When at the earliest could we identify a new big dwarf planet ? (This fall already !?!) 😮

[Rabu (Bu Ra)]

I’ve seen in Rubin Observatory Plans for an Early
Science Program RTN-011 Section 3.3 Data Preview 2 :
DRP Solar System Processing (SSP) is currently a stretch goal for DP2. DRP SSP is intended to be a Rubin-only product; meaning that It does not start with the catalog from the Minor Planets Center (MPC).

As you may not know, I am from the public amateur beginner passionate by “giant dwarf planets”.
Funny term isn’t it ?… Yes, in my point of view the “non-giant” dwarf planets (so the regular ones like Haumea, MakeMake, Gonggong, etc.) should not be included in this category of “Dwarf Planets” (where belong, IMO, only Pluto and Eris for the moment), but in a different category of “Giant Asteroids” (don’t ask me why…)

Because of the confusion on knowing exactly what is a planet or not, then we could easily imagine that the actual criteria could be not accurate… And perhaps, in the future we could realise that the true criteria could be others…

Imagine we would discover that there is a kind of a new mathematic démonstration that shows that to be a planet you should have a size bigger than 1800km. Then the Vera Rubin could easily discover new TRUE planets !

And like this Mike Brown would be happy to learn that he is the discoverer of a true planet (Éris) and not anymore just the miserable killer of Pluto and he would be winning with this upgrade !

So it could be of major importance for the Rubin to discover new dwarf planets …and not only the hypothetical Brown’s Planet 9 (him again) that doesn’t exist IMAO…(again, don’t ask me why… but more and more new discoveries tend to confirm my opinion : (2017) OSSOS VI, (2020) Napier & Gerdes, (2025) 2023KQ14, etc.) (And let’s not forget another one’s opinion, the one of the great master David Jewitt, who thinks it’s all wishful thinking…)

Knowing that new dwarf planets would be in majority located around the ecliptic plane, then the SV survey could very well find some (as the SV Survey coverage is mostly the région of the ecliptic (half of it ! : 180 degrees from Scorpio to Aries !)

But!… when will we know about it ?
I imagine that after the detection there must be a Timelapse until we identify its size.
And there is that pipeline process : alarm, brokers, sending to MPC, etc.

But it seems from what I read that with the SV Survey it will be different : …“meaning that It does not start with the catalog from the Minor Planets Center (MPC)”.

So anyone @bechtol @ljones @leanne or others could tell me when and how I could be informed at the earliest that we have identified a new big dwarf planet (only the ones bigger than 1500 km ! So there will be very few !) thanks to the SV Survey ?? (I think we shouldn’t find more than 2 or 3 TNOs bigger than 1500km with the Rubin… So with only the half of the ecliptic (180 deg) and only 10 deg DEC, we should find no more than 1 with the SV Survey…)

Please let me know what will happen next about that topic ! If there’s no transmission to the MPC then what are my possibilities to know about an identification of a dwarf planet during the SV Survey ??
: I am not professional and don’t have access to the Rubin Science Platform…

Should I be asking someone or somewhere each month or even better is there someone who could inform me each month about new identified dwarf planets>1500km ?

[Brnikat (Paul Leyland)]

Seconded. I am also interested in these objects.

[Ron (Ronald ninham)]

Yes, me too. Interesting I’m not in the field, but it is just interesting to me. You have a wonderful day. I would gladly read whatever you have to share. Thank you again.

[Rabu (Bu Ra)]

@Ron

Yes, me too. Interesting I’m not in the field, but it is just interesting to me. I would gladly read whatever you have to share.

Well it’s the field I’m interested in : Solar system. And especially dwarf planets. The rest is not my field (dark matter, stars, galaxies, exoplanets , etc)

As said Mike Brown in an interview : you were part of the cool guys if you were interested in galaxies and stars and you were a loser if you were into the solar system…

I’m definitely a loser… But maybe there’s nothing concerning us in the far cosmos as there is in the solar system… For example, take just the astrologers : they pretend that just the planets of the solar system are influencing us and not the stars…

So what’s interesting in the solar system ?: planet nine (!!) (for the show), NEOs (for the danger) and dwarf planets that could be hypothetical true planets if we came to discover that the actual criteria to be a planet weren’t accurate and that we would find new criteria more accurate ! (For example, my opinion is that to be a planet you don’t have to clean your orbit from other objects ! Then Earth, Neptune and others 2-3 planets wouldnt be considered planets anymore ! So then Pluto and Eris could perhaps be considered true planets in the future… and others discovered soon by the Vera Rubin !)

Well ! Knowing that the dwarf planets should be most of the time near their aphelion, so near the ecliptic(*) and that the SV Survey is focused on the ecliptic (half of it ! 180deg!), and that the SV Survey will reproduce the conditions of the standard survey, (with tracklets), with the IQ (image quality) improving with the calibrations, then almost half of the big dwarf planets that will be discovered by the LSST will be already discovered during the SV Survey ! The coverage is 3600deg^2 ! And in the most interesting part : the ecliptic !

(*): 2/3 of the time a dwarf planet (>800km) with a semi major axis bigger than 50AU (all the closer ones have been detected already) that has then an eccentricity bigger than 0.55, is located in the quarter of the orbit near the aphelion. And the aphelion of far dwarf planets is most of the time near the ecliptic ! Either the orbit has an inclination <20deg and in this case the argument of perihelion is directed in any direction, but anyway the aphelion cant be theoretically higher than 20deg or the inclination is higher, >20deg, but in this case the argument of perihelion tend to lie down at the horizontal ! So even if the inclination is as high of 50deg the aphelion will remain near the ecliptic. And if the object is most of the time near the aphelion, then the object will appear near the ecliptic ! (In 75% of the cases it will be <10deg from the ecliptic and in 95% under 20deg !!)

That means that with the SV Survey we should find already 40% of the big dwarf planets that will be discovered by the LSST ! If we expect to find overall 10 new dwarf planets bigger than 900km, then we should discover 4 of them during the SV Survey !! In august or September already ! It’s there ! At our door ! (And if planet Nine exists… we could find it also these next weeks !! …too bad it doesn’t exist !… )

But because there will be no transmission to the MPC, then how will we be informed that we have identified those objects ?

@Rabu

DRP SSP is intended to be a Rubin-only product; meaning that It does not start with the catalog from the Minor Planets Center (MPC)

No idea. It’s already 1 month that we started the sv survey and we have for sure detected already a few of them ! But probably we haven’t been able to estimate their size yet…

So I will ask again in one month…

But if anyone can give me tips already they’re very welcome !
@nsevilla @mschwamb @bechtol @ljones @leanne
Anyone ?

[MelissaGraham]

Hi @Rabu,

Thanks for your enthusiasm on new dwarf planets! I’ve moved this thread out of our News category and into the Science category, which is the better place for scientific discussions.

Detections by Rubin of all moving objects do go to the Minor Planet Center (MPC). The discovery and confirmation of a big new dwarf planet would be announced with at least a journal publication – similar to the recent publication announcing Rubin observations of the interstellar comet (Chandler et al. 2025).

An accompanying press release and broad advertising would also be likely. So you might even hear about it in the media.

You mention you’re not a professional and don’t have access to the RSP, and that’s ok, as that’s not where announcements happen. Continue to watch the News category here in the Rubin Community Forum, and in addition you might be interested to subscribe and get notifications about new journal articles on topics that interest you: Email subscriptions for new papers - arXiv info.

[ljones (Lynne Jones)]

There are a couple of confusions here:

• The DRP solar system pipeline (SSP) is an independent rubin-only product in that it includes observations from Rubin only, in order to be able to build the science products that let us estimate overall populations and size distributions. That does not mean that discoveries in DRP would not be reported to the MPC.

• Solar System objects will be discovered and linked daily, outside of the DRP, in a separate stage of processing. These databases are useful for following things “live” but are less useful for the population studies I mentioned above, because they also incorporate information from other telescopes (by way of including information from the MPC). This gives us the best chance of getting good orbits to follow things “live” – and is where any new discoveries of the sort you’re interested in will be seen first. These daily processing runs do report back to the MPC, as promptly as possible.

The daily processing will happen as soon as it can.
However, we are a new observatory and we are still gathering data on how well our pipelines work, and also gathering the data we need to do the more complicated processing that SSP needs in order to run. After all, we can’t just find objects in an image without a comparison image to know what was holding still and what was moving – so we need enough comparison images first.

When will you know if we found a new dwarf planet? – this is a bit more complicated and the answer is nobody knows for sure yet. We have to make sure we have enough comparison images; we have to make sure our pipelines are running reliably at the scale that is necessary for a “Rubin-sized” survey; and we then have to make sure we’ve done all of our quality control to release a reliable product. Once we have those pieces in place, we will be sending information to the MPC.

You will know as soon as possible, and it won’t be later than next fall but it will be much more likely to be closer to this fall.

[Rabu (Bu Ra)]

Thank you so much @MelissaGraham for your answer !
Yes youre right , the topic is better in Science section

I’ll check the medias and the community forum in news then.

And I suscribed to the arxiv astro-ph.EP (earth and planetary)

It’s very exciting to see about the comet 3I/Atlas !! It has started with the Rubin ! So… normally in short time we will have a great announcement on a VERY BIG dwarf planet… almost as big as Pluto (~2000km) ! The detection (with 72% chances, if only the object is not over 10deg from the ecliptic, if not we would have to wait for the standard survey for a coverage over -10deg south) should be in august or September, but after… to estimate its size I don’t know how much time it would take… But normally not that much, isn’t it ? It should be a few days (or weeks) isn’t it ?

If so, then we will hear about it in September/October…!!

Watch out !

[Rabu (Bu Ra)]

Oh ! I hadn’t seen your answer @ljones ! I thought it was an old answer of the topic. The confusion came from the splitting of the topic by @MelissaGraham …

Thank you so much too for this detailed answer ! It’s so great to have the possibility to talk with professionals so directly, as with the others observatories or universities it’s very (very) difficult for an external…

I remember you already told me once that you’d probably need a few weeks or months after détection to be able to identify the size… it seems a lot when you realise that I3/atlas has been measured in a few days… And now you say it should be in fall… So thats ok for me, as this is right around the corner !

But you also said that you wondered if such slow objects could be detected… But I’ve been thinking… As the objects we see are moving in general in the same direction than us (from right to left) but we move faster and as we are in situation of opposition, then the object is in a apparent retrograde movement. And yes, in the images they move from left to right. (We can see it with I3/atlas or with the vidéo of all asteroids detected by Rubin shown at the first look.). So, from my point of view, the slower an object moves from right to left (like very distant objects : TNOs far away a>60AU) the fastest it should move in retrograde movement ! Or am I confusing ? Maybe the distance counts too ? (With a close object the retrograde movement is very fast if this object is very slow, but not really if it’s distant ? Thats a question of geometry…) (my intuition is that even if the object is distant, if it’s very slow it should appear with a high speed of retrograde movement… and the only difficulty to detect it should be the brilliance (magnitude)… but thats just an intuition…) (And if I remember well there has already been some astronomer that told me that indeed the characteristics to take in count to determine if a télescope can detect an object is its magnitude only ! Nothing else…)

It’s like 2 trains going one next to the other one. You are in the faster one. You go 100km/h. If the one next to you goes 80km/h it will look like if it was moving SLOWLY in the other direction (backwards), as you don’t feel that you are yourself moving too. But if that train goes slowly, like for example 5km/h only), then it would be moving FAST from left to right (in an apparent movement of retrogradation). So in my interpretation, the slow speed of that object shouldnt be a problem, but just its magnitude… no ? Or maybe - but I don’t think so from what told me an astronomer - if the retrograde movement speed is high, then it could be a problem ? Like if two shots (for a tracklet) are taken in a Timelapse too big (60 minutes) the object would “disappear from the screens” by moving too far ? And we should then take a shorter time lapse like 15 minutes ? I’ve seen that for tracklets the Rubin will use a time-lapse between 15’ and 60’… maybe they will use DIFFERENT time-lapses to adapt to different objects speeds ? I admit I’m ignorant … maybe you or someone else could explain about all that…?

Anyway… we’ll see what kind of dwarf planet the Rubin will detect !

Let’s just sit under the tree and wait and see… until fall

Until the “fall” of the (big) apple (The big dwarf planet )

And like Newton we could learn a lot… (what is aplanet and what is not ?…)

(PS: it’s just too bad the exposure time is so short (30") and that the magnitude will be then limited to 25 (in g band and 24.7 in r band and less in the others) …in perfect conditions !!! (We’re gonna miss a lot of TNOs M>25 ! That will be left to the 40m ELT…). Do you think that an object that has a magnitude of maximum 24.2 should be detected ?… Maybe not if the conditions are not perfect… but maybe there will be nights where the conditions are close to perfection that will allow to detect until >24.2 in g or r bands? Can someone tell ? My intuition again is that if the theoretical limit is 25, then an object of 24 should be detected !… Isn’t it !? And if this intuition is right, then it is very exciting what we would discover… …Suspense !! Soon !! In fall !! Amazing !! It’s there !! Around the corner !
I thought : we discover a new invisible planet every century :
1700s Uranus
1800s Neptune
1900s Pluto (and let me tell you : it’s a planet)
2000s Eris (it’s a planet too, all the rest are just asteroids)
And the next one then it would be in the 2100s… I was afraid of that. But no ! It seems it would be no later than in 3 months ! I’m waiting this since 2006 when we discovered Eris ! Amazing! Get ready ! >1800km diameter (but smaller than 3500km). We’ll never find something bigger than that ever again in the solar system ! …and please forget about the so-called “Planet Nine” ! It’s wishful thinking…)

[CharlesBell]

Since dwarf planets interest you Bu Ra, you may wish to explore the discovery of a new very distant object.

TNO 2023 KQ14 discovery was recently announced in MPEC 2025-G128 : 2023 KQ14
Several observatories were involved: 807 Cerro Tololo Observatory, La Serena, T09 Subaru Telescope, Maunakea, and T14 Canada-France-Hawaii Telescope, Maunakea with their large apertures to reach 25th magnitude.

The absolute magnitude H =6.81 of 2023 KQ14 is much larger implying much smaller size than Dwarf Planets Ceres, Pluto, Eris, Haumea, and Makemake.

2023 KQ14 initial reported observation by Subaru Telescope, Maunakea on 2023-May-16

The discovery was published on July 14, 2025, in Nature Astronomy:
Ying-Tung Chen et al., Discovery and dynamics of a Sedna-like object with a perihelion of 66 au
arxiv preview (https://arxiv.org/pdf/2508.02162)
section 2.3 discusses “Interaction with a hypothetical planet”

There are press releases posted" Astronomers Discover New Distant Object “Ammonite,”
Unveiling Mysteries of Solar System’s Outer Frontier", Released: 15th July, 2025, Academia Sinica Institute of Astronomy & Astrophysics (ASIAA), Taiwan

ASIAA Science Highlights - Astronomers Discover Ammonite

which notes: "Challenges the Existence of Planet Nine"

and https://www.cfht.hawaii.edu/en/news/AmmoniteJul2025/
Ammonite: a Newly Discovered Distant Object that Hints at our Solar System’s Past
which notes: "orbit does not align with those of the other Sedna-like objects and fills the previously unexplained ‘q-gap’ in the observed distribution of distant solar system objects. "

Thanks so much for expressing your interest here.

[Rabu (Bu Ra)]

Oh ! Thank you for your kind feedback (because I feel like a troll around here , but I have to say that’s delightful how all professionals here treat me !)

Yes I had already seen in Google typing “planet nine” about that object.

I was glad it was discovered because this time we could strike a blow against this non-existent Planet 9.

This Planet 9 was overshadowing my beloved dwarf planet too much ! (Which was not fighting in the same weight category ! Batygin the kick-boxer, was cheating, it was unfair !) Nevertheless, it still drew the spotlight on this area of the outer solar system, and it was while watching a documentary on Planet 9 (on Arte TV) that I started studying TNOs… So I owe it a lot.

Now, your object is too distant (“sednoids”) for my subject of interest. I’m looking for the BIG dwarf planet of a dimension similar to Pluto or Eris. Now that planet 9 is “on the ropes” (for the kick-boxer), dwarf planets will gain more interest !! As you don’t need to be big to be a planet !! (the contrary of what is thinking the so called "pluto killer… And, btw, about the size : Pluto has a radius just ~1000km less than Mercury… so… (like : you take your car, you drive ~1000km, and thats the difference of the radius of Pluto and Mercury … Food for thought ! )

Mercury is just the size of USA and Pluto half of it… both are small in comparison with the earth ! Compared to earth there is no significant difference between these two objects !

And until now, I was also interested in TNOs >600km because they were indicators of the possible Semi Major Axis (SMA) of this BIG dwarf planet. For now, I’ve deduced that possible SMAs are 80-83 AU (res 2:9) or 110-113 AU (res 1:7), where we find many TNOs >550km.

But if it were 80-83, we should have found it by now… (its Magnitude would be 20-21…)

This is based on the fact that the (true) planets Pluto and Eris are also accompanied by large TNOs (Pluto: Orcus, Ixion, etc., what we call Plutinos and Eris: Gonggong, 2021 DR15, etc., which we could then call “Erinos”… …so all that’s left is to discover Planet Eleven (and that’s not wishful thinking!) and its… “PlanetElevinos”!

Coming soon! Not only should the Rubin telescope find this “Planet 11” (whose magnitude I estimate at a maximum of 24.2 in the worst case and the limit with the r band is 24.7 and the g band is 25 …in perfect conditions…), but it should also find many of its “Planetelevinos”… (all with a SMA around 110-113 AU) (where you have already an object of 400km, another of 550km and another of 650km)
(and also find others new Erinos the same way, at around 67-68 AU)

Time will say

In fall

Just… Down on the corner !!

[RenuMalhotra]

For Bu Ra: On the Detectability of Planet X with LSST

[Rabu (Bu Ra)]

Thank you so much @RenuMalhotra for that paper

I learned a lot

So an object farther than 75 AU won’t be detected by the standard nightly processing tracking (with the MOPS) because its motion would be too slow and in 30 minutes tracklets we wouldn’t detect it as it would have not reached the motion of minimum 2"/hr.

And the LSST plan is to process only 30’ tracklets…

And to detect it we should use (as long as its magnitude would be lower than 24.5) a special custom processing of one night to the other one (night-to-night processing) with a 24h time lapse (this parameter would allow to detect all objects with V<24.5 that have a motion of >0.04"/hr if I remember well.

So an object of 2000 km (V=23-24) at 180AU would have a motion of 0.8"/hr and it would be ok with a night-to-night. (But not with the standard processing… @ljones was right to doubt about detecting such slow objects)

But I read that it could also be with a time lapse of 2 days or more.

Then there is also the “direct imaging”, LSST Yearly Data…

Can someone help me to understand what is it all about ?

If the LSST won’t process objects farther than 75 AU who will and when ?

I was enthusiastic with the SV Survey we would find very soon (in fall) a possible big dwarf planet… What does it change now with that new parameter ?

Will it extend the delay to find this dwarf planet ?

Will we have to wait May 2026 (release of Data Preview 2) to treat the data of the SV Survey? (Or is that what they call Yearly Data : DP2, DR1, DR2, etc… that you could use for “direct imaging”?) Or are there some users or brokers (like SNAPS Solar system Notification Alert Processing System) that would be able to process the frames with a night-to-night processing before ? (And when exactly ?) @davidtrilling could tell ?

From my understanding, Rubin won’t produce any alert if it doesn’t detect 2 distinct positions of a mobile object (all objects >75AU and <2"/h). And all the frames will be put in the package DP2 which would be released in May 2026 when users will be able to analyze those frames with a night-to-night processing or a direct imaging.
But maybe the frames will be “given” for custom processing to places like “brokers” or other places, before may 2026 ?

Please someone could tell me ?

Maybe the specialists of the solar system at LSST SSSC (Solar System Science Collaboration) :
@ColinOrionChandler @mschwamb or @mjuric
Or anybody else who would know…!
@leanne @ebellm
Or @MelissaGraham could answer or tell me if maybe I should post that question in another section of the forum like in “Support/Data” for @knutago for example ?

Being from the public, amateur beginner, it’s too complicated for me to find the answer by myself. I’ve tried but this is gobbledygook for me, like for example this document :

Data Products Definition Document
LSE-163

I can’t find when the templates/frames/data would be submitted to a custom processing…

Only after DP2 Release in May ?

Or directly during the SV Survey, even if it wouldn’t be done by the LSST (as the LSST will only be processing tracklets of a same night : “nightly processing”) ??? (And like this we would be able to find this dwarf planet already this fall !!!)

Now that we have more and more suspicions on the existence of the fanciful Planet9 it could be a huge achievement to be the discoverer of a big dwarf planet ! Just imagine if we discover the true criteria to be a planet are others than the actuals, you could be the discoverer of one of the planets of the solar system ! Next to legends like Herschel and Galle…