| A | B |
|---|
| blackhole | an object whose gravitiational pull is so strong that, within a certain distance of it, nothing can escape, not even light |
| bonds | forces tha thold compounds together; formed when atoms share electrons |
| chromosphere | the middle, gasious layer of the Sun's atmosphere |
| corona | the outer layer of the Sun's atmosphere |
| electron | a negatively charged in an atom |
| fusion reaction | a reaction in which the nuclei atoms combine to form more massive nuclei, with the simultaneous release of huge amounts of energy |
| nucleus | the center of an atom, consisting of protons and neutrons |
| neutron | a small, uncharged particle in the center of an atom |
| neutron star | a crushed remnant left over when a very massive star explodes; made almost entirely of neutrons |
| photosphere | the Sun's inner atmosphere |
| proton | a small, positively charged particle in the center of an atom |
| prominence | a huge arc of gas emitted from the Sun's surface during a solar storm |
| red giant | a very large, destended, and relatively coll star in the final stages of its life |
| solar constant | the amount of solar energy received per unit time by the upper layer of Earth's atmosphere |
| solar flare | a temparoary outburst of solar gases from a small area of the Sun's surface |
| sunspot | dark spots that appear on the Sun dduring times of increased solar activity |
| supernova | an explosion that marks the end of a very massive star's life |
| watt | a unit of power, indicating how fast energy is expended or received |
| white dwarf | the collapsed remnant of a relatively low-mass star |
