2460000.5 since it's a recent and nicely round date.

Hopefully you find this helpful. Happy editing!

Nrco0e (talk) 04:21, 5 July 2023 (UTC)[reply]

Oh, thank you! Didn't sound harsh at all, I'm actually very relieved you told me about this, otherwise i probably would've kept on editing them with apparently inaccurate data, and that would not be good. As for the removing spaces, that hasn't been intentional, I currently use the visual editor, so it may be something to do with how that works. Thanks again for letting me know! And thanks for creating and updating so many minor planet articles, I actually recognized your name here! - just checked your userpage and oh my god we have the same the exact same interests!! i can't believe you named an asteroid after Cary Huang, I love their work! That aside, do you have any tips on how to start editing in the source editor? I've been a bit worried to use it out of fear I could just horribly mess it up , but there some articles I've been wanting to make about some interesting rocket designs, since there's no good singular point for them yet, and I'd have to figure out how to put in citations ( both to websites, and books somehow ), so any advice on how to do that would be incredibly helpful! thanks in advance! P1X3LZIMMY (talk) 11:06, 5 July 2023 (UTC)[reply]

No problem. You can learn more about the source editor at Wikipedia:Source editor. In my (clearly biased) opinion, the source editor a lot more flexible than the visual editor, though you'd have to take some time to get used to it. Additionally, you can check out these guides for editing and citing sources on Wikipedia: Help:Editing and User:Nick Moyes/Easier Referencing for Beginners.

Don't be afraid of messing up an article--that's what the revert button in revision history page is for after all. The article's history page allows you to see how each edit has changed the article's source, which is very nifty for picking out mistakes using the source editor. If you're still hesitant about making changes to a page, you can always resort to copying the artice's entire source and pasting it in your own sandbox page where you can safely experiment edits without disrupting the original article.

Nrco0e (talk) 02:08, 6 July 2023 (UTC)[reply]

Alright, thank you! I'm going to try to update the orbit of 2003 QW111/Manwe-Thorondor (personal favorite KBO) through the source editor, and using Horizon based at the solar system barycenter

P1X3LZIMMY (talk) 12:06, 6 July 2023 (UTC)[reply]

26P/Grigg–Skjellerup[edit]

P1X3LZIMMY, what was the source that 26P/Grigg–Skjellerup is coming to perihelion in Feb 2024 instead of Christmas day 2023? I am curious if a well known website has the date listed wrong so that I can notify them to correct it. -- Kheider (talk) 11:00, 26 July 2023 (UTC)[reply]

https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%2790000375%27&TABLE_TYPE=%27ELEMENTS%27&START_TIME=%27JD2460000.5%27&STOP_TIME=%27JD2460200.5%27&STEP_SIZE=%271y%27&CENTER=%27@0%27&OUT_UNITS=%27AU-D

I took the perihelion date listed there (JD 2454549.21359 / March 23, 2008) and added the orbital period until i got a date in the future (2454549.21359+((5.295708272*365.256363)*3))=JD 2460352.08702 / February 11, 2024.

You can also see on the JPL Horizons orbit visualizer that perihelion is around that time, which is actually how i first noticed the date was wrong, then i made sure to check the proper horizons orbital stuff to confirm. I don't think its any website wrong, could've just been an outdated epoch or some old calculation from years ago P1X3LZIMMY (talk) 11:14, 26 July 2023 (UTC)[reply]

The solution definitely needs to propagate the orbit away from the 2008 perihelion passage (3 apparitions ago) to get the correct date of perihelion. This link https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%2790000375%27&START_TIME=%272023-Dec-20%27&STOP_TIME=%272024-Feb-11%27&STEP_SIZE=%273%20hour%27&QUANTITIES=%2719%27 shows the comet 1.08 AU from the Sun on 2023-Dec-25, but 1.25 AU from the Sun on 2024-Feb-11. The "orbit visualizer" is basically worthless for determining any dates. -- Kheider (talk) 11:41, 26 July 2023 (UTC)[reply]

do you know how to get horizons to show a more recent epoch then? that one was the most recent that popped up in the list of epochs P1X3LZIMMY (talk) 11:46, 26 July 2023 (UTC)[reply]

Horizons (and the JPL SBDB) will often pick a non-current epoch solution that is a generic best-fit for several different epochs. Your epoch of 2023-Feb-25 was usable enough, as JD 2460303.9 (from your source) converts to 2023-12-25. I think the problem was assuming the "orbit visualizer" was useful more than a few days/months away from epoch 2010. -- Kheider (talk) 12:08, 26 July 2023 (UTC)[reply]

Oh! I didn't assume the orbit visualizer was useful, thats why I checked horizons to make sure! I think my mistake was maybe adding the orbital period instead of checking the readout, that probably added a decent amount of error, no way 26P's orbital period was the exact same over 3 orbits, pretty decent mistake on my part, I'm sorry for that. P1X3LZIMMY (talk) 12:27, 26 July 2023 (UTC)[reply]

We are all here to make Wikipedia more useful. I am glad we got that figured out. When you first posted it, I had to wonder if I had overlooked something myself. It happens. -- Kheider (talk) 12:37, 26 July 2023 (UTC)[reply]