The Hubble Space Telescope is one of the most famous telescopes and research tools launched into orbit around the Earth in 1990. The project from NASA took millions of dollars and years to build. The device is named after Edwin Hubble, an American astronomer who suggested that the universe is constantly expanding which implies that the universe had a beginning. Since its launch into space, the Hubble Telescope has made many important discoveries and sent back stunning images that have expanded our awareness of the universe. Its contribution to the field of astronomy has been incalculable and remains as NASA’s most successful mission, even though plans are in the works to eventually replace it.
The idea of a telescope orbiting the Earth has been around for a long time. Earlier space telescopes began to be developed in the 1960s and 1970s, and these inventions demonstrated the superiority of space-based observatories to those on the ground. In 1968, NASA began developing plans for a reflecting space telescope called the Large Space Telescope. As they began developing plans for the space shuttle program also, it was thought that a space telescope could be maintained and repaired through manned missions to extend the life of the device. Engineers and workers at NASA began on the design of the telescope and in setting forth what its scientific mission would be.
Getting the funding for such an enormous project was a major obstacle. At first, the U.S. Congress turned down any funding, but after significant lobbying and cuts in the scale of the project, Congress approved funding for it. In 1978, Congress approved $36 million dollars for the telescope. Several contractors and NASA centers worked on the telescope, including the Perkin-Elmer Corporation, Lockheed Martin, the Goddard Space Flight Center, the Marshall Space Flight Center, and the Space Telescope Science Institute all contributed to the development of the Hubble Telescope. After several delays, including the explosion of the Space Shuttle Challenger, the telescope was finally launched into orbit in 1990 aboard the Space Shuttle Discovery.
The Hubble Space Telescope is a type of telescope called a Cassegrain reflector. When light hits the primary mirror, it bounces off and it and then hits a secondary mirror. That secondary mirror focuses the light through a hole in the primary mirror’s center that leads to the scientific instruments of the telescope. The telescope orbits earth about once every ninety-seven minutes. The size of its primary mirror is 2.4 meters in diameter. The telescope also has two main computers and smaller systems to relay commands from NASA and to send data back to Earth via satellite.
The Hubble Telescope has a variety of scientific instruments that help it make observations and discoveries. The Fine Guidance Sensors keep the telescope pointed in the right direction and can be used to measure the precise distance of stars and their motions. The Near Infrared Camera and Multi-Object Spectrometer is a heat sensor that picks up infrared light and lets the telescope see into deep space. The Space Telescope Imaging Spectrograph hunts black holes, maps out galaxies, and gathers in visible, near-infrared, and ultraviolet light. The Advanced Camera for Surveys is designed to look for signs of the earliest activity of the universe by studying the evolution of galaxy clusters and the distribution of dark matter. The Cosmic Origins Spectrograph sees only in ultraviolet light and picks up different wavelengths from objects that help to study them. Finally, the Wide Field Camera 3 is used to study the formation of stars and dark matter.
Not long after its launch into orbit, NASA discovered a problem with the telescope’s primary mirror. Images that came back were blurry. In 1993, the Space Shuttle Endeavor was launched to make repairs. They installed what is known as the Corrective Optics Space Telescope Axial Replacement (COSTAR). This was to correct the mirror problem and replaced the Wide Field Planetary Camera with a newer version. The telescope has gone under many different repairs since then. In 1997, astronauts made another journey to give the telescope upgrades with the Near Infrared Camera and Multi-Object Spectrometer and the Space Telescope Imaging Spectrograph. In 1999, one of the Fine Guidance Sensors had to be replaced. Then, in 2002, the telescope received a serious upgrade with the Advanced Camera for Surveys, which doubled the Hubble’s field of view.
Another servicing mission was scheduled for 2006 but was called off after the Space Shuttle Columbia broke apart. The mission was instead launched in 2009 and included major repairs. Astronauts installed the Wide Field Camera 3 and the Cosmic Origins Spectrograph. They repaired the Advanced Camera for Surveys and the Space Telescope Imaging Spectrograph. They also replaced the telescope’s batteries, one of the Fine Guidance Sensors, and installed new insulating panels. They also removed COSTAR and replaced the Science Instrument Command and Data Handling unit which controls the instruments and the flow of data.
The Future Of Hubble
Over the years, the telescope has made many important discoveries and has helped expand our knowledge of the universe. It has played a key role in the discovery of dark matter and helped scientists determine a more precise age for the universe at about 13-14 billion years. The telescope has shown stars and galaxies in all their different stages of progression. It has discoveryed protoplanetary disks that serve in the formation of new planets and the bursts of gamma-rays when large stars collapse. These are just a few of the Hubble’s contribution to the study of space.
The Hubble Space Telescope is expected to be in service until at least 2020. However, plans are in the works for Hubble’s successor called the James Webb Space Telescope with a launch date of 2018. Although one day the Hubble Space Telescope will no longer be in use, it has given us a better understanding of our universe and the incredible world we live in.