Credit: NASA/JPL-Caltech

This artist's concept shows NASA's Spitzer Space Telescope. Spitzer begins its "Beyond" mission phase on Oct. 1, 2016. The spacecraft is depicted in the orientation it assumes to establish communications with ground stations.

Celebrating the spacecraft’s ability to push the boundaries of space science and technology, NASA’s Spitzer Space Telescope team has dubbed the next phase of its journey “Beyond.”

“Spitzer is operating well beyond the limits that were set for it at the beginning of the mission,” said Michael Werner, the project scientist for Spitzer at NASA’s Jet Propulsion Laboratory in Pasadena. “We never envisioned operating 13 years after launch, and scientists are making discoveries in areas of science we never imagined exploring with the spacecraft.”

NASA recently granted the spacecraft a two-and-a-half-year mission extension. This Beyond phase of the Spitzer mission will explore a wide range of topics in astronomy and cosmology, as well as planetary bodies in and out of our solar system.

Because of Spitzer’s orbit and age, the Beyond phase presents a variety of new engineering challenges.

Spitzer trails Earth in its journey around the sun, but because the spacecraft travels slower than Earth, the distance between Spitzer and Earth has widened over time. As Spitzer gets farther away, its antenna must be pointed at higher angles toward the sun to communicate with Earth, which means that parts of the spacecraft will experience more and more heat.

At the same time, Spitzer’s solar panels point away from the sun and will receive less sunlight, so the batteries will be under greater stress. To enable this riskier mode of operations, the mission team will have to override some autonomous safety systems.

“Balancing these concerns on a heat-sensitive spacecraft will be a delicate dance, but engineers are hard at work preparing for the new challenges in the Beyond phase,” said Mark Effertz, the Spitzer spacecraft chief engineer at Lockheed Martin Space Systems Company, Littleton, Colorado, which built the spacecraft.

 Spitzer, which launched on Aug. 25, 2003, has consistently adapted to new scientific and engineering challenges during its mission, and the team expects it will continue to do so during the “Beyond” phase, which begins Oct. 1. The selected research proposals for the Beyond phase, also known as Cycle 13, include a variety of objects that Spitzer wasn’t originally planned to address — such as galaxies in the early universe, the black hole at the center of the Milky Way and exoplanets.

“We never even considered using Spitzer for studying exoplanets when it launched,” said Sean Carey of NASA’s Spitzer Science Center at Caltech in Pasadena. “It would have seemed ludicrous back then, but now it’s an important part of what Spitzer does.”

Spitzer’s Beyond mission phase will last until the commissioning phase of NASA’s James Webb Space Telescope, currently planned to launch in October 2018. Spitzer is set to identify targets that Webb can later observe more intensely.

“We are very excited to continue Spitzer in its Beyond phase. We fully expect new, exciting discoveries to be made over the next two-and-a-half years,” said Suzanne Dodd, project manager for Spitzer, based at JPL.