Nasa plans to “downscope” one of its flagship missions to keep it within cost estimates. This almost certainly means reducing its scientific capabilities.
The Wide Field Infrared Survey Telescope (WFirst) is designed to study essential astrophysical and cosmological questions. This ambitious mission began in 2016 when Nasa asked its scientists and engineers to come up with a mission that was as sensitive as the Hubble space telescope, but would have 100 times its field of view.
Initially, WFirst was projected to cost $1.6bn (£1.2bn), but that doubled as Nasa’s ambition grew. Earlier this year, an independent review panel found that the final cost was likely to be closer to $4bn.
This week Nasa decided to look at ways to return the costs to $3.2bn. These include using commercial rather than bespoke components and making cuts to the science instruments.
Although the cost-capping will affect the final science, it may be essential to ensure the mission goes ahead at all. In the past, Nasa has cancelled missions that significantly overran their budgets.
WFirst’s primary mission is to determine the behaviour of the mysterious dark energy that is accelerating the expansion of the universe, and to map the distribution of the equally mysterious dark matter across space. In addition, it will test a technology that will allow us to study the atmosphere of planets around other stars. This technology is called a coronagraph, and blocks the light from a star, allowing the fainter planets to be seen around it.
Nasa will review the new design in February 2018, and decide whether to proceed to the next stage of the mission.
