The answer is: choose a star near the ecliptic plane of the Solar System and watch it carefully. About once per thousand years, a KBO will pass in front of it. This will make it dim out for a little less than a second, on average. This is a good way to look for small KBOs, not the rare big ones like 2004 DW. Seem like a tough job? It gets easier if you can watch many thousands of stars at a time, then you might see a few events per year. This is exactly what will soon be attempted by my friends at the Taiwanese-American Occultation Survey (TAOS). Should be starting up later this year.
There are two general possibilities here, and we don't know which is more important. First, the orbits aren't really stable---the entire solar system is chaotic, but the instabilities can take billions of years to manifest themselves. The KBO orbits can slowly evolve to become Neptune-crossing, then once this happens Neptune can catapult the object on its way to the inner solar system.
Alternatively, KBOs get redirected into less stable orbits when the encounter Pluto or each other. This would also be a rare event.
The three new discoveries are about 42 AU from the Sun, in orbits that are about the same distance but less inclined (tipped) to the rest of the Solar System than Quaoar. They are not "plutinos".
Press releases are always skimpy on the real information; if you want the gory details, read the
scientific paper. There will be some articles in Science News, maybe other places, at an intermediate level.
Some answers to posted questions from the one who did the research & wrote the press release:
How do we know these things came from our Solar System and not another one? The response about the directions of orbits is good; all the Kuiper Belt Objects (KBOs) and all the known planets orbit in the same direction around the Sun. Wouldn't happen if things were falling in randomly, so almost certainly reflects the rotation of the disk of gas & dust from which our solar system formed. Also, why would it be any easier to make a chunk of ice/rock around another star and have it accidentally caught be our star thousands of light years away, then to just make it around our star? There are grains of dust moving through our Solar System that appear to come from interstellar space, but no big chunks.
Another posts said that comets are the true fossils; in fact short-period comets (including the ones targeted by the spacecraft) are believed to be escapees from the Kuiper Belt. Comets are being evaporated by the Sun (that's why they look so big, they have clouds around them) and so they'll evaporate to nothing but rubble in 10,000 years or so. Not very long by astronomy standards. So there must be unborn comets in "cold storage" somewhere far from the Sun.
The New Horizons mission to Pluto & Kuiper Belt object(s) is alive & kicking. Our discovery means it will be a little harder to find a Kuiper Belt target for them to hit, but it should still be possible. There probably is a dust cloud associated with the Kuiper Belt (debris from collisions), which is doughnut-shaped, but this cloud is not very dense and won't be a threat to the spacecraft. Space is very empty, even in a "crowded" neighborhood like the inner Solar System.
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The answer is: choose a star near the ecliptic plane of the Solar System and watch it carefully. About once per thousand years, a KBO will pass in front of it. This will make it dim out for a little less than a second, on average. This is a good way to look for small KBOs, not the rare big ones like 2004 DW. Seem like a tough job? It gets easier if you can watch many thousands of stars at a time, then you might see a few events per year. This is exactly what will soon be attempted by my friends at the Taiwanese-American Occultation Survey (TAOS). Should be starting up later this year.
There are two general possibilities here, and we don't know which is more important. First, the orbits aren't really stable---the entire solar system is chaotic, but the instabilities can take billions of years to manifest themselves. The KBO orbits can slowly evolve to become Neptune-crossing, then once this happens Neptune can catapult the object on its way to the inner solar system.
Alternatively, KBOs get redirected into less stable orbits when the encounter Pluto or each other. This would also be a rare event.
The three new discoveries are about 42 AU from the Sun, in orbits that are about the same distance but less inclined (tipped) to the rest of the Solar System than Quaoar. They are not "plutinos".
Press releases are always skimpy on the real information; if you want the gory details, read the scientific paper. There will be some articles in Science News, maybe other places, at an intermediate level.
Some answers to posted questions from the one who did the research & wrote the press release:
How do we know these things came from our Solar System and not another one? The response about the directions of orbits is good; all the Kuiper Belt Objects (KBOs) and all the known planets orbit in the same direction around the Sun. Wouldn't happen if things were falling in randomly, so almost certainly reflects the rotation of the disk of gas & dust from which our solar system formed. Also, why would it be any easier to make a chunk of ice/rock around another star and have it accidentally caught be our star thousands of light years away, then to just make it around our star? There are grains of dust moving through our Solar System that appear to come from interstellar space, but no big chunks.
Another posts said that comets are the true fossils; in fact short-period comets (including the ones targeted by the spacecraft) are believed to be escapees from the Kuiper Belt. Comets are being evaporated by the Sun (that's why they look so big, they have clouds around them) and so they'll evaporate to nothing but rubble in 10,000 years or so. Not very long by astronomy standards. So there must be unborn comets in "cold storage" somewhere far from the Sun.
The New Horizons mission to Pluto & Kuiper Belt object(s) is alive & kicking. Our discovery means it will be a little harder to find a Kuiper Belt target for them to hit, but it should still be possible. There probably is a dust cloud associated with the Kuiper Belt (debris from collisions), which is doughnut-shaped, but this cloud is not very dense and won't be a threat to the spacecraft. Space is very empty, even in a "crowded" neighborhood like the inner Solar System.