NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, was successfully launched from Kwajalein Atoll in the central Pacific Ocean June 13.
The mission will study everything from massive black holes to our own sun.
The observatory was perched atop an Orbital Sciences Corp Pegasus XL rocket, that was strapped to the bottom of, the L-1011 Stargazer aircraft, also operated by Orbital. Stargazer dropped the rocket at 9 a.m., PDT, half an hour past the first scheduled time. The delay was needed to check out a suspicious reading, which the launch team decided would not interfere with the mission.
The launch and NuSTAR deployment gave “nominal readings throughout,” according to Tim Dunn, assistant launch control officer.
Pegasus was released from Stargazer at about 39,000 feet, and the first stage rocket motor ignited five seconds later. It burned for 70 seconds and then dropped away. The second-stage motor burned for about a minute-and-a-half, during which pyrotechnic devices fired to release the nose cone fairing that encapsulates the observatory. NuSTAR will be exposed to space for the first time.
At 13 minutes after the initial release from Stargazer, NuSTAR separated from the Pegasus rocket’s third stage. At this point, NuSTAR is in its final orbit – a low-Earth equatorial orbit at an altitude of approximately 340 miles and an inclination of six degrees.
NuSTAR is the first space telescope to create focused images of cosmic X-rays with the highest energies. The telescope will have more than 10 times the resolution and more than 100 times the sensitivity of its predecessors while operating at this energy range, at which X-rays re called gamma rays. NuSTAR weighs 772 lb.
The mission will work with other telescopes in space now, including NASA’s Chandra X-ray Observatory, which observes lower-energy X-rays. Together, they will provide a more complete picture of the most energetic and exotic objects in space, such as black holes, dead stars and jets traveling near the speed of light.
NuSTAR will study black holes that are big and small, far and near, answering questions about the formation and physics behind these wonders of the cosmos. The observatory will also investigate how exploding stars forge the elements that make up planets and people, and it will even study our own sun’s atmosphere.
The observatory is able to focus the high-energy X-ray light into sharp images because of a complex, innovative telescope design. High-energy light is difficult to focus because it only reflects off mirrors when hitting at nearly parallel angles. NuSTAR solves this problem with nested shells of mirrors. It has the most nested shells ever used in a space telescope: 133 in each of two optic units. The mirrors were molded from ultra-thin glass similar to that found in laptop screens and glazed with even thinner layers of reflective coating.
The telescope also consists of state-of-the-art detectors and a lengthy 33-foot mast, which connects the detectors to the nested mirrors, providing the long distance required to focus the X-rays. This mast is folded up into a canister small enough to fit atop the Pegasus launch vehicle. It will unfurl in about seven days after launch. About 23 days later, science operations will begin
“We will see the hottest, densest and most energetic objects with a fundamentally new, high-energy X-ray telescope that can obtain much deeper and crisper images than before,” said Fiona Harrison, the NuSTAR principal investigator at the California Institute of Technology in Pasadena, Calif., who first conceived of the mission 20 years ago.
“NuSTAR uses several innovations for its unprecedented imaging capability and was made possible by many partners,” said Yunjin Kim, the project manager for the mission at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “We’re all really excited to see the fruition of our work begin its mission in space.”
“NuSTAR truly demonstrates the value that NASA’s research and development programs provide in advancing the nation’s science agenda,” said Paul Hertz, NASA’s Astrophysics Division director. “Taking just over four years from receiving the project go-ahead to launch, this low-cost Explorer mission will use new mirror and detector technology that was developed in NASA’s basic research program and tested in NASA’s scientific ballooning program. The result of these modest investments is a small space telescope that will provide world-class science in an important but relatively unexplored band of the electromagnetic spectrum.”
NuSTAR is a Small Explorer mission led by Caltech and managed by JPL for NASA’s Science Mission Directorate in Washington. The spacecraft was built by Orbital Sciences Corp. Its instrument was built by a consortium including Caltech; JPL; University of California at Berkeley); Columbia University in New York; NASA’s Goddard Space Flight Center; the Danish Technical University in Denmark; Lawrence Livermore National Laboratory; and ATK Aerospace Systems in Goleta, Calif. NuSTAR will be operated by UC Berkeley, with the Italian Space Agency providing its equatorial ground station located at Malindi, Kenya. The mission’s outreach program is based at Sonoma State University in Rohnert Park, Calif. NASA’s Explorer Program is managed by Goddard. JPL is managed by Caltech for NASA.