Why would anyone want to build a large telescope for use in space? The cost is prohibitive (about $2.4 billion) and, if repairs are needed, it almost takes an act of Congress to fix one. Critics have claimed that a better ground-based telescope could be built for a fraction of the cost.
Such were some of the arguments against the construction of the Hubble Space Telescope (HST) before its NASA launch in 1990. Despite early problems with its main mirror, the HST has proven to be one of the greatest scientific instruments of all time, providing stunning images of the heavens and remarkable insight into the origin of the universe.1 As the HST nears the end of its mission, a new space telescope promises even more striking (and faith-affirming) views of the cosmos.
NASA is in the design stage for Hubble’s replacement,the James Webb Space Telescope (JWST), due to be launched in 2013. It will be larger (~256 inches in diameter versus 94 inches for Hubble) and will work at longer wavelengths (into the infrared) to provide deeper, earlier views back in time to when the stars and galaxies formed at the very beginning of the universe.
One of the biggest changes, however, is that the JWST will not orbit the Earth directly like the Hubble, but will orbit the Sun in a position beyond the orbit of the Earth called L2—short for the second Lagrangian point. Back in the late 1700s the French mathematician Joseph-Louis Lagrange attempted to mathematically describe the motion of three massive bodies bound together by gravity (it’s called the “three-body problem” in physics). Lagrange discovered several locations where a small body (in this case the JWST) could orbit a large body (the Sun) in the presence of a smaller, but still large, second body (the Earth). One of those locations, the L2, moves along with the Earth, about 1.5 million kilometers farther out from the Sun. Being in the shadow of the Earth, the JWST will be able to function continuously with little light disturbance from the Sun. Also, its greater distance will significantly reduce the heat energy coming from the Earth, which is critically important for infrared observation.
These benefits provide distinct advantages over ground-based telescopes, which are hampered by limitations. The obstacles include occasional bad weather, light pollution due to the Moon and city lights, the presence of the Sun for half the day, and turbulence in the Earth’s atmosphere yielding poorer resolution. Therefore, the high costs of implementation, upgrades, and repairs for a new space telescope are more than justified with the promise of spectacular results.
Reasons To Believe scholars look forward with excitement to the JWST launch. We anticipate a continuing parade of new discoveries that will affirm the accuracy of RTB’s creation model and the reliability of the Bible as the word of God.
- For more information see NASA’s Web site for the Hubble Space Telescope at http://hubble.nasa.gov/index.php.
- For more information see NASA’s Web site for the James Webb Space Telescope at http://www.jwst.nasa.gov/index.html.