Astro Definitions Flashcards
Define Planet
A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf.
Define Sun
the star around which the earth moves and that provides light and heat for the earth:
Define Dwarf Planet
a celestial body that -orbits the sun, has enough mass to assume a nearly round shape, has not cleared the neighborhood around its orbit and is not a moon.
Define Big Bang Theory
The Big Bang Theory explains how the universe began with an infinitely hot and dense single point
Define Star
A star is a body that possesses a light that causes it to reflect the light independently.
Define Red Shift
the wavelength of the light is stretched, so the light is seen as ‘shifted’ towards the red part of the spectrum. This happens when something is moving away
Define Cosmic Microwave Background Radiation
leftover radiation from the Big Bang or the time when the universe began.
Define Singularity
In the big bang theory all energy was originally concentrated at one point in the universe
Define Positrons
a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron
Define Nuclear Reaction
A nuclear reaction is a process in which two nuclei, or a nucleus and an external subatomic particle, collide to produce one or more new nuclides.
Define Fusion
combining lighter atomic nuclei to form a heavier nucleus
Define Nebula
a cloud of gas and dust in outer space
Define Protostar
A protostar is the earliest stage of a star’s life cycle
Define Main Sequence Stars
The midlife of a star. Main sequence stars fuse hydrogen atoms to form helium atoms in their cores
Define Red Giant
The core contracts –
increases in temperature – and the outer shell
expands.
