Astrophysics Legacy: The Great Observatories

Ball's Astrophysics Legacy Lives On

By Andria Kelly

Humanity’s quest to unlock the secrets of the universe resulted in one of the most ambitious international scientific collaborations, NASA’s Great Observatories program. The undertaking aimed to construct four space-based observatories that would examine the cosmos in various wavelengths across the electromagnetic spectrum.

The Observatories debuted in 1990 with the launch of the now heralded Hubble Space Telescope, followed in later years by the Compton Gamma Ray Observatory, Chandra X-ray Observatory, and the Spitzer Space Telescope. Ball Aerospace played key roles in all four of the Great Observatories, and continues to leverage the innovative technologies developed for those missions in next-generation space telescopes. From the Kepler/K2 missions to NASA’s James Webb Space Telescope, Ball Aerospace is committed to advancing our knowledge of astrophysics and pioneering discoveries that go beyond.


The Hubble Space Telescope was the world’s first large, space-based telescope. Originally funded in the 1970s, anticipation was high when Hubble finally launched in 1990.  However, that quickly fizzled when scientists discovered Hubble’s primary mirror was improperly polished resulting in ‘fuzzy’ images. An innovative solution called COSTAR, built by Ball Aerospace, was installed on Hubble in 1993 and helped revealed the cosmos in crisp focus. From supporting the understanding of dark energy to using gravitational lensing to peer back towards the early history of the cosmos to studying the icy plumes on Europa, Hubble revolutionized humanity’s understanding of the universe, becoming an international sensation in the process.

Ball contributions played a significant role in Hubble’s success. Our personnel built two star trackers, five major leave-behind equipment subsystems, and more than eight custom tools to support astronauts during servicing missions. Ball’s science legacy was solidified by providing seven science instruments for the observatory: Goddard High Resolution Spectrograph (GHRS), Corrective Optics Space Telescope Axial Replacement (COSTAR), Advanced Camera for Surveys (ACS), Space Telescope Imaging Spectrograph (STIS), Near Infrared Camera and Multi-Object Spectrograph (NICMOS), Cosmic Origins Spectrograph (COS) and Wide Field Camera 3 (WFC3) , including five instruments currently operating aboard Hubble (NICMOS, STIS, ACS, WFC3, and COS). Hubble’s WFC-3, installed on Servicing Mission 4, was designed and built in partnership with NASA’s Goddard Space Flight Center and the Space Telescope Science Institute to greatly improve Hubble’s imaging capability by providing an expansive field of view, high sensitivity and wide spectral coverage. With WFC-3, Hubble’s coverage in the near ultraviolet wavelengths increased by a factor of 10 and coverage in the near infrared wavelengths increased by a factor of 30 over previous instruments. Lessons learned from Hubble have translated to its successor, NASA’s James Webb Space Telescope. On behalf of the prime contractor, Northrop Grumman, Ball designed and built the advanced optical components and cryogenic electronics system for this next Decadal mission.


A year after the launch of Hubble, the Compton Gamma Ray Observatory (CGRO) entered operation on a mission to explore high-energy phenomena in galaxies across the universe. CGRO’s unique combination of instruments detected a range of high-energy radiation called gamma rays. Ball contributed to the success of CRGO with its Oriented Scintillation Spectrometer Experiment (OSSE) and two fixed-head standard star trackers for this mission. The OSSE instrument completed the most comprehensive survey of the center of our Milky Way, discovering that radiation is focused toward the center of the galaxy. Compton returned valuable scientific date for nine years of operations before it was intentionally deorbited in 2000.


Not long after CGRO, NASA’s flagship mission for X-ray astronomy launched. The Chandra X-Ray Observatory returned highly-detailed X-ray images and data of the cosmos – from exploding stars to black holes - revealing the hidden secrets of our universe unseen by even the most powerful visible light telescopes like Hubble.

Ball built Chandra’s Aspect Camera, which points the observatory in the direction of its science targets, and the Science Instrument Module, which houses and controls the telescope’s two focal plane instruments. Chandra, which launched in 1999, continues to advance our understanding of the structure and evolution of our universe by probing the origins of heavy elements and understanding the local physics of black holes. Building on Chandra discoveries, X-ray innovations continue today with NASA’s latest X-ray astronomy mission, the Imaging X-ray Polarimetry Explorer (IXPE), which is slated to launch in 2020. IXPE will allow scientists to study the polarization of X-rays, offering clues the geometry of high-energy objects not previously visible to Chandra due to its lack of a polarimeter. As part of NASA’s low-cost astrophysics Explorers Program, Ball will provide the IXPE spacecraft and mission integration.


NASA’s fourth Great Observatory, the Spitzer Space Telescope, launched in 2003. Spitzer detects infrared energy, producing images from the heat radiating from celestial objects. Using infrared detectors, Spitzer captures celestial objects that are too dim, distant or cool to study with other astronomical techniques. Ball developed two of Spitzer’s three instruments, the Infrared Spectrograph and the Multiband Imaging Photometer, which were the most sensitive detectors ever flown on an infrared mission. Additionally, Ball was responsible for the cryogenic telescope assembly which acts as the “eye” of Spitzer.

Among Spitzer’s most notable discoveries are its analyses of the atmospheres of exoplanets – planets that orbit stars other than our own sun. Spitzer became the first telescope to directly capture light from exoplanets and has been very successful in looking beyond our solar system and peering at exoplanets, most recently discovering five of seven Earth-sized planets in the TRAPPIST-1 system.

Ball continues to innovate and advance technologies for tomorrow’s astrophysics missions. Our heritage dates back to 1956 and continues to go beyond as we design with science in mind. With a portfolio of NASA missions having expanded our understanding of the universe and continuing to do so today, Ball’s excitement for our continued partnership with NASA looks forward to the next steps.