Pluto is just too
2 Likes
Yeah, no, I donât think it is. I mean, sure, they wonât care about clearing its orbit as suchâŚbut the fact that it didnât do so has strong implications about how it formed, what other objects it is like, and how it fits into the structure of the solar system. It very clearly goes with it being in the same category as things like Haumea and Triton rather than things like Neptune or Earth all the ways that a planetologist should care about.
1 Like
Junking orbital junk? The mind behind ASTRIAGraph database project hopes to âmake space transparentâ
1 Like
Thatâs a mass based defintion. Fine for Schwarzschild black holes, but thereâs more to those bodies than mass.
Thereâs a theory that Triton originated in the Kuiper belt and was captured by Neptune.
Neptuneâs capture of its moon Triton in a binaryâplanet gravitational encounter
1 Like
Yes, but I said there was more to it than mass too, although itâs clearly not a coincidence that an order of magnitude gap happens at exactly the same place as with orbit clearing measures. And that Triton was very likely captured from the Kuiper beltâŚas in, you can tell in part because it has similar properties to the objects thereâŚis exactly the sort of thing I was talking about and even mentioned. 
1 Like
I once read a book on dark matter in which the author, an astronomer, criticized the use of astronomical facilities and budgets to essentially solve physics problems. Yes, it is possible to use astronomy to nail down the rate of cosmological expansion, and figure out dark matter/ dark energy-- but those arenât the only astronomy problems; theyâre just the ones that excite physicists and politicians.
The idea of pluto as a major planet, or as a dwarf planet has political implications. A major planet seems on itâs face to be worthy of more than a flyby, a minor planet has to fight for it. Uranus seems like a likely candidate for an orbiter, because it is a major planet, but itâs also described as fairly boring. The fact that it has cleared its orbit does not make it interesting to the folks who would actually take scientific advantage of close observations.
In part because there are a lot more dwarf planets out there, and I can see whether one visits Haumea or Makemake or Pluto or Eris being a question of expediency more than anything. To a proper scientist, though, they would all be examples of a category of objects we barely understand and should learn more about. If you really think theyâre worth investigating, which I do, maybe it would be better to convince people of that than lie about whether one in particular fits with the all the others, which I assume you would then neglect accordingly.
By the way, Uranus might or might not be fairly boring, but Iâm not convinced Miranda, Ariel, Umbriel, Titania, and Oberon all are. Are you really not interested because they exist there by orbiting a much larger mass and so are called moons?
In any case, though, taxonomists organize life into animals, plants, fungi, protists, and prokaryotes, not into economically important, charismatic, and who cares. The idea that how we describe and organize the natural world should not be an attempt to best capture what is out there, to make it understandable for pedagogical purposes, or to provide a framework for answering questions, but simply to talk certain things up for political reasons is so anathema to me that I donât think I can argue against it.
Just compare: Pluto, which could be considered a planet, has varied terrain, which in suggesting as a planetary feature you are clearly taking that as something specific to it; or Pluto, the first Kuiper belt object seen up close, has varied terrain, which is both interesting in itself but also encourages questions about the others.
I mean, this is a dead argument and I shouldnât be indulging in it. But I was so happy back when Pluto was reclassified, because it reflected a new understand of the solar system, one which was a long time coming and has gone with a ton of exciting new discoveries. And then it turns out people canât be bothered to care about any of that, just whether Americaâs world has the special âstatusâ they learned in school, and itâs so frustrating to see still hammered on.
Archaea, Bacteria and Eukarya is pretty popular.
Itâs probably possible to sort this list by NSF grants
List of model organisms - Wikipedia
and come up with a result that does not reflect taxonomic diversity.
It is, but thatâs not actually in disagreement with what I said since Archaea and Bacteria are the two domains of prokaryotes. And various new research has suggested there is in fact a single ancestral domain, with Bacteria giving rise to the others somewhere near Plactomycetes. In which case that may not be the best way to separate them, which is why I didnât go into that.
Now does any of that actually have anything to do with what we were saying, or are you just trying to score pedantic points for their own sake? Because if so, Iâm kind of disappointed they keep being things I already know. 
1 Like
Interesting paper! Thanks.
3 Likes
Planetary Mission Concept Study: Persephone A Pluto System Orbiter and Kuiper Belt Explorer
Persephone is a concept mission study that will address key questions raised by New Horizonsâ encoun- ters with Kuiper Belt objects (KBOs), with arguably the most important being âDoes Pluto have an ocean?â which has critical astrobiological impacts. More broadly, Persephone will answer three significant science questions: What are the internal structures of Pluto and Charon? How have the surfaces and at- mospheres in the Pluto system evolved? How has the KBO population evolved? The questions we ad- dress here directly contribute to four Key Questions (KQs) and six Important Questions (IQs) outlined in the 2013â2022 Planetary Science Decadal Survey (PSDS; Vision and Voyages, 2011). Although not a driver for this study, we note that because of the nature and payload of this concept mission, the final mission would also address two Key Goals (KGs) from the Heliophysics Decadal Survey (SSP, Solar and Space Physics, 2013).
NEPTUNE ODYSSEY: Mission to the Neptune Triton system
The Neptune Odyssey mission concept is a Flagship-class orbiter and atmospheric probe to the Nep- tune-Triton system. This bold mission of exploration would be the first to orbit an ice giant planet to study the planet, its rings, small satellites, space environment, and the planet-sized moon, Triton. Triton is itself a captured dwarf planet from the Kuiper Belt and a geophysically reactivated twin of Pluto. Odyssey addresses Neptune system-level science, with equal priorities placed on Neptune, its rings, moons, space environment, and Triton. Between Uranus and Neptune, the latter is unique in providing simultaneous access to both an ice giant and a Kuiper Belt dwarf planet. The spacecraftâ in a class with Cassiniâwould launch in 2033 on a Space Launch System (SLS) or equivalent launch vehicle on a 16-year cruise to Neptune for a 4-year prime orbital mission. The defined solution pro- vides annual launch opportunities and allows for easy upgrade to a shorter (12-year) cruise phase that can utilize a Jupiter gravity assist (JGA), if NASA chooses to stand up this mission in time for a launch before 2032. Odyssey would orbit Neptune retrograde (prograde with respect to Triton), providing New Horizons-quality science from Triton every month, using the moonâs gravity to shape the orbital tour and allow coverage of a range of latitudes and longitudes on Triton, on Neptune, and in the space environment. The atmospheric entry probe would descend in ~37 minutes to the 10-bar pressure level in Neptuneâs atmosphere just before Odysseyâs orbit-insertion engine burn. Odysseyâs mission would end by conducting a Cassini-like Grand Finale tour, passing inside the rings very close to the giant planet, and ultimately taking a final great plunge into Neptuneâs atmosphere.
There are also proposals for Enceladus, and Titan, but I canât find the pdfs.
1 Like
4 Likes
1 Like
This way up: James Webb Space Telescope gets ready for shipment after final tests
Itâs been a big week for the much-delayed James Webb Space Telescope (JWST) as testing of the observatory was completed and operations to ship the spacecraft to the Kourou launchpad began.
[âŚ]
3 Likes
Perseverance to take a second stab at Martian rocks ⌠but first it has to scratchânâsniff
NASAâs Perseverance rover will make a second attempt at collecting a sample of Mars rock for eventual return to Earth â though itâs going to scratch its latest target first to make sure itâs worth bothering.
[âŚ]
2 Likes
