Mastodawn

AkaSci 🛰️3d ago

Discovery of new extreme trans-Neptunian (TNO) object 2017 OF201.

Large enough at 700 km diameter to qualify as a dwarf planet. Orbit with aphelion of 1,632 AU extends to the inner Oort cloud and covers a region where few extreme TNOs have been detected.

The study used archival data from the Dark Energy Camera Legacy Survey DECaLS using the 4-meter Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile.

https://arxiv.org/pdf/2505.15806
https://en.wikipedia.org/wiki/Extreme_trans-Neptunian_object
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AkaSci 🛰️3d ago

Does the discovery of extreme trans-Neptunian (TNO) object 2017 OF201 suggest a population behind it with 100s of objects with total mass potentially 1% of Earth’s mass?

Does its orbit present a challenge to the Planet X / Planet 9 hypothesis?

Will 2017 OF201 be crowned as a dwarf planet?

I will let the professional astronomers here enlighten us on these weighty questions.
@sundogplanets

https://www.ias.edu/news/extreme-cousin-pluto-possible-dwarf-planet-discovered-solar-systems-edge
https://arxiv.org/pdf/2505.15806
#Astronomy #TNO
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An Extreme Cousin for Pluto? Possible Dwarf Planet Discovered at Solar System’s Edge

A small team led by Sihao Cheng, Martin A. and Helen Chooljian Member in the Institute for Advanced Study’s School of Natural Sciences, has discovered an extraordinary trans-Neptunian object (TNO), named 2017 OF201, at the edge of our solar system.

Institute for Advanced Study

AkaSci 🛰️3d ago

2017 OF201 was discovered from archival data from the Dark Energy Camera Legacy Survey.

The Dark Energy Survey (DES) Collaboration is an international effort to study the properties of dark energy. The DES was conducted using the 4-metre Blanco Telescope at the Cerro Tololo Inter-American Observatory in Chile from 2013 to 2019.

The survey used the Dark Energy Camera (DECam) with a wide field of view ~14x the angular size of the Moon.

https://aasnova.org/2024/10/29/testing-cosmology-with-the-dark-energy-survey-five-year-supernova-dataset/
https://www.darkenergysurvey.org/the-des-project/instrument/
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The following graphic illustrates the extent of the orbit of 2017 OF201 within the Solar system, touching the inner region of the Oort Cloud.

The Oort cloud is a vast cloud of icy planetesimals surrounding the Sun at distances ranging from 2,000 to 200,000 AU.

The NASA Voyager 1 spacecraft, launched in 1977, is currently ~167 AU from the Sun.

1 AU = mean Sun-Earth distance ~= 150 million km.

https://en.wikipedia.org/wiki/Oort_cloud
https://photojournal.jpl.nasa.gov/catalog/PIA17046
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Michael / Chgowiz 🎲🎲3d ago

@AkaSci at first, I was imagining that the image showed the potential that our Oort cloud might overlap Alpha Centauri's... then I realized the image scale was kinda logarithmic. :P

James 🦉 #FBPE 🇪🇺3d ago

@chgowiz @AkaSci Did the same thing! Presume then Alpha Centauri has its own Oort cloud, so does it reach to ours? Do they brush against each other and even exchange objects, or are they still far apart in space's ridiculously vast expanse?

AkaSci 🛰️3d ago

@freequaybuoy @chgowiz

That's an interesting question.

The Oort cloud outermost region is ~200,000 AU from the Sun, i.e., 3.2 light-years.

Alpha Centauri is 4.2465 light-years away.

Alpha Centauri has 3 stars: Rigil Kentaurus (α Centauri A), Toliman (α Centauri B), and Proxima Centauri (α Centauri C). A and B are within 35.6 AU. C is 13,000 AU away from AB.

So the question is whether Alpha Centauri has the equivalent of the Oort Cloud.

https://en.wikipedia.org/wiki/Alpha_Centauri

Alpha Centauri - Wikipedia

James 🦉 #FBPE 🇪🇺3d ago

@AkaSci @chgowiz Thanks! Yes that's the thing, ours seems to reach over half way, but maybe Alpha Centauri doesn't have one, or it's smaller (something to do with a trinary system's formation? And/or the type of stars), or maybe the cloud is shared, a bit like an electron cloud? I realise, like galaxy mergers, Oort cloud objects might be so far apart even when two merge there aren't actually any, or only very few, collisions.

James 🦉 #FBPE 🇪🇺3d ago

@AkaSci @chgowiz Ah ha, this is intersting:

"All this is to say that it isn’t clear how close the Oort Cloud actually gets to the Alpha Centauri system, which is about 4.3 light-years away. Even if the Oort Cloud does stretch halfway to the other system, scientists aren’t sure whether it has its own Oort Cloud."

https://www.astronomy.com/science/ask-astro-does-our-oort-cloud-overlap-with-alpha-centauris/

Ask Astro: Does our Oort Cloud overlap with Alpha Centauri’s?

The Oort Cloud begins about 2,000 to 5,000 AU from the Sun and stretches to about 10,000 to 100,000 AU (0.16 to 1.6 light-years), according to NASA. But keep in mind this outer boundary is pretty nebulous, so there is no hard line where the Oort Cloud ends.

Astronomy Magazine

AkaSci 🛰️3d ago

@freequaybuoy @chgowiz
Also, how do the stars in Alpha Centauri affect the objects in our Oort Cloud? The 3 stars have a combined mass more than two times that of our Sun.

James 🦉 #FBPE 🇪🇺3d ago

@AkaSci @chgowiz Well I think that probably explains comets and other orbital disturbances, eccentricities and anomalies. That article goes on to say, "Likewise, as our nearest celestial neighbor, the Alpha Centauri system likely has some effect, albeit a small one, even at its distance. But Alpha Centauri is actually approaching the Sun. In about 30,000 years, the trio of stars will come within about 2.9 light-years of our star, at which point its influence will be much stronger."

Michael / Chgowiz 🎲🎲3d ago

@freequaybuoy So, theoretically, assuming we don't get Great Filtered out, that could happen within the lifespan of the human species... I wonder what having stars within 2.9 ly will do to our Solar System? @AkaSci

James 🦉 #FBPE 🇪🇺3d ago

@chgowiz @AkaSci Well, if we do make it I'd hope we could nail interstellar travel in that time, at least to our nearest neighbour, if there's a planet worth visiting even colonising, so it would bring it within closer reach to almost the same system or, maybe more likely, our first interstellar war...

Come On Giant Asteroid!2d ago

CAUTION: Log scale

@VE2UWY @AkaSci I was like wtf how is Voyager close to halfway to Alpha Centauri when I noticed the 1 10 100 logscale.

This is why more illustrators/people should take the Tufte workshop so they don't dick with people like that haha.

Come On Giant Asteroid!2d ago

@gahlord @AkaSci

No idea what that workshop is but otherwise ... same.

@VE2UWY @AkaSci You would like it. It's this guy: https://www.edwardtufte.com/book/seeing-with-fresh-eyes-meaning-space-data-truth/?msclkid=858d398f283116cd23c351bc4c796105

Seeing with Fresh Eyes: Meaning, Space, Data, Truth | Edward Tufte

Edward Tufte

Come On Giant Asteroid!2d ago

@gahlord @AkaSci Oh, that guy. Haven't read the book but do know of him.