The Hubble Telescope Essay Research Paper The — страница 2
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million years, the Milky Way will have captured Sagittarius. Astrophysicist John Bahcall of the Institute for the Advanced Study in Princeton, New Jersey, says Of all the secrets that the Hubble has unlocked, its images of galaxies that formed when the universe was in its infancy would be at the top of my list of its achievements. HST speaks eloquently to how galaxies got started and got together, something we argue about endlessly. The Hubble Deep Field is an image taken over the course of 10 days in December 1995. It shows how the Hubble Space Telescope is also the Hubble Time Machine . Light falling on the space telescope today left its source at some time in the past because images form when light hits a telescope and light travels at 186,000 miles per second. Light from the sun takes 8.3 minutes to reach the earth, so when we look at the sun, we are seeing it as it was 8.3 minutes ago. Because light from an object billions of miles away began its journey years ago, astronomical distances can be measured in light-years , which is the distance light travels in a year. So the image we see is the object as it appeared in the past. The images in the Hubble Deep Field appear as they were roughly 11.7 billion to 10.4 billion years ago. Only an astronomer living 10 billion years in the future will know what these objects look like today. If the big bang theory is right, then the data from the HST can be used to calculate the age of the universe. The space telescope s nominal mission , as NASA calls it, runs until 2005. In 2002, space walkers will install a new spectrograph. Astronomers hope that the Hubble can operate until the year 2010. As Robert Williams, director of the Space Telescope Science Institute, paraphrases, The HST has shown us not only that the universe is stranger than we supposed, but that it is stranger than we can suppose.