tailieunhanh - Nature Vol 457

Four hundred years ago, the Universe changed. Or, at least, our perception of it did, thanks to Galileo Galilei’s scrutiny of the night sky with a telescope. Within a couple of years, his observations of the Moon, phases of Venus and satellites of Jupiter shattered the old Ptolemaic model of our Solar System. To the church’s dismay, Earth assumed its rightful place as one of several planets orbiting the Sun (see page 28). Marking Galileo’s anniversary, the International Year of Astronomy seeks to remind us of the humbling nature of gazing at the heavens. Through programmes offering cheap telescopes for the masses, teaching materials and global heritage projects, astronomers are. | nature nature nature Vol 457 Issue no. 7225 1 January 2009 Starry messages The first scientific observations with telescopes displaced Earth from the centre of the Universe. Modern technology continues to humble us but should not distance us from the cosmos itself. Four hundred years ago the Universe changed. Or at least our perception of it did thanks to Galileo Galilei s scrutiny of the night sky with a telescope. Within a couple of years his observations of the Moon phases of Venus and satellites of Jupiter shattered the old Ptolemaic model of our Solar System. To the church s dismay Earth assumed its rightful place as one of several planets orbiting the Sun see page 28 . Marking Galileos anniversary the International Year of Astronomy seeks to remind us of the humbling nature of gazing at the heavens. Through programmes offering cheap telescopes for the masses teaching materials and global heritage projects astronomers are inviting us all to look up and ponder our place in the Universe. That this prospect is novel speaks to the distance that has come between people and their environment. Urban light pollution means that one-fifth of the world s population can no longer see the Milky Way with the naked eye. Many city kids even if they did peer through the orange smog above their heads would probably see only a handful of stars. Astronomers are calling for the dark places on Earth to be preserved as national parks so that we do not lose completely our window on the Universe see page 27 . Astronomers in communicating their work have a natural ally in beautiful images. The Hubble Space Telescope has a place in the public s heart for this reason although it has accomplished outstanding science too see page 41 . But professional astronomers themselves are not immune to distancing. The technological advances that have given so much insight into astrophysics have made astronomy one of the most computer-intensive of the natural sciences. Surveys churn out