VOA慢速英语:冥王星诞生之初也许是一片“热土”

solar – adj. related to the sun

journal – n. a magazine that reports on things of special interest to a group of people

author – n. writer

dwarf – adj. related to or involving something that is much smaller than the usual size

impact – v. formal to hit (something) with great force

sufficient – adj. somewhat formal having or providing as much as is needed

core – n. the central or most important part of something

ingredient – n. a part or piece of something