Interpreting the results
HWO will examine the atmospheres of at least 25 potentially habitable worlds, searching for biosignatures that could indicate the presence of life.
The detection of biosignatures requires context, so that we can avoid being fooled by non-life processes. Key Earth biosignatures sought by HWO will include oxygen, ozone, and methane, though others are also under consideration. Scientists will have to apply what they know about the planets and moons in our own Solar System to interpret the conditions on the exoplanets HWO observes.
“That type of ‘ground truth’ is very important when we’re looking for life,” Quick said. “In order to understand how prospects for life on Earth-like exoplanets may be affected by geological processes at their surfaces, we must first understand how geological processes on Earth and potentially habitable bodies in our Solar System, such as Europa, Mars, and Titan, have affected their suitability to harbor life over time.”
Conceptual work on HWO is proceeding through two teams: START (Science, Technology, Architecture Review Team), which is working on the telescope’s science objectives, and TAG (Technical Assessment Group), which is working on technical requirements.
In official NASA parlance, the project is in its pre-formulation phase. A project office at NASA Headquarters is expected to be established this year, which will move HWO into a “pre-phase A” status.
It will take years to mature the technologies needed to build HWO and get the telescope ready for launch. But one day in the not-so-distant future, the observatory could train its eyes on a star system not unlike our own, and pick out the first signs of life on another world.