高中(學測,指考)模擬考◆英文題庫下載題庫

The search for alien worlds orbiting other stars — exoplanets — has gone on a long time. Quite a few were thought to have been seen, but they were on the remote edge of what the technology could do and were later shown to be 26 positives. Then in 1995 came the big announcement: A planet had been found orbiting the star 51 Pegasi. The star is similar to the Sun, but the planet was a shock: it circled around the star in just 4.2 days, a 27 smaller and shorter orbit than had been thought possible. In 2009, Kepler, an observatory designed to stare at 150,000 stars simultaneously, was launched into space, carefully measuring their starlight. If a planet orbits the star, the planet will cross the face of its star, and then the starlight will darken periodically, revealing the 28 of the exoplanet. Kepler has found more than 1,000 confirmed exoplanets 29 thousands more candidates still awaiting confirmation. When will we find 30 Earth? The answer is: We may have already. And the statistics clearly show we’ll find plenty more in the next few years.