Hubble Space Telescope and Significant Discoveries
Funding was approved in 1977 for a Large Space Telescope in 1977 and in 1983 it was renamed Hubble Space Telescope in honor of astronomer Edwin P. Hubble who discovered evidence of an expanding universe and the existence of other galaxies. Work was completed in 1985 and it was launched and deployed from the Space Shuttle Discovery in April of 1990, 350 miles above earth. Since its deployment, there have been five services, each service to perform corrective and preventive maintenance, add upgrades to the equipment, or both. In 2011, the Hubble space Telescope celebrated its millionth observation, the spectroscopic analysis of HAT-P-7b an exoplanet orbiting around the star HAT-P-7 (Spacetelescope.org, 2012).
Over the course of the 23 years since its deployment, the Hubble Space Telescope has made numerous significant discoveries. One of the most significant discoveries was the existence of dark energy. Two independent teams of astronomers using the Hubble, presented evidence and came to the same conclusion, the expansion of the universe was accelerating. This was significant because previously the theory was gravity would cause a slow deceleration and the original programs were written to calculate the deceleration based on supernovae data. What both teams found was the dimming of the supernovae was greater than predicted, meaning the distance was greater than predicted and the universe was expanding at an increasing rate rather than a decreasing rate (Villard, 2010). Based on Einstein’s theory of relativity, they theorized the acceleration is the result of the repulsive nature of dark energy. By studying cosmic microwave background, scientists have determined that dark energy makes up 73% of the energy density in the universe. Using type IA supernovae, the observations have determined that the transition from deceleration to acceleration occurred around 5 billion years ago and dark energy has been in existence as far back as 9 billion years ago but was not yet present in today’s quantity (Livio, 2010).
Another major discovery was the existence of dark matter. Based on observations of galaxies, galaxy clusters and cosmic microwave background, scientists determined that most of the universe’s mass is composed of dark matter. Dark matter does not emit light but can be detected by the way its gravity distorts the images of the background galaxies. Using large 3-D models of the distribution, scientists have determined dark matter clumping increases over time (Livio, 2010).
The Hubble Space Telescope has been key in not only confirming the universe’s expansion but also the further defining the rate of the expansion. Edwin Hubble in 1929 provided the first evidence of the expansion of the universe and its finite age with his Hubble constant. The constant says that the farther a galaxy is the faster the acceleration, therefore the universe is expanding. The ability of the Hubble Telescope...