National Astronomy Week finds us safely at home, hoping not only to avoid one of the killer asteroids in the news lately but also to avert any other disastrous events that might be in the stars. (来源：专业英语学习网站 http://www.EnglishCN.com)

No, we're not in danger of losing our usually sunny disposition; we're just looking skyward for some tips on the varieties of aster out there.

We begin with the Greek aster that means "star;" this aster influenced dozens of words ranging from the heavenly asteroid (literally "starlike" in Greek, the English asteroid names any of the "small celestial bodies found especially between the orbits of Mars and Jupiter") to the earthbound, star-shaped aster flower to the all-too-human disastrous and disaster.

Why "all-too-human"? Because back in the Middle Ages, folks believed that stars had both positive and unpropitious—even baleful—aspects and could portend dis-aster.

Then there's the aster spelled A-S-T-R-E, whose meaning (and linguistic history) are very distant from the stars. This astre is synonymous with "hearth; home;"and, like the less earthbound asters, counts Latin and Greek words among its ancestors. But those ancestors have nothing to do with celestial bodies; the astre spelled R-E comes from a Medieval Latin term meaning "pavement of potsherds," or pottery fragments.