It is laid-back fun to ponder what is out there in the Oort cloud. Usually the comets residing therein are pictured as a bunch of random dots, evenly distributed. That can't be the case as the T Tauri birth phase of the solar system 4.6 billion years ago was organized, not a random coalescence from the Mother Molecular birth cloud. To wit, the sun and planets are just a big saturn ring system wherein 99% of the mass goes into the central primary(of the original lenticular shape)but 99% of the cloud's original spin angular momentum goes into the orbiting planets and other minor debris(from the dust lane/accretion vortices by Bode's Law). Thus the comets, far from the sun, have the most SAM of the system, but as we look at galaxies and other assemblages in the universe, we see some kind of STRUCTURE, as in the primitive globular clusters orbiting the milky way. So, imagination time : just what is that overall STRUCTURE of trillions of comets in the Oort cloud out to 50,000 AU?
Out of This Solar System
By DENNIS OVERBYESTRANGERS among us?
People who still haven't gotten over the idea that Antarctica is littered with meteorites from Mars now have an even more fantastical example of cosmic intermingling to contemplate. Thousands or even millions of planetoids from another star are probably lurking in the outer regions of our solar system, courtesy of a near collision between our Sun and the other star with their nascent planetary systems more than 4 billion years ago.
In a Nature paper this week a pair of astronomers, Scott Kenyon of the Harvard-Smithsonian Center for Astrophysics and Brian [BENJAMIN!] Bromley of the University of Utah, invoked such a world-swapping encounter as the best way to explain a strange world known as Sedna. Named for the Inuit goddess of the seas, Sedna travels in elongated orbit far beyond Pluto and the rest of the known solar system, never venturing closer than about seven billion miles from the Sun. It is the coldest, most distant object known to orbit the sun ....
The interest in these aliens goes beyond Sedna itself, however, to what they might tell scientists about the formation of our own solar system and others ....