Service mission successful so far
Last servicing of Hubble under way
Galaxies from the early universe. The birthplaces of planets. Dark matter. Dark energy. Since its launch in 1990, the Hubble Space Telescope has brought these mysteries into focus, its powerful gaze scanning the universe for the details planet-bound telescopes find impossible to detect.
Far above the Earth's surface, Hubble floats clear of the planet's light-distorting atmosphere, beaming back images that have transfixed humanity and changed the scientific world.
Hubble's triumphs continue to accumulate thanks to a unique design that allows astronauts to repair and upgrade the telescope while it remains in orbit. Repairs keep the telescope functioning smoothly, while upgrades to the instruments bring a slew of new discoveries and science.
The current mission, Servicing Mission 4 (SM4), is the final trip to the Hubble Telescope. Over the course of five spacewalks, astronauts are installing two new instruments, repair two inactive ones, and perform the component replacements that will keep the telescope functioning at least into 2014. The effort-intensive, rigorously researched, exhaustively tested mission also involves diverse groups of people on the ground throughout the country.
The Servicing Mission started on May 11, with the successful launch of the space shuttle Atlantis from the Kennedy Space Center. Today STIS' electronics card was successfully installed and the new cover mounted. Also during the fourth spacewalk the focus was to continue repairs and make improvements that will extend the Hubble Space Telescope’s life into the next decade.
The mission's planning is years in the making, and its success will be the product of months of intensive preparation and the work of hundreds of people at NASA and in academia and industry.
When the astronauts have finished all of their tasks, they will use the robotic arm again to release the telescope, and Goddard will issue the commands to bring the telescope back into operation. But before Hubble's science mission can resume, the telescope will undergo a several-month-long testing and calibrating period. The first new images from the telescope will be released in mid-2009.
Many of the telescope's components, especially the instruments, were designed to be easily removed and replaced during servicing missions. This mission's primary scientific priority is the installation of Hubble's new instruments, Wide Field Camera 3 (WFC3) and the Cosmic Origins Spectrograph (COS).
Wide Field Camera 3 will be the power behind studies of dark energy and dark matter, the formation of individual stars and the discovery of extremely remote galaxies previously beyond Hubble's vision. WFC3 sees three different kinds of light: near-ultraviolet, visible and near-infrared, though not simultaneously. The camera's range is much greater than that of the instruments currently aboard.
Galaxy evolution, the formation of planets, the rise of the elements needed for life, and the "cosmic web" of gas between galaxies will be some of the areas of study for the Cosmic Origins Spectrograph (COS). A spectrograph is an instrument that breaks light into its component colors, revealing information about the object emitting the light. COS sees exclusively in ultraviolet light and will improve Hubble's ultraviolet sensitivity at least 10 times, and up to 70 times when observing extremely faint objects.
But before it can try out its new equipment, the telescope needs maintenance. The computer that sends commands to Hubble's science instruments malfunctioned 17 days before the planned October 14, 2008 launch date. The mission was postponed to give engineers on the ground time to test the flight spare unit and train the spacewalking astronauts.
Restored and updated, Hubble will continue on its journey around the Earth, its new components merging seamlessly with the old, a rejuvenated telescope ready for years of groundbreaking revelations from the universe.