Astronomy terms starting with L

7 terms

1. Lambda, Λ The cosmological constant, which measures the energy density of the vacuum.
2. Large Scale Structure Galaxies, galaxy clusters, and galaxy superclusters.
3. Last Scattering Surface The farthest back in the history of the universe that photons could travel freely.
4. Light A pane of glass; a window, or a compartment of a window.
5. Light Year The distance light travels in a year: {Distance equals rate times time: 300,000,000 meters per second, times roughly 30 million seconds equals roughly} 9.
6. Local Group A small cluster of more than 30 galaxies "near" to our galaxy, including the Andromeda galaxy and the Magellanic Clouds.
7. Luminosity The total energy released by an object emitting light, (in our case, this will be a star) per unit time (usually per second).