AST 2002 Lecture Notes - Lecture 22: Solar Wind, Pioneer Plaque, Liquid Hydrogen
Document Summary
Seti looks for signals for intelligent life. Why have we not heard from other life or been visited by them. We are first galaxy just now getting nice. The(cid:455) are out there, (cid:271)ut we (cid:272)a(cid:374)"t hear the(cid:373) Great filter is something that causes civilization to just stop. A pair of gold-anodized aluminum plaques which were placed on board the spacecraft, featuring a pictorial message, in case the spacecraft is intercepted by extraterrestrial life. More massive cores, which can capture and hold hydrogen and helium. The conditions as you get farther down into jupiter it gets hotter and pressure increases. Almost entirely h, he but not all gaseous. Group together jupiter and saturn, uranus and neptune. Jupiter inside gradual transition from gas to liquid hydrogen & helium: even further, liquid hydrogen and helium turn into metals, originally end up at original planetesimal rock, metal, ices, pressure at the center is very high.
