The Edges of the Solar System

May 07, 2010
An image of Triton, the largest moon of Neptune. Triton is thought to be a Kuiper Belt Object captured by Neptune. Credit: NASA; Voyager 2

(PhysOrg.com) -- The solar system does not end abruptly past the planets. Beyond the orbit of Neptune, the outermost planet (it orbits the sun at a distance of 30 AU, where one AU is the average distance of the earth from the sun), lies the Kuiper Belt, a region of many, small icy bodies that extends out well beyond 130 AU.

Although it resembles the asteroid belt between Mars and Jupiter in that it consists mainly of many small objects, unlike the its bodies are icy, rather than rocky. Gerard Kuiper was one of the who hypothesized this region in the 1950's to explain a particular class of comets, and he argued that the objects were remnants of the very primitive .

About 1000 Kuiper Belt Objects (KBOs) are known, and models suggest there could be many tens of thousands of them, with sizes ranging from meters to hundreds of kilometers. In addition, at least four dwarf planets orbit in this region: Pluto, Eris, Haumea and Makemake. Detecting KBOs is extremely difficult because they are so small and do not reflect much light.

The TAOS project (Taiwanese American Occultation Survey) is designed to detect new KBOs indirectly, by monitoring large fields of stars and searching for occultations -- when a KBO happens to pass between a star and earth, blocking the starlight. CfA astronomers Frederica Bianco, Matt Lehner, Matt Holman, Charles Alcock, and Pavlos Protopapas, together with a team of twenty-one colleagues, have just published the results of 3.75 years of TAOS observations, making this the first detailed study of occultation data.

Although they have not detected any KBOs so far, even the null result allows them to refine the current models. They also conclude that KBOs are probably structurally fragile, and that the orbital motions of played a key role in the formation of the Kuiper Belt as a whole.

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omatumr
3 / 5 (4) May 07, 2010
Will the study obtain information on the chemical and isotopic composition of objects beyond the orbit of Neptune?

That is the kind of information needed to confirm or deny the idea that the entire solar system formed out of heterogeneous debris ejected by the Sun 5 Gyr ago.

With kind regards,
Oliver K. Manuel
Shootist
5 / 5 (1) May 07, 2010
"That is the kind of information needed to confirm or deny the idea that the entire solar system formed out of heterogeneous debris ejected by the Sun 5 Gyr ago."

So, the pubescent sun belched out everything from hydrogen to uranium at sufficient velocity to not only spread the matter out to the Oort cloud (a light year or more) but also in the quantities necessary to condense all the material seen today, plus whatever escaped the solar system or fell back into the Sun?

Shootist
3 / 5 (2) May 07, 2010
We have a hundreds (thousands?) of telescopes in the world today and some in orbit. Any pictures of something like this happening?

I mean, there are photos of dust clouds and there are photos of stars forming in dust clouds and there are photos of stars whose dust clouds have been blown away but with debris disks and suggestions of stars with planets forming within the debris disks. But we don't see too many photos of stars, free of dust and debris, evolving into stars belching matter, evolving into stars with debris disks forming proto-planets, do we? I don't believe Eta Carina will be forming planets for its own use, though it does a great job a expelling gas and dust and the gas and dust it does expel will probably become part of a star or planet at some point an eon or two from now.
omatumr
1.5 / 5 (2) May 07, 2010
"That is the kind of information needed to confirm or deny the idea that the entire solar system formed out of heterogeneous debris ejected by the Sun 5 Gyr ago."

So, the pubescent sun belched out everything from hydrogen to uranium at sufficient velocity to not only spread the matter out to the Oort cloud (a light year or more) but also in the quantities necessary to condense all the material seen today, plus whatever escaped the solar system or fell back into the Sun?



Yes. See: "Xenon record of the early solar system", Nature 262, 28-32 (1976)

"Strange xenon, extinct super-heavy elements, and the solar neutrino puzzle", Science 195, 208-209 (1977)

"Isotopes of tellurium, xenon and krypton in the Allende meteorite retain record of nucleosynthesis", Nature 277, 615-620 (1979)

"The enigma of helium and anomalous xenon," Icarus 41, 312-315 (1980)

"Noble gas anomalies and synthesis of the chemical elements", Meteoritics 15, 117-138 (1980)
Shootist
5 / 5 (2) May 08, 2010
"Yes. See: "Xenon record of the early solar system", Nature 262, 28-32 (1976)" yada yada

We suggest that xenon isotopes in meteorites and in outer regions of the Sun contain debris from a supernova which exploded in the vicinity of the present Solar System, and we conclude that xenon in the outer planets is enriched in this supernova debris.

Nothing to do with Sol belching out material.
probes
2.5 / 5 (2) May 10, 2010
"Yes. See: "Xenon record of the early solar system", Nature 262, 28-32 (1976)" yada yada

Nothing to do with Sol belching out material.


This is true, you would need an artificial means of belching out this kind of material. A 200GW VASIMR engine for example.

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