ESA reduces design of X-ray astronomy mission – SpaceNews

WASHINGTON – Amid rising costs, the European Space Agency is exploring ways to revamp the design of a large X-ray space telescope, an effort that could impact NASA’s own astrophysical programs.

ESA selected the Athena mission in 2014 as one of two flagship astrophysics missions, along with the Laser Interferometer Space Antenna (LISA). Athena – a name derived from Advanced Telescope for High-Energy Astrophysics – would be launched in the mid-2030s to study supermassive black holes, supernova explosions and other sources of X-rays with a large X-ray mirror.

At the time of selection, each ESA mission has an estimated cost of 1.05 billion euros ($1.07 billion), or about 1.17 billion euros today, said Paul McNamara, ESA’s astronomy and astrophysics coordinator, during a presentation on July 21 before NASA’s Astronomy and Astrophysics Committee. By 2019, however, the total price of Athena and LISA had grown to €2.5 billion.

As of May 2022, LISA has an estimated cost of €1.5 billion, but Athena had grown to €1.9 billion. This happened even when Athena was making good technical advances, he said, for example in the development of a new lightweight mirror technology.

Much of the recent surge, he said, came after member states that had planned to make their own contributions to the mission backed out. “Several member states concluded that they could not meet their commitments,” he said, “and asked ESA to take their responsibilities.” This increased ESA’s cost to Athena.

“These costs are not sustainable,” he said. “If we are to maintain the diverse content that is at the heart of our programming, we need to bring down the cost of our big missions.”

McNamara said there were no plans by ESA to abort Athena, but that the agency was instead considering a sort of “redesigned” mission at a cost of no more than 1.3 billion euros. “We need to recalibrate the Athena mission to significantly reduce its cost.”

This revised mission, currently referred to as NewAthena, would likely involve a reduction in her science. “At the moment it doesn’t seem feasible that we can move to March 1st. reach [billion euro] Goal, the cost-to-completion for the ESA, while maintaining the full scientific objectives of the mission,” he said.

These efforts include potential instrument configuration changes as well as the creation of a scientific “redefinition” team to revisit scientific goals. The aim will be to develop a revised concept, called a minimally disturbed mission, which will cost ESA no more than 1.3 billion euros, but will still provide the scientific output expected from a flagship-class mission.

What that means for Athena’s schedule is unclear. McNamara said ESA is preparing to “adopt” either Athena or LISA in November 2023 or move on to the next phase of development. The other will be adopted in 2024 or 2025.

Another uncertainty is the funding that will be available for Athena and LISA over the next few years, which ESA member states will decide at the next Ministerial Council meeting in November. “Right now we are anticipating potential resource levels going forward,” he said. “If we don’t get that, we don’t know what’s going to happen.”

A redesign of Athena could also affect NASA. The agency is contributing hardware for an instrument on Athena, as well as other resources such as testing and calibration facilities for its x-ray mirror. McNamara said ESA officials have been in touch with their NASA colleagues about plans for Athena.

He added ESA would not rule out increased collaboration with NASA to reduce ESA’s costs for the revised Athena mission. “No door is closed,” he said. “We’re looking at ways we can try to achieve the best possible mission within the programmatic constraints.”